Establishing a Bloodline
By Amy Greenwood Burford
One of the most frequently asked questions at the ADBA office this last year has been, “How do I become a breeder and establish my own bloodline? The answer could encompass a whole book, so I will begin by breaking down the question into a few of the fundamental parts and begin putting together the answer that will help guide those new fanciers that have this interest. The motivation to become a breeder can be twofold. Number one: the individual wants to preserve and maintain the quality of the dogs that he has noted in a dog or a number of dogs that he has come in contact with, or number two: the individual wants to improve or incorporate a new characteristic into a family of dogs that he is involved with.
Breeding a litter of pups is not the same as becoming a breeder and developing a bloodline. Many fine dogs have been produced by the former, but to continue to develop and refine the finest characteristics of the breed into a family of dogs that breed true for these characteristics is the definition of a ‘bloodline’ and the ultimate goal of a ‘breeder’ . We have within our breed bloodlines that are known for producing great dogs as well as bloodlines that are known for producing mediocre dogs with certain problems, i.e. conformation faults, health issues, temperament faults etc. The newcomer that is interested in developing a’ bloodline’ must understand that it is more that having your name carried as a part of the registered name of the dog. It is the development of a family of dogs that breed true for breed characteristics that you deem as essential and desirable, and that have been selectively bred into your family of dogs.
Becoming a breeder and developing a ‘bloodline’ demands that you establish a breeding plan. Number one is to identify those breed characteristics that you want to see reproduced in the dogs that you will produce. Identifying your individual list of characteristics that you want to develop in your bloodline requires that you are familiar with the breed character and are knowledgeable about the breed standards that have been established by the experts within the breed. You will also need knowledge about structural soundness and genetic health issues within the breed. Number two is to develop your eye for a dog, to be able to evaluate one dog from another in terms of those traits that you are breeding for.
This is a tall order for someone new in the breed, and it is the reason why many longtime fanciers spend years and years in the breed, before starting their careers as breeders. Newcomers can expand their knowledge by becoming involved with local breeders and fanciers in their local area. Attendance at shows and weight pulling events, and talking to judges and exhibitors about the dogs can also enhance ones understanding. A study of the literature available about the breed and about dogs, genetics and breeding in general is also essential. The breeding of fine dogs is an art, with a strong scientific basis. What a breeder seeks to produce, the ideal that he formulates, is self expression – the fulfillment of the creative urge. That lies the joy of breeding dogs. The emphasis a breeder places upon soundness, a great head or the dogs correct front-end or backend declares his own nature. The breeder who would achieve a consistent color or size at the cost of breed type or honest structure is a different kind of person from one who prefers a correctly made dog.
All quality bloodlines have been established by incorporating quality brood stock from someone else’s bloodline. It is not often that you can incorporate your pet quality bitch or dog into your breeding program and produce consistent quality pups. When I first got into the dogs and wanted advice on breeding, the advice that I received most often was to buy the best bitch that I could afford from a top kennel and then select one of the top quality studs being offered open to public stud to breed her to. Top producing dogs are most often inbred or line bred individuals from an outstanding bloodline. Inbreeding and line breeding produces a prepotent dog whose genetic material is homozygous. Homozygous is a term that indicates that the gene pairs are the same. Since only one gene is inherited from each parent, if the parents are related, as in inbreeding and line breeding, the chance of doubling up the gene pair is greater than in the case of breeding unrelated dogs, or outcross breeding. The term prepotent means a dog that can produce offspring with his same characteristics. The reason is that a dog that is homozygous for a certain trait will pass this trait 100% of the time to their offspring. A dog produced from an outcrossed breeding that is heterozygous (the gene pairs being different) for a certain trait, even though they themselves have the trait will pass the trait on to their offspring only 50% of the time. A breeding dog needs to be selected based on the dogs bloodline, the method of breeding that produced the dog (inbreeding or line breeding) and the individual attritibutes that the individual dog will bring to the breeding program.
Before making the commitment to become a breeder and establish your own bloodline, an honest appraisal of your resources is in order. First do you have the money and time to invest in this endeavor? A large kennel facility is usually not necessary if you get two or three quality bitches to start out with. A small residential kennel where you can spend the time necessary to care for the brood matrons and to socialize and evaluate the pups produced is all that is needed to get started. More important than space and money is the commitment to the pups that you will be producing. For breeders to know if their breeding program is working, ongoing evaluation of the pups is essential. Most of us, do not have unlimited space, so placing pups in good homes when they will receive adequate care and nutrition, training and evaluation is going to be essential. As a breeder, I only breed a litter when I need a dog myself to show or to breed, or if I have interested people that I feel will do a good job with the puppy. I like to place puppies within a 100 mile area of where I live so I can get feedback about the quality, temperament and performance of the dogs as they grow, and get a chance to see them at the local shows.
Darwin’s theory of natural selection states that when a natural breeding in the wild takes place,’ NATURE’ places demands on the individuals produced and the strong survive to reproduce and the weak die. In this scenario, as a dog breeder you are ‘NATURE’. Your role is to give an honest appraisal of the dogs that you produce, and breed only the strong. The weak, or dogs with characteristics that you do not want in your breeding program, should be spayed and neutered and placed in good pet homes. This is where many, many breeders fail. Over time, they become kennel blind and emotional about their pups, and keep inferior dogs as breeding stock for one reason or another. Many times a breeding partnership works best, a husband and wife, or kennel partners as they can keep one another on track about the quality of the offspring that is being produced. What dogs should be kept and which needs to be sold, or placed in pet homes.
At this time, I think I have presented readers and would be breeders with a lot to think about. In a follow-up article in the next issue of the Gazette, I will discuss the evaluation of a pedigree, the selection of a stud dog and the utilization of different types of breeding, i.e. inbreeding, line breeding and outcross breeding and the strengths and limitation of each.
http://www.adbadog.com/p_pdetails.asp?fspid=105
Saturday, May 4, 2013
Establishin a Bloodline Part II.
Establishing a Bloodline: Selection of brood stock and breeding styles
By Amy Greenwood Burford
Establishing a Bloodline
(part two) Selection of brood stock and breeding styles.
In the last issue of the Gazette, I covered some of the important issues that need to be considered when one makes the commitment to become a breeder of quality APBTs. This second article, I hope will give novice breeders more information on the next steps to take in moving the breeding program forward in establishing your 'bloodline'.
Once a breeder has developed a breeding plan, an evaluation of the brood stock that you are going to be using is the next step. First and foremost, the individual stud dog or brood bitch must possess the outstanding traits that the breeder is looking for in the offspring. The mating of animals with similar characteristics tends to produce offspring that resemble themselves. This is known as like-to-like, type-to-type or positive assortive mating. It is obvious that breeders should avoid mating animals with the same faults, as this type of mating will also tend to produce offspring with those faults set within the family of dogs.
An analysis of the dog's pedigree is the second but equally important step that must be considered in the selection of brood stock. For novices, a dog's pedigree is usually meaningless. For the experienced fancier, the pedigree is a profile of genetic potential, containing an unlimited amount of information. Knowledge about the individual dogs in the pedigree can be obtained firsthand from the dog's breeder. Pictures and information on the dogs can frequently be obtained from the numerous breed magazines and breeders websites. Conformation and weight pulling titles on the individual dogs can also be used in compiling your data base of information on the dog's pedigree. After a number of years into a persons breeding program, the breeder will have first hand knowledge of the dogs making up the pedigree of the breeding stock. Also a data base of information concerning the littermates as well as offspring from repeat breedings should be available to the breeder. This first hand information will always be the most reliable if the breeder remains objective in his evaluation of his pups.
Pedigree analysis will also reveal the style of breeding that produced the stud dog or brood bitch. Why would this be important? Certain styles of breeding, namely inbreeding and linebreeding tend to fix and preserve desirable traits by increasing homozygosity of the genes. This means that the gene pairs are the same. Since the gene pairs are the same, the genes for their quality will be passed to the dog's offspring 100% of the time. Outcross breeding increases heterozygosity of the genes. This is where the gene pairs are not the same. Dogs that are the product of an outcross breeding will pass the genes for their quality traits to their offspring only 50% of the time because most of the time their genetic makeup is heterozygous. The value of a stud dog or brood bitch lies in the dog's ability to consistently and predictably pass specific traits to their offspring. This is spoken of as being prepotent. This is what we are looking for in our brood stock. The ideal brood bitch or stud dog would be a dog that has the traits that the breeder was looking to produce and would be the product of an inbreeding or linebreeding.
STYLES OF BREEDING:
Inbreeding: Inbreeding is usually defined as the mating of closely related individuals. Some references include half brother to half sister mating as well as brother to sister, father to daughter, mother to son, grandsire to granddaughter and granddam to grandson breedings as examples of inbreeding. Other references define 'closely related' as brother to sister or closer. Another way I like to think of inbreeding is mating the individual dog to a dog that is IN the dog's pedigree. Regardless of how you define it, the goal of inbreeding is to fix and preserve the traits that the breeder is looking for by increasing homozygosity in the dog's genetic pool. You can calculate the inbreeding coefficient, or the probability of the genes being homozygous by looking at the number of times that a certain dog is present in the dog's pedigree. In every generation, each parent transmits only one half of his or her genes, and each subsequent generation again reduces the genes from an individual in half: in other words, 50 percent in the first generation, 25 percent in the second generation and 12.5 percent in the third. When the same ancestor appears in the pedigree of both the sire and dam, it increases the probability that the same genes will be present in the offspring and that they will be homozygous.
From breed to breed and bloodline to bloodline the popularity of inbreeding can vary. The more sound the bloodline (void of structural faults and health problems) the more successful inbreeding will be. This is because, inbreeding leads to random fixation of traits, increases homozygosity of the genes and for some genes, can cause inbreeding depression. Some genes causing detrimental health effects are only expressed in the homozygous state. They remain hidden (recessive) until as a consequence of inbreeding the genes are made homozygous. You then see the trait expressed in the offspring. One example of this is the gene causing juvenile cataracts in the Boston Terrier. When mating two dogs that are heterozygous or carriers for the gene together the probability is 25% of the bad genes becoming homozygous and causing blindness in the affected offspring. In the heterozygous or carrier state, the dogs are unaffected and will have good vision. A breeder could be totally unaware of a dog being a carrier for this gene unless a thorough pedigree analysis was done for this trait, or when the dog produces an affected pup.
Within a breed, it is not uncommon to see a breeder use half brother to half sister breedings with great success for about four generations, and then run into a brick wall where they find that a bad trait that was occasionally seen is now being expressed 100% of the time in the offspring. This is because of the fixing of the trait within the family because of the resulting homozygosity of the genes.
Knowledgeable dog breeders can use inbreeding as an effective tool to achieve specific goals and to enhance desired traits, if they are carefully alert for developing problems. Many novice breeders feel that inbreeding is the only way to develop their own strain or bloodline. In the wrong hands inbreeding can be dangerous. If the novice starts with a fair or poor quality dog then begins to inbreed to one of the close relatives they are likely to run into trouble. If one plans to use inbreeding in their breeding program, the breeder must have high quality, sound brood stock and a knowledge of what was behind them.
Before deciding to use inbreeding in your breeding plan there are some questions that a breeder might consider: How inbred is the brood bitch or stud dog itself? Are there any recessive hereditary disorders known in your stud dog or brood bitch's bloodline? What breed faults might you be concentrating or passing on to the resulting offspring? What are the positive effects that you are hoping to achieve by inbreeding?
Careful inbreeding is often of great value to a breeder. It is most successful when the highest quality dogs are used as brood stock, the breeder has a thorough knowledge of the dog's pedigree and intends to fix within the bloodline specific desirable traits.
Linebreeding: This term is often used to denote breeding among related individuals or dogs from the same family or bloodline. Examples would be mating between first or second cousins, uncle to niece, aunt to nephew, and in some references half brother to half sister is also listed as an example of linebreeding. Linebreeding is the breeding style that is a compromise between inbreeding and outcross breeding. Breeders use line breeding to preserve the traits of a family of dogs while at the same time retaining the variability in the gene pool. Variability is good as it counteracts the potential detrimental effects of doubling up on bad genes that is sometimes seen as a consequence of inbreeding. Line breeding is a slower and less direct way to fix desirable traits in a bloodline, but does offer more options and fewer risks than inbreeding. Diligent selection of quality brood stock from bloodlines known for their soundness and breed type is also very important when a breeder is choosing to do linebreeding.
Outcross breeding: The definition of outcross breeding is the mating of purebred dogs within the same breed that are relatively unrelated. The style of breeding increases heterozygosity and creates new genetic combinations by bringing together genes from totally unrelated individuals. There are two primary reasons that a knowledgeable breeder will choose to make an outcross breeding. The first is to introduce into their family of dogs a trait that is absent or lacking, and secondly to dilute undesirable traits that are caused by homozygous recessive genes. Outcross breeding is essential when a breeding program begins to show signs of inbreeding depression such as loss of vigor, disease resistance and infertility. Many times breeders will have two basic inbred or linebred families of dogs or bloodlines within their kennel and will do outcross breeding between these two lines. The result will be dogs that are 'better' than the two original lines. Breeders speak of this as a 'nick'. Geneticists speak of this as 'hybrid vigor'. No matter what you want to call it, this type of breeding will many times produce animals that are better than each of the original lines. Many times these dogs produced from outcross breeding have gone on to become athletic top performance animals. We have seen many famous 'nicks' within our breed, none more notable than the Tudor/ Colby breeding of Howard Heinzl and the Boudreaux/ Carver breeding of the Honeybunch line. Both of these bloodlines have produced many outstanding individuals as well as becoming the foundation of many other quality bloodlines today.
Many times using these talented performance dogs that are the product of outcross breeding as brood stock will result in a disappointment for the breeder, as the dogs will tend to produce the norm of their respective bloodlines. Many an old time breeder has been heard to say, "don't breed to the top performance dog of the day, breed to his parents". On the downside, many breeders frown on the use of outcross breeding as it does introduce unknown and sometimes undesirable traits into the bloodline. Also with an outcross mating of dogs that are already the product of outcross breeding, there is little predictability and uniformity in the traits that one will see in the offspring. Within a litter of pups, you can see good pups, poor quality pups and everything in between. Uniformity and predictability in the quality of the pups produced is the goal and the hallmark of a good breeder.
One of the most effective ways I have seen an outcross breeding used by breeders is to select to breed to an unrelated dog with a sound pedigree that possesses an outstanding quality that is absent or lacking in the breeders bloodline. From the resulting offspring an individual is selected for the trait that the breeder is looking to introduce into his line. That dog is then bred back into the original bloodline (linebred or inbred) fixing the new desirable trait into the original bloodline. One breeder explained the breeding strategy of bringing a quarter outcross into his line to be used as a 'catalyst' for the line. A 'catalyst' in the sense of bringing together all the goodness and quality of his bloodline with an added kick of hybrid vigor.
Grading Up: Breeding the females on hand to a male of better quality is known as grading up. The best females in each generation are then kept and again bred to a top sire from an outstanding bloodline. This is one of the tried and true ways to improve the quality of a cattle herd and other livestock. This is also true of many dog breeders. Many breeders have started with a very average bitch from a good bloodline and have invested their money wisely in breeding to an outstanding champion stud. As their experience increases they have refined their selection process, retaining the best in each generation. Careful selection of the top studs have in many cases produced a foundation of brood stock that have gone on to develop into a quality bloodline. There have also been many examples of breeders going astray and developing bloodlines that have consistently produced average or inferior dogs because of loss of focus into the selection of quality brood stock or chasing after the latest fad in breeding style or individual dogs.
Selection of breeding stock, the pedigree analysis and the styles of breeding are all tools that a breeder can use to develop his bloodline of dogs. High standards, diligent pedigree research and honest evaluation of the dogs the breeder is producing are also essential to guide the breeder to a successful program. What might work for one breeder may or may not work for another. This is why breeding dogs is considered as much as an 'art' as it is a 'science'. In the next issue of the Gazette, I will present a look into some breeding programs of some top breeders as examples to demonstrate the principals that have been outlined in my first two articles.
http://www.adbadog.com/p_pdetails.asp?fspid=107
By Amy Greenwood Burford
Establishing a Bloodline
(part two) Selection of brood stock and breeding styles.
In the last issue of the Gazette, I covered some of the important issues that need to be considered when one makes the commitment to become a breeder of quality APBTs. This second article, I hope will give novice breeders more information on the next steps to take in moving the breeding program forward in establishing your 'bloodline'.
Once a breeder has developed a breeding plan, an evaluation of the brood stock that you are going to be using is the next step. First and foremost, the individual stud dog or brood bitch must possess the outstanding traits that the breeder is looking for in the offspring. The mating of animals with similar characteristics tends to produce offspring that resemble themselves. This is known as like-to-like, type-to-type or positive assortive mating. It is obvious that breeders should avoid mating animals with the same faults, as this type of mating will also tend to produce offspring with those faults set within the family of dogs.
An analysis of the dog's pedigree is the second but equally important step that must be considered in the selection of brood stock. For novices, a dog's pedigree is usually meaningless. For the experienced fancier, the pedigree is a profile of genetic potential, containing an unlimited amount of information. Knowledge about the individual dogs in the pedigree can be obtained firsthand from the dog's breeder. Pictures and information on the dogs can frequently be obtained from the numerous breed magazines and breeders websites. Conformation and weight pulling titles on the individual dogs can also be used in compiling your data base of information on the dog's pedigree. After a number of years into a persons breeding program, the breeder will have first hand knowledge of the dogs making up the pedigree of the breeding stock. Also a data base of information concerning the littermates as well as offspring from repeat breedings should be available to the breeder. This first hand information will always be the most reliable if the breeder remains objective in his evaluation of his pups.
Pedigree analysis will also reveal the style of breeding that produced the stud dog or brood bitch. Why would this be important? Certain styles of breeding, namely inbreeding and linebreeding tend to fix and preserve desirable traits by increasing homozygosity of the genes. This means that the gene pairs are the same. Since the gene pairs are the same, the genes for their quality will be passed to the dog's offspring 100% of the time. Outcross breeding increases heterozygosity of the genes. This is where the gene pairs are not the same. Dogs that are the product of an outcross breeding will pass the genes for their quality traits to their offspring only 50% of the time because most of the time their genetic makeup is heterozygous. The value of a stud dog or brood bitch lies in the dog's ability to consistently and predictably pass specific traits to their offspring. This is spoken of as being prepotent. This is what we are looking for in our brood stock. The ideal brood bitch or stud dog would be a dog that has the traits that the breeder was looking to produce and would be the product of an inbreeding or linebreeding.
STYLES OF BREEDING:
Inbreeding: Inbreeding is usually defined as the mating of closely related individuals. Some references include half brother to half sister mating as well as brother to sister, father to daughter, mother to son, grandsire to granddaughter and granddam to grandson breedings as examples of inbreeding. Other references define 'closely related' as brother to sister or closer. Another way I like to think of inbreeding is mating the individual dog to a dog that is IN the dog's pedigree. Regardless of how you define it, the goal of inbreeding is to fix and preserve the traits that the breeder is looking for by increasing homozygosity in the dog's genetic pool. You can calculate the inbreeding coefficient, or the probability of the genes being homozygous by looking at the number of times that a certain dog is present in the dog's pedigree. In every generation, each parent transmits only one half of his or her genes, and each subsequent generation again reduces the genes from an individual in half: in other words, 50 percent in the first generation, 25 percent in the second generation and 12.5 percent in the third. When the same ancestor appears in the pedigree of both the sire and dam, it increases the probability that the same genes will be present in the offspring and that they will be homozygous.
From breed to breed and bloodline to bloodline the popularity of inbreeding can vary. The more sound the bloodline (void of structural faults and health problems) the more successful inbreeding will be. This is because, inbreeding leads to random fixation of traits, increases homozygosity of the genes and for some genes, can cause inbreeding depression. Some genes causing detrimental health effects are only expressed in the homozygous state. They remain hidden (recessive) until as a consequence of inbreeding the genes are made homozygous. You then see the trait expressed in the offspring. One example of this is the gene causing juvenile cataracts in the Boston Terrier. When mating two dogs that are heterozygous or carriers for the gene together the probability is 25% of the bad genes becoming homozygous and causing blindness in the affected offspring. In the heterozygous or carrier state, the dogs are unaffected and will have good vision. A breeder could be totally unaware of a dog being a carrier for this gene unless a thorough pedigree analysis was done for this trait, or when the dog produces an affected pup.
Within a breed, it is not uncommon to see a breeder use half brother to half sister breedings with great success for about four generations, and then run into a brick wall where they find that a bad trait that was occasionally seen is now being expressed 100% of the time in the offspring. This is because of the fixing of the trait within the family because of the resulting homozygosity of the genes.
Knowledgeable dog breeders can use inbreeding as an effective tool to achieve specific goals and to enhance desired traits, if they are carefully alert for developing problems. Many novice breeders feel that inbreeding is the only way to develop their own strain or bloodline. In the wrong hands inbreeding can be dangerous. If the novice starts with a fair or poor quality dog then begins to inbreed to one of the close relatives they are likely to run into trouble. If one plans to use inbreeding in their breeding program, the breeder must have high quality, sound brood stock and a knowledge of what was behind them.
Before deciding to use inbreeding in your breeding plan there are some questions that a breeder might consider: How inbred is the brood bitch or stud dog itself? Are there any recessive hereditary disorders known in your stud dog or brood bitch's bloodline? What breed faults might you be concentrating or passing on to the resulting offspring? What are the positive effects that you are hoping to achieve by inbreeding?
Careful inbreeding is often of great value to a breeder. It is most successful when the highest quality dogs are used as brood stock, the breeder has a thorough knowledge of the dog's pedigree and intends to fix within the bloodline specific desirable traits.
Linebreeding: This term is often used to denote breeding among related individuals or dogs from the same family or bloodline. Examples would be mating between first or second cousins, uncle to niece, aunt to nephew, and in some references half brother to half sister is also listed as an example of linebreeding. Linebreeding is the breeding style that is a compromise between inbreeding and outcross breeding. Breeders use line breeding to preserve the traits of a family of dogs while at the same time retaining the variability in the gene pool. Variability is good as it counteracts the potential detrimental effects of doubling up on bad genes that is sometimes seen as a consequence of inbreeding. Line breeding is a slower and less direct way to fix desirable traits in a bloodline, but does offer more options and fewer risks than inbreeding. Diligent selection of quality brood stock from bloodlines known for their soundness and breed type is also very important when a breeder is choosing to do linebreeding.
Outcross breeding: The definition of outcross breeding is the mating of purebred dogs within the same breed that are relatively unrelated. The style of breeding increases heterozygosity and creates new genetic combinations by bringing together genes from totally unrelated individuals. There are two primary reasons that a knowledgeable breeder will choose to make an outcross breeding. The first is to introduce into their family of dogs a trait that is absent or lacking, and secondly to dilute undesirable traits that are caused by homozygous recessive genes. Outcross breeding is essential when a breeding program begins to show signs of inbreeding depression such as loss of vigor, disease resistance and infertility. Many times breeders will have two basic inbred or linebred families of dogs or bloodlines within their kennel and will do outcross breeding between these two lines. The result will be dogs that are 'better' than the two original lines. Breeders speak of this as a 'nick'. Geneticists speak of this as 'hybrid vigor'. No matter what you want to call it, this type of breeding will many times produce animals that are better than each of the original lines. Many times these dogs produced from outcross breeding have gone on to become athletic top performance animals. We have seen many famous 'nicks' within our breed, none more notable than the Tudor/ Colby breeding of Howard Heinzl and the Boudreaux/ Carver breeding of the Honeybunch line. Both of these bloodlines have produced many outstanding individuals as well as becoming the foundation of many other quality bloodlines today.
Many times using these talented performance dogs that are the product of outcross breeding as brood stock will result in a disappointment for the breeder, as the dogs will tend to produce the norm of their respective bloodlines. Many an old time breeder has been heard to say, "don't breed to the top performance dog of the day, breed to his parents". On the downside, many breeders frown on the use of outcross breeding as it does introduce unknown and sometimes undesirable traits into the bloodline. Also with an outcross mating of dogs that are already the product of outcross breeding, there is little predictability and uniformity in the traits that one will see in the offspring. Within a litter of pups, you can see good pups, poor quality pups and everything in between. Uniformity and predictability in the quality of the pups produced is the goal and the hallmark of a good breeder.
One of the most effective ways I have seen an outcross breeding used by breeders is to select to breed to an unrelated dog with a sound pedigree that possesses an outstanding quality that is absent or lacking in the breeders bloodline. From the resulting offspring an individual is selected for the trait that the breeder is looking to introduce into his line. That dog is then bred back into the original bloodline (linebred or inbred) fixing the new desirable trait into the original bloodline. One breeder explained the breeding strategy of bringing a quarter outcross into his line to be used as a 'catalyst' for the line. A 'catalyst' in the sense of bringing together all the goodness and quality of his bloodline with an added kick of hybrid vigor.
Grading Up: Breeding the females on hand to a male of better quality is known as grading up. The best females in each generation are then kept and again bred to a top sire from an outstanding bloodline. This is one of the tried and true ways to improve the quality of a cattle herd and other livestock. This is also true of many dog breeders. Many breeders have started with a very average bitch from a good bloodline and have invested their money wisely in breeding to an outstanding champion stud. As their experience increases they have refined their selection process, retaining the best in each generation. Careful selection of the top studs have in many cases produced a foundation of brood stock that have gone on to develop into a quality bloodline. There have also been many examples of breeders going astray and developing bloodlines that have consistently produced average or inferior dogs because of loss of focus into the selection of quality brood stock or chasing after the latest fad in breeding style or individual dogs.
Selection of breeding stock, the pedigree analysis and the styles of breeding are all tools that a breeder can use to develop his bloodline of dogs. High standards, diligent pedigree research and honest evaluation of the dogs the breeder is producing are also essential to guide the breeder to a successful program. What might work for one breeder may or may not work for another. This is why breeding dogs is considered as much as an 'art' as it is a 'science'. In the next issue of the Gazette, I will present a look into some breeding programs of some top breeders as examples to demonstrate the principals that have been outlined in my first two articles.
http://www.adbadog.com/p_pdetails.asp?fspid=107
Methods of Artifical Insemination & Their Usage
by Robert Van Hutchinson, DVM
Historically, if multiple attempts for a natural breeding did not succeed, a last ditch effort of depositing semen in the vaginal tract was performed. Occasionally puppies resulted, often a smaller than average litter, but more often than not, the bitch did not conceive, and the artificial insemination was blamed.
The ability to accurately time the ovulatory pattern of the bitch has shown the canine breeder that artificial insemination can be as successful as natural breeding. Semen evaluation can be performed pre-breeding to assure the owner that the semen appears viable.
The routine use of "compromised life" semen such as fresh-chilled or frozen semen required artificial insemination to become common place. The need for frozen canine semen to be placed into the uterus rather than the vaginal tract necessitated the development of new methods for breeding the bitch.
The bitch is unique when her estrous cycle is compared to that of other domestic species. The bitch ovulates her eggs into a progesterone environment rather than estrogen as occurs in other domestic species. Estrogen measurement (vaginal smears, breeding guns), therefore, cannot be used for ovulation timing in the canine. When a natural breeding is performed, the semen is deposited in the vagina and "pumped" into the uterus by hormonal release stimulated by the tie. The lumen of the cervix in the average size bitch in estrous, is approximately the diameter of the insert in a Bic pen. The "Z"shape of the cervical lumen also prevents the insertion of even a small size catheter into the uterus.
The ova that the bitch ovulates are not ready for fertilization until a final meiotic division takes place. The time for ova maturation is a minimum of 48 hours post ovulation. This factor is especially important when short lived semen such as frozen semen is being used. Frozen semen is thought to only live 12-24 hours in the uterus after thawing and insemination. Frozen semen is only minimally effective when deposited vaginally (less than 20% conception success in one study), and not into the uterus. Is it any wonder that the initial impressions of canine frozen semen were less than spectacular!?
Currently, however, the use of frozen semen and fresh-cooled semen is every bit as effective as natural breeding. One of the main reasons for the conception success is the understanding by both breeders and veterinarians that the artificial insemination methods must be properly timed, properly performed and that certain bitches and types of semen require different methods of insemination.
If both breeding participants are present, fertile and ovulation timed ready, a natural breeding is performed. If for some reason a natural cannot be achieved, then a vaginal artificial insemination is used to breed the bitch. The technique requires specific procedures be performed.
The male's semen is collected. This is achieved by manual stimulation. The collector needs to obtain the second fraction of the ejaculate (the milky, sperm rich portion) stopping the collection when the third fraction starts (watery in appearance) which consists of prostatic fluid.
The bitch should have her rear end elevated for the artificial insemination procedure. This positioning facilitates the semen's deposition and flow to the cervical opening, a necessary for the semen being in position to be "pumped" into the uterus. The inseminator should digitally stoke the roof of the vaginal tract (also called "feathering") for 1-2 minutes after insemination. This technique simulates the tie of a natural breeding. The bitch's rear should be elevated for 2-3 minutes post-insemination.
The necessity to bypass the cervix and place the semen into the uterine lumen is beneficial in improving the conception rates in numerous situations. These include the use of frozen semen, fresh cooled semen, poor semen quality and in situations where examination of the bitch's uterus is desired.
Two methods are used to achieve the intrauterine deposition of semen, the transcervical insemination and the surgical insemination. These techniques each have their own usage guidelines and one does not replace the other as has been mistakenly represented to dog breeders.
The transcervical insemination (TCI) is performed with the bitch in a standing position. No sedation nor anesthesia is required. A fiber optic cystourethoscope is used vaginally to visualize the opening to the cervix. A flexible catheter is maneuvered through the cervix into the uterus. It is important that the breeder realize that the veterinarian is not visualizing the inside of the uterus and this technique does not allow for evaluation of the uterus.
The TCI procedure is visualized on a television monitor and does allow for examination of the vaginal tract, however. The semen is gently pushed through the catheter from a syringe. The veterinarian can visualize that the semen flows easily into the uterus and does not flow back into the vaginal tract.
The transcervical insemination does not replace the surgical insemination as it does not allow for uterine evaluation, but is a significant improvement over the vaginal method of artificial insemination. The TCI is recommended for any type semen, especially frozen and fresh-cooled and can significantly increase conception when poor quality semen and lowered sperm numbers are used. The TCI technique should be used in bitches less than 5 years of age where there is not a reason to suspect uterine changes or uterine disease.
The surgical method of artificial insemination is especially useful when breeding "middle age" and older bitches (5years of age and older). The unique biology of the bitch exposes the uterine lining to the inflammatory effects of progesterone for 60+ days, whether she is pregnant or not, accounts for the progressive changes in the uterus from a normal endometrium to cystic endometrial hyperplasia. These changes eventually render the bitch prone to such diseases as mucometrium and pyometritis. Pyometritis is a hormonal disease with a secondary infection, not a primary infection of the uterus.
The changes to the uterine lining can affect conception in many ways. The endometrial cysts can affect the semen's ability to reach the fallopian tubes where conception occurs (regardless of the method of insemination). The cystic changes can also prevent implantation of the fertilized ova, which occurs 17-18 days after ovulation and can inhibit placental development and growth.
A surgical insemination is a minor surgical procedure that allows the surgeon to inject the semen directly into the uterus. As the surgeon has the uterus in his hands, cysts, uterine wall thickness and muscular texture can be evaluated. There is no more accurate method to perform this vital examine. In many bitches, that have a surgical insemination, corrections can be made to the uterus that allow for conception to occur. A bitch's greatest chance of conception is by having a surgical semen implant.
A pre-surgical blood value examination is performed on the bitch, which is also beneficial to assure good prebreeding health. The surgical procedure is performed under sterile conditions.
The bitch is given a short acting intravenous injection of Propofol. An endotracheal tube is placed and the bitch is connected to a gas anesthetic, Sevothane. Even though the total surgical time is usually no longer than 10-15 minutes the bitch is connected to surgical monitoring.
A 2-3 inch incision is made on the abdomen through the skin and underlying muscle. The uterus is isolated and evaluated. The semen, whether fresh collected, fresh chilled or frozen, is inseminated though a small hypodermic needle into the uterus. The veterinary surgeon can see and feel the uterus fill as the semen is deposited. There is no incision in the uterus proper. The incision is sutured and in most cases the bitch is sent home within an hour post-surgically.
A bitch that has had surgical inseminations is not more prone to needing a ceasarean section nor having whelping difficulties. Having a surgical insemination does not decrease the number of times a bitch can be bred. A surgical insemination should be considered anytime there is a reason to evaluate the uterus (bitches 5 years and older) or where the semen being used can benefit from intrauterine implantation.
Our whole goal when breeding a bitch is to maximize the chances for conception. The manner and method that the semen is placed into the bitch should be evaluated critically as to whether a natural breeding, vaginal insemination, transcervical insemination or surgical intrauterine implant, gives the bitch the greatest chance of conception. Ultimately this will allow us to have the litter of which we have planned and dreamed.
http://classic.akc.org/vetoutreach/headlinenews_13.cfm
Historically, if multiple attempts for a natural breeding did not succeed, a last ditch effort of depositing semen in the vaginal tract was performed. Occasionally puppies resulted, often a smaller than average litter, but more often than not, the bitch did not conceive, and the artificial insemination was blamed.
The ability to accurately time the ovulatory pattern of the bitch has shown the canine breeder that artificial insemination can be as successful as natural breeding. Semen evaluation can be performed pre-breeding to assure the owner that the semen appears viable.
The routine use of "compromised life" semen such as fresh-chilled or frozen semen required artificial insemination to become common place. The need for frozen canine semen to be placed into the uterus rather than the vaginal tract necessitated the development of new methods for breeding the bitch.
The bitch is unique when her estrous cycle is compared to that of other domestic species. The bitch ovulates her eggs into a progesterone environment rather than estrogen as occurs in other domestic species. Estrogen measurement (vaginal smears, breeding guns), therefore, cannot be used for ovulation timing in the canine. When a natural breeding is performed, the semen is deposited in the vagina and "pumped" into the uterus by hormonal release stimulated by the tie. The lumen of the cervix in the average size bitch in estrous, is approximately the diameter of the insert in a Bic pen. The "Z"shape of the cervical lumen also prevents the insertion of even a small size catheter into the uterus.
The ova that the bitch ovulates are not ready for fertilization until a final meiotic division takes place. The time for ova maturation is a minimum of 48 hours post ovulation. This factor is especially important when short lived semen such as frozen semen is being used. Frozen semen is thought to only live 12-24 hours in the uterus after thawing and insemination. Frozen semen is only minimally effective when deposited vaginally (less than 20% conception success in one study), and not into the uterus. Is it any wonder that the initial impressions of canine frozen semen were less than spectacular!?
Currently, however, the use of frozen semen and fresh-cooled semen is every bit as effective as natural breeding. One of the main reasons for the conception success is the understanding by both breeders and veterinarians that the artificial insemination methods must be properly timed, properly performed and that certain bitches and types of semen require different methods of insemination.
If both breeding participants are present, fertile and ovulation timed ready, a natural breeding is performed. If for some reason a natural cannot be achieved, then a vaginal artificial insemination is used to breed the bitch. The technique requires specific procedures be performed.
The male's semen is collected. This is achieved by manual stimulation. The collector needs to obtain the second fraction of the ejaculate (the milky, sperm rich portion) stopping the collection when the third fraction starts (watery in appearance) which consists of prostatic fluid.
The bitch should have her rear end elevated for the artificial insemination procedure. This positioning facilitates the semen's deposition and flow to the cervical opening, a necessary for the semen being in position to be "pumped" into the uterus. The inseminator should digitally stoke the roof of the vaginal tract (also called "feathering") for 1-2 minutes after insemination. This technique simulates the tie of a natural breeding. The bitch's rear should be elevated for 2-3 minutes post-insemination.
The necessity to bypass the cervix and place the semen into the uterine lumen is beneficial in improving the conception rates in numerous situations. These include the use of frozen semen, fresh cooled semen, poor semen quality and in situations where examination of the bitch's uterus is desired.
Two methods are used to achieve the intrauterine deposition of semen, the transcervical insemination and the surgical insemination. These techniques each have their own usage guidelines and one does not replace the other as has been mistakenly represented to dog breeders.
The transcervical insemination (TCI) is performed with the bitch in a standing position. No sedation nor anesthesia is required. A fiber optic cystourethoscope is used vaginally to visualize the opening to the cervix. A flexible catheter is maneuvered through the cervix into the uterus. It is important that the breeder realize that the veterinarian is not visualizing the inside of the uterus and this technique does not allow for evaluation of the uterus.
The TCI procedure is visualized on a television monitor and does allow for examination of the vaginal tract, however. The semen is gently pushed through the catheter from a syringe. The veterinarian can visualize that the semen flows easily into the uterus and does not flow back into the vaginal tract.
The transcervical insemination does not replace the surgical insemination as it does not allow for uterine evaluation, but is a significant improvement over the vaginal method of artificial insemination. The TCI is recommended for any type semen, especially frozen and fresh-cooled and can significantly increase conception when poor quality semen and lowered sperm numbers are used. The TCI technique should be used in bitches less than 5 years of age where there is not a reason to suspect uterine changes or uterine disease.
The surgical method of artificial insemination is especially useful when breeding "middle age" and older bitches (5years of age and older). The unique biology of the bitch exposes the uterine lining to the inflammatory effects of progesterone for 60+ days, whether she is pregnant or not, accounts for the progressive changes in the uterus from a normal endometrium to cystic endometrial hyperplasia. These changes eventually render the bitch prone to such diseases as mucometrium and pyometritis. Pyometritis is a hormonal disease with a secondary infection, not a primary infection of the uterus.
The changes to the uterine lining can affect conception in many ways. The endometrial cysts can affect the semen's ability to reach the fallopian tubes where conception occurs (regardless of the method of insemination). The cystic changes can also prevent implantation of the fertilized ova, which occurs 17-18 days after ovulation and can inhibit placental development and growth.
A surgical insemination is a minor surgical procedure that allows the surgeon to inject the semen directly into the uterus. As the surgeon has the uterus in his hands, cysts, uterine wall thickness and muscular texture can be evaluated. There is no more accurate method to perform this vital examine. In many bitches, that have a surgical insemination, corrections can be made to the uterus that allow for conception to occur. A bitch's greatest chance of conception is by having a surgical semen implant.
A pre-surgical blood value examination is performed on the bitch, which is also beneficial to assure good prebreeding health. The surgical procedure is performed under sterile conditions.
The bitch is given a short acting intravenous injection of Propofol. An endotracheal tube is placed and the bitch is connected to a gas anesthetic, Sevothane. Even though the total surgical time is usually no longer than 10-15 minutes the bitch is connected to surgical monitoring.
A 2-3 inch incision is made on the abdomen through the skin and underlying muscle. The uterus is isolated and evaluated. The semen, whether fresh collected, fresh chilled or frozen, is inseminated though a small hypodermic needle into the uterus. The veterinary surgeon can see and feel the uterus fill as the semen is deposited. There is no incision in the uterus proper. The incision is sutured and in most cases the bitch is sent home within an hour post-surgically.
A bitch that has had surgical inseminations is not more prone to needing a ceasarean section nor having whelping difficulties. Having a surgical insemination does not decrease the number of times a bitch can be bred. A surgical insemination should be considered anytime there is a reason to evaluate the uterus (bitches 5 years and older) or where the semen being used can benefit from intrauterine implantation.
Our whole goal when breeding a bitch is to maximize the chances for conception. The manner and method that the semen is placed into the bitch should be evaluated critically as to whether a natural breeding, vaginal insemination, transcervical insemination or surgical intrauterine implant, gives the bitch the greatest chance of conception. Ultimately this will allow us to have the litter of which we have planned and dreamed.
http://classic.akc.org/vetoutreach/headlinenews_13.cfm
Thursday, May 2, 2013
Canie Reproduction............
Tuesday, January 08, 2002
DrHutch: Good evening!
PCFFasDog: Good evening and thank you all for being here! We are very excited to welcome Dr. Robert Van Hutchison to our first Canine Reproduction Seminar.
This free seminar is sponsored by Veterinary Perinatal Specialties, Inc., home of the WhelpWise service. Please visit their website at http://www.whelpwise.com, and show your support for their sponsorship of this event!
Many of you already know Dr. Hutchison or have seen him speak in person. He is one of the leading canine reproduction experts in the world, and a favorite speaker at specialties and dog club events all over the country. It's a great honor for us to welcome him here tonight.
Dr. Hutch is a Reproduction and Genetics consultant for the Veterinary Information Network, and is co-director of the Animal Clinic Northview, Inc., in North Ridgeville, Ohio.
He is also the president of the International Canine Semen Bank of Ohio, and advisor for College of Veterinary Medicine students interested in small animal theriogenology from Ohio State University, Virginia Tech, Purdue, Tufts, and Michigan State University.
Dr. Hutch is the author of many articles on canine reproduction in various breed journals and magazines, including "Canine Frozen Semen," "Improving the Odds of Having Healthy Puppies," "Treatment of Pyometritis in the Bitch Using Prostaglandin F - a Hypo-thyroidism," and "Female Reproduction." Dr. Hutch will open with a few remarks and then he will take your questions. To ask a question, just click on "AskDrHutch" in the right hand column, type your question, and hit "send."
If you have problems during the chat, just click on any of the names that begin with "@PCF" then type the question and hit "send."
I am very happy now to turn the seminar over to Dr. Hutch!
DrHutch: What a wonderful way to spend a winter evening! I thank everyone for their interest in canine reproduction. I especially want to thank Karen Copley and Whelpwise for their sponsorship and Christie Keith from VIN for her help.
For those that do not know me, I am tall, extremely handsome with wavy dark hair. For those of you who do know me, yes, I am still short, bald and dumpy! I do want to thank those who have attended my repro/pediatric seminars for their kind words on the message posts. Your questions have been excellent and very stimulating. I hope to cover as many as possible this evening.
For us to understand canine reproduction, we must realize that the canine, and especially the bitch, is a unique individual when compared to all other domestic species. While most animals ovulate into an estrogen bath, the bitch ovulates into a progesterone environment. This fact is why we cannot use estrogen testing, vaginal smears or breeding guns for other than general timing of the bitch's estrous cycle.
The use of frozen semen and fresh-cooled semen showed us the true facts of canine breeding. Many testing methods that seemed to work only appeared so due to the extreme long life of fresh semen in the bitch.
I always pictured Mother Nature looking at us dog breeders and saying "those poor, poor fools. They don't have a clue what they are doing!" Progesterone testing has allowed us to anticipate ovulation, determine whelping dates and to schedule planned c-sections months in advance.
Interpreting progesterone levels, unfortunately is still a mystery to many veterinarians and breeders. With these facts in place let's talk about your problems, concerns and interests!
Question: When you say "The use of frozen semen and fresh-cooled semen showed us the true facts of canine breeding. Many testing methods that seemed to work only appeared so due to the extreme long life of fresh semen in the bitch," what do you mean?
DrHutch: Basically, fresh semen lasts 5-6 days. Colorado state has found live semen ELEVEN days after breeding. This made up for a lot of our mistakes. Once we started using fresh cooled and semen, which last only a few days or hours, suddenly things that seemed to work in the past no longer seemed to work. Now with prosterone testing, we can get 83 percent conception rates with FROZEN semen....
Question: Bitches who keep missing.
Several people asked a variation of this question:
I have tried a number of times to breed my bitch, both with natural breedings and with AIs. She has missed repeatedly. Where do you start when trying to understand and resolve this problem?
DrHutch: Basically there are only SIX reasons a bitch misses, and we run around testing thyroid and doing cultures, which are really only minimal reasons for failure.
First, is the male sperm good.
Second, did she ovlulate.
Three, was semen put in at the right time.
Four, did semen get to egg.
Five, did fertilized egg implant.
Six, did placenta develop enough to maintain (the pregnancy).
We have to work our way through the list to determine what the cause was. What we do is, first of all, have the male semen evaluated. That is NOT saying there is a drop of sperm on the slide, there is sperm or no sperm.
Normal sperm evaluations consist of 10 million sperm per pound of body weight, 80 percent motility, less than 20 percent abnormal, and if your male sperm meets those criteria, probably it's not the problem.
The other five problems have to do with the bitch herself, and progesterone testing the DAY of ovulation is the day her progesterone goes above 5 nanograms. Even though she has this three week-plus heat cycle, there is a three to four day window we have to hit that varies from bitch to bitch. With progesterone testing, we can be sure the semen is put in at the proper time no matter what type of insemination method we are using.
In the bitch, the semen is pumped up into the uterus....so outside ties... poorly done AIs... that don't deposit the semen in the cervix, which is located in the abdomen above the bladder, prevent sement from being drawn up into the uterus.
As bitches age, they get cysts within their uterus which can obstruct the pathway - a good reason in an older bitch for considering a surgical insemination.
Conception takes place in the Fallopian Tubes regardless of the method of insemination.
An older bitch is any bitch over 5, by the way; several of you asked.
The fertilized eggs are then released into the uterus, but don't implant until day 17-18 after ovulation. So if there are uterine lining problems, we either don't have implantation OR...the placenta, which actually grows into the lining of the uterus, can't grow or be maintained, and the puppies are reabsorbed. It will develop as the night goes on, how to detect some of these problems.
When a bitch ovulates, whether we breed her, don't breed her, or pretend she's not in season, the progesterone HAMMERS the uterine lining for sixty-plus days.
The progesterone level is NOT affected by pregnancy. In the cow for example, if the uterus does not get communication from the fertilized egg by day 16, the whole process starts over again. In the bitch, you don't have that luxury.
Even though the bitch's body produces the progesterone, the progesterone is inflammatory to the uterine lining, so that after a heat cycle, the bitch's uterus is never as healthy as it was before the heat cycle. So we go from a normal uterus... and this start's with the first cycle of her life...to an endometritis to endometrial hyperplasia, which some of you have been asking about - this is when the uterus starts to thicken and we start to get bubbles in the lining of the uterus - these changes affect the uterine lining so much so that eventually the uterus cannot control the bacteria, and the ultimate end stage is pyometritis.
So, in the bitch... So breeding back to back... or even back to back to back to back....this is WHY it's such a crime we don't have Cheque drops on the market now, to preserve the bitch's uterine lining.
Several of you have asked when they will be back on the market....one company promised by this spring.
Pyometritis is a hormonal disease, of which the infection is only secondary. Cheque drops is a wonderful product.... that was Miberolone...a male hormone derivative that could safely delay a bitch coming in season for up to two years. Ovaban is a different product, same as human Megace. These are progesterone products, the exact hormone we are trying to preserve our uteruses from.We should NEVER use ovaban or megace in a bitch we want to breed in the future.
Cheque drops are NOT progesterone.We could show bitches, we could field trial bitches, and still have a uterus that was only 2-3 years old in a five year old bitch!Cheque drops preserve and promote fertility by preserving the uterine lining.
The average bitch after going off Cheque drops came in after 70 days. The biggest problem is they had to be given every day.
Pyo is EXTREMELY rare in a young bitch; remember, bitches do not go into menopause. Only humans and gorillas do.When a bitch's reproductive life is over she should be spayed.It's very good to spay an older bitch, because the uterus is always going to be hammered by progesterone every heat cycle.
Side effects from Cheque drops: One percent tear from the eyes; they tend to muscle up and get more coat, because it's a male hormone derivative. The biggest misunderstood side effect, however, was mucous around the vulva... like a puppy vaginitis.
Unfortunately, many veterinarians diagnose any goop around the vulva as pyometritis. Cheque drops PREVENTED pyometritis by protecting the uterine lining. Cheque drops were only removed from the market because they were not profitable enough. There was no medical reason.
Case History, STUD DOG:
Proven stud dog who was recently diagnosed as being sterile. .He is being treated for a prostate infection using Orbax 68mg for 2 weeks. Vet found prostate normal on exam but lots of bright red blood in semen. Will we be able to restore fertility? Thoughts?
DrHutch: Male dogs age the same as human males age... with a change in the type testosterone being produced from the testicles.
One of the effects in the dog is benign prostatic hyperplasia (bigger prostate). This is a routine happening in all males over six years of age, being especially prominent in the Doberman.
Unfortunately, it is misdiagnosed as an infectious process by many veterinarians. So they often times are treated by antibiotics, often with no subsequent improvement with often the drastic suggestion that the male be neutered. The PROPER treatment is one of hormone therapy, using one of two products: either Ovaban, that dreaded product we wouldn't use in the bitch, or Proscar, which is finasteride, which is a human product.
These work by countering the change of the testosterone causing the prostate to shrink back down to a normal size, stopping the bleeding, making the dog reproductively normal. A dog with a prostate INFECTION will have PUS in the ejaculate, not blood. A dog with a true prostate infection runs a fever, or shows many of the signs of a bitch with pyometritis. Prostatic cancers do occur in the dog, but are more common in neutered dogs than in non-neutered dogs.
Question: Is is safe to breed a bitch the next season after stopping the Cheque?
DrHutch: Absolutely. It's suggested not to skip a season, because we have been preserving the uterus from the effects of progesterone; what would be the benefit of exposing her uterus to two monts of progesterone?
Progesterone's effect on the uterine lining is the reason why bitches six and over have a 33.3 percent less chance of conceiving than bitches under 6 years of age.
Back to the case study.... neutering does not cause prostatic cancer....but it does not prevent it.
I'm getting many questions on Ovaban.
Ovaban will decrease the amount of blood and prostatic fluid, not actually INCREASE sperm. The treatment is a daily treatment for 3 weeks; after that once a week indefinitely. It's a control medication countering the aging and hormonal changes of the testicle.
80 percent of a dog's sperm production is based on the size of their testicles; that's where we get the 10 million per pound of body weight. Changes can take place due to cortisol, from STRESS... we don't appreciate the effect of stress on the reproductive health of our dogs. Interestingly THYROID has little to do with the reproductive health of our dogs (males)a study at Michigan State took male dogs and completely destroyed their thyroid and found it had no effect on sperm production.
The thyroid is probably not a consideration in a dog with a low sperm count. We should look for hormonal problems in the body, infection problems in the body. And in many dogs, immune and genetic problems.
Thyroid in bitches also has very little importance in reproduction. The main sign of a reproduction problem related to female hypothyroid is they don't come in season. There is no proven benefit of giving thyroid to a normal thyroid individual, reproductively. My main concern with thyroid, depending on which of the three types of hypothyroidism it is, is the immune-mediated type has genetic implications.
If they have even SOME thyroid, that is probably all that is needed to maintain a pregnancy. Studies out of Florida show bitches with even ZERO thyroid function, did have trouble maintaining a pregnancy and had a type of dwarf puppy, but bitches with ANY thyroid function, that come into season, thyroid will probably not cause any further problems.
So once you've proven your bitch's thyroid is normal, there is no reason to be going to six different veterinarians to have her retested. Save your money, take Dr. Hutchison to lunch
Question: What about the dreaded mycoplasma?
DrHutch: Unfortunately, an article published in the early 90s blamed mycoplasma for infertility in males, bitches aborting their puppies, husbands fooling around with their secretaries.
We as dog people jumped on this like there was no tomorrow. Mycoplasma is a normal organism at all body openings. A routine culture of a bitch's vaginal tract will show strep, staph, e coli, pastuerella, and mycoplasma. The vaginal tract is not sterile so routine culturing of a normal, healthy bitch is totally unwarranted.
You need to appreciate the purpose of normal flora or normal bacteria: they keep the BAD bugs out so a routine culture, that shows mycoplasma, e coli, and strep, is not a cause for treatment but a cause for celebration because the bitch is normal
Question: What about bitches who did not become pregnant before antibiotics, but do afterward?
DrHutch: Putting on bitches on antibiotics pre-breeding actually makes them more prone to infectious disease by killing normal organisms, especially when we use the GOOD drugs like Baytril. Occasionally, we may see a bitch with an infection... but there will be signs of that infection - redness, abnormal discharge, smelling - just like if you have an infection in your ear, you're not going to not know it. Bacteria does not equal infection.
When we see problems with mycoplasma, for example, it is not the mycoplasma that caused the problem. Mycoplasma only took the opportunity of the infection, just the same as the staph on the skin causes a hot spot because the dog has fleas, for example. Most of the individuals that see who do have mycoplasma infection, would not have been prevented by a routine culture, as the primary problem was stress, steroids, or other types of immune deficiency. They are only secondary problems. Something like pyometritis is not caused by routine bacteria; the normal bacteria were allowed to flare up by the inflammation of the uterine lining
Question: Isn't it true that an e coli infection can be passed to the puppies in the birth canal, causing fading puppies and the loss of the whole litter?
DrHutch: In normal healthy puppies, no. Think of puppies like the lions surrounding the antelopes looking for the weak ones. If a puppy is stressed, unhealthy, otherwise compromised, then the e coli can flare up but it's not because we allowed the e coli to be there, it's because we allowed the puppy to be uhhealthy.
We cannot sterilize vaginal tracts no matter how many antibiotics we give because air goes in, air goes out. Just because there is vaginal bacteria does not mean there is intrauterine bacteria (bacteria in the uterus).
I want to say I LOVE LOVE LOVE these questions!
New question: Can't these bacteria be transmitted to the stud dog?
DrHutch: The male HAS all of these organism, so no, they are NOT contagious. This is why one of the most absolute crazy things I have ever heard of, is people treating their whole kennel because they had one dog with mycoplasma. This would be the equivalent of treating your whole kennel because one dog had a hot spot. Every dog has this. It's not contagious.
Brucellosis.... is a whole other world.
Brucellosis is NOT a normal organism of the male or the female. Brucellosis is a very serious disease that all bitches should be tested for every time they are going to be bred, and males should be tested for every six months if they only breed a negative female.
Brucella bacteria can be passed through all body discharges, not just through breeding, so even individuals that have never been bred but who have been to a show, a kennel, a field trial, need to have a negative brucellosis test.
Brucellosis is not common, but because it is extremely deadly... I myself consulted with a kennel a few years ago who put down 26 dogs because of an infected male they brought in. It is a serious disease which is primarily associated in the bitches with aborting puppies, and in the male causing inflammation of the testicles and subsequent infertility.
It is at this point not curable to the point of returning to reproduction. Do not wait until the last minute to have your brucella test run becasue the slide test run by veterinarians in their office, actually made from sheep brucellosis, one dog out of five has a false positive.
Even with AIs, you can protect the male, but not the female, from a dog who has brucella. Because you put the prostatic fluid and ejaculate into the bitch, along with the brucella. When we freeze semen, it is critical to us to be certain the male is negative for brucellosis, so we aren't preserving these bacteria for a thousand years!
Most dogs (with brucellosis) do not have to be put down, but they must be neutered and put on antibiotics for 4-5 years. And it is transmissable to humans too.
These questions are SO GREAT... they are fabulous!
Question: Herpes?
DrHutch: Herpes is not the same as brucellosis. It is part of the kennel cough complex. Any dog who has been to a show or a training class probably has herpes virus. Herpes virus is common. That is why it is rare having a problem with it. Herpes virus is only deadly to puppies during the first three weeks of life, because a newborn puppy's average body temperature does not reach 100 degrees until 3 weeks of age. If the bitch has never been exposed to herpes, and has no antibodies to pass through the colostrum to the puppies, the puppies could be affected.
Once a bitch has a litter with herpes, she will have the antibodies to pass through the colostrum to the next puppies, so they will be protected. Many people believe that a bitch should be taken to shows etc so they are exposed and have the protection to pass on to their puppies.
Puppies can be infected in utero, through the vaginal tract, or by other dogs coming to sneeze on them. Isolation is a good idea for the first three weeks.
Treatment for herpes: raise the body temperature to 100 degrees, herpes goes from being a deadly to virus to causing nothing more than a minor cough.
Question: Comparing AI methods
Can you compare the success rates of fresh chilled vs. frozen semen, and surgical implant vs AI vs transcervical insemination?
DrHutch: The type of insemination method depends on two things: Age of the bitch and health of the semen you put in. Unfortunately, a misnomer exists that the transcervical insemination replaces surgical insemination. This is totally false. Transcervical insemination improves upon VAGINAL artificial insemination, it does not replace the surgical.
In a regular AI, vaginal, the semen is deposited at the entrance to the cervix, the tie is simulated. often by taking a rubber glove and stroking the vaginal tract, which causes oxytocin release. which causes the semen to be pumped up to the uterus. So we know compromised (frozen) semen, which is weaker and will only live about 12 hours, needs to be deposited into the uterus. Conceptions rates from frozen semen put in vaginally are 11 percent Conception rates from frozen semen put into the uterus are 83 percent.
The transcervical is taking an endoscope, visualizing the entrance to the cervix, and putting a catheter through the cervix and putting the semen into the uterus. It does not require anesthetic; the bitch just stands there. In our practice we just watch it on television... better than watching Oprah.
The drawback to a transcervical insemination is you don't get a chance to evaluate the uterus. In a surgical insemination, I have the uterus in my hand. I can feel for cysts, I can visualize where to put the semen. In many cases, by breaking down cysts, I can take conception rates from zero percent to 100 percent.
Using fresh semen in a young bitch is still a regular vaginal AI. Compromised semen which is either poor quality semen, fresh cooled semen, or frozen semen, in a young bitch, should be transcervical insemination. Using poor quality semen in a bitch 4 and a half to five years or older, you want to do a surgical insemination so the uterus can be evaluated.
A surgical insemination is always your greatest chance of having puppies.
Question: Do we need to spin down the semen for a transcervical insemination?
DrHutch: Since the uterus only holds less than a teaspoon, we will oftentimes centrifuge the semen so that the whole volume will stay in the uterus rather than running out through the cervix.
Because the cervix is open in a bitch in season, bacteria can go back and forth into the uterus, so the transcervical insemination does NOT introduce more bacteria than normal into the uterus, no matter which insemination is used, including natural.
Conception occurs from all of these in the same place, the Fallopian tubes, so the method of insemination does not alter the location of the puppies in the uterus, the lack of ease of delivery, or positioning of the puppies.
Question: What part of the ejaculate is the semen in?
DrHutch: The male ejaculates in three distinct fractions. The first fraction just cleans the pipes. The second fraction contains the sperm; that's the part that should look milky and thick. You stop collecting when you see the prostatic fluid, which looks like water. Volume is not important; no one has a trophy for collecting a quart of dog semen.
Question: How is a surgical AI done?
DrHutch: A surgical insemination is a minor procedure that is done under an anesthetic. I use propofol and sevothane, the same anesthetics we use for c-sections, for our surgical Ais. The procedure lasts approximately ten minutes. I make an incision into the abdomen, like a mini mini spay incision - unless I sneeze, then it gets bigger - then I isolate the uterus in my hand. The semen is injected into the uterus using a 22 guage needle, the same size needle used for vaccine. This will not negatively impact future breedings.
It is SO COOL because I can see the uterus fill with the semen; it's like watching the Discovery Channel.
I put in three stiches, five staples, the whole procedure from the time she walks in the door is less than an hour.
Question: How long does frozen semen last, stored?
DrHutch: Frozen semen lasts stored, probably forever. It uses minimal energy when it's stored in the liquid nitrogen at minus 322 degrees F. We had a litter recently from semen that had been stored 25 years, it looked just as good as the day it was frozen. It was great to see the sperm swimming around again, happy to be warm!
The way we package our frozen semen is by the number of normal live sperm cells per dose. A dog with a great sperm count may get multiple multiple breedings out of each collection... a dog with lower sperm count may get one. We calculate our dose so that each breeding has a set number of live normal sperm, rather than by volume or by a set number.
Question: When there is a poor semen sample, is there a way to isolate the viable sperm?
DrHutch: We don't worry about the abnormal sperm, other than mathematically eliminating them, because abnormal sperm does not cause abnormal puppies, so there is no reason to eliminate them
Question: Oxytocin (Pit shots).
Can you discuss the proper use of oxytocin injections during whelping? It seems that many breeders use oxytocin early on in the whelping process, when they feel it isn't progressing fast enough.
DrHutch: A puppy in the uterus has only two elements maintaining its oxygenation and life, one being the heartrate of the puppy, two being the blood pressure from mom to the uterus.
The whole goal in whelping is to maintain vital elements. Oxytocin I use in a very specific manner. If you've gone three hours without a puppy, I use one dose of oxytocin. My dose of oxytocin is two units per ten pounds of body weight. Oxytocin is normally 20 units per ml; I never use more than half an ml, no matter how big the bitch is.
I give one injection; if nothing happens, I give a second injection 20 minutes later. If nothing happens, I go to a C-section.
If you get too much oxytocin at a time, you will cause the puppies not to be expelled from the uterus but shrunk wrapped IN the uterus. The two injections of oxytocin actually increase the blood pressure to uterus which is beneficial to the puppies. If we keep giving them, we LOWER the blood pressure to the uterus, which robs the puppies of oxygen.
Using calcium with the oxytocin... now that we can monitor calcium levels in our practice I do not normally give calcium if the bitch is normal, because it causes the heart to slow down. If I need to give calcium I now use Calsorb, an oral gel that is absorbed almost as quickly as injectable. I can give it in small amounts more often, and don't have to worry about the side effects of injected calcium.
To clarify, my standard protocol (with oxytocin) is two injections; if two don't do it, two, four, ten, twenty, is not going to do it. In most cases I keep score by how many live puppies I deliver, not how many C-section
I avoid. I wait three hours from the last puppy.
My signs of dystocia are:
Temp just before labor readjusts back up to normal;
If I have no puppy born in four hours.
That is my definition of primary uterine inertia.
Straining hard for an hour... that is when you would NOT give oxytocin. Longer than three hours between puppies, that's when you DO give oxytocin.
Any black, red, or green discharge before any puppies are delivered indicates placental detachment and needs attention.
Ultrasounds, fetal monitoring devices, are critical to determine fetal well being. The ability to monitor the fetal heart rate is essential with WhelpWise or having an ultrasound.
I have worked and consulted with breeders using WhelpWise; it's ESPECIALLY important if a veterinarian does not have ultrasound, because there is no other way to monitor the whelps and fetal health
Question: What is WhelpWise?
DrHutch: WhelpWise is the sponsor of this event, actually... it is a fetal monitoring service. You can monitor your bitch's labor progression and fetal heart beat at home. They work well with your veterinarian. They are at http://www.whelpwise.com. Thank you Karen! Karen Copely, the owner and founder of WhelpWise.
I believe that we have the right to expect every puppy that our bitch carries; I am not one who believes you get a litter because you expect to throw one away. The ones we work the hardest on, often turn out to be the best!
Question: Is there any reason to suspect ultrasound causes reabsorption of puppies?
DrHutch: Ultrasounding is normally done day 26-28, when the heart starts beating on the puppy, so we can monitor viability as well as pregnancy. Absorption can occur up until around day 37-38.
Now that we are ultrasounding, we are REALIZING that absorption is not uncommon in the bitch, but ultrasound is only diagnosing it, it's not causing it. Just as x-raying a bitch at day 52 does NOT cause cataracts or whatever in the bitch; it gives us a WHALE of a lot of information about how many pups, their size, their positioning , and their health. That is an urban legend.
Absorption is most commonly caused when the uterus is not able to support the placenta and give nutrition to the puppies; genetic problems that stop the puppies from developing; there can be some viral of infectious causes; there have been some toxins identified in large animals more so than in small animals. Trauma probably plays no role, such as palpation or jumping off the porch.
Question: Reliability of progesterone testing?
I have seen the progesterone testing of a bitch to determine ideal breeding times, to be off by as much as three days.....according to my stud dog...and the successful breeding LATER than the test suggested. Care to comment on this???
DrHutch: It is best if one can obtain progesterone numbers, which should not be a problem in this day and age. Progesterone tests are not species specific, so can be run in human labs, dog labs, horse labs.
The biggest mistake people make in running progesterone tests is they stop before the progesterone goes above five nanograms. The day the progesterone goes above five nanograms is the day of ovulation. The whole world revolves around five nanograms.
The fact that we could determine just the initial rise (rise to 2-3 nanograms of progesterone) is a total fallacy. You must confirm ovulation. I start testing around day 6 of the cycle. You need to run your progesterone every 2-3 days.
Question: What is the most reliable in house test?
DrHutch: At this point, I recommend you find an outside lab to give you a number, as opposed to running in house tests; they are not as accurate.
Question: Doesn't the time lag cause a problem?
DrHutch: You should be able to get the results back in 24 hours max. If there IS a time lag problem, check with a human hospital, or if nothing else, overnight them to me! I can have them that same afternoon!
Question: What about the LH surge?
DrHutch: Because the LH test has to be run every day, and LH is species specific, and in most cases even running the LH we still put most faith in the progesterone tests, I do not run the LH except in very, very specific cases. And the bitches appreciate not being BLED every day for 14 days in a row.... the urine LH is not successful.
Question: What about supplementing progesterone?
DrHutch: The bitch's sole source of progesterone is the ovary. She does not switch the source of progesterone to the placenta like the horse or the cat, therefore it is very uncommon for a bitch to lose a litter due to a premature drop in progesterone.
Giving progesterone when it's not needed will cause birth defects in the female puppies.
If we need to supplement progesterone, I use progesterone in oil injections, as they do show up on progesterone tests, which tells us when to give the next dose. There is an oral synthetic progesterone called Regumate which is used on horses. It will not show up on progesterone tests and therefore will not be monitored.
We only need 2 and one half nanograms of progesterone to maintain a pregnancy. Most bitches during a pregnancy have 8-10 times that amount. A bitch dropping from 20 nanograms to 15 nanograms would still have plenty, and you would definitely not supplement.
I only supplement if the bitch drops lower than 5 nanograms and we have longer than 7 days to our anticipated due date
The bitch's due date, 63 days from her ovulation date, the date she went above 5 nanograms progesterone. Breeding date has nothing to do with whelping date It's the OVULATION date. So if you know the day your bitch goes above 5 nanograms, you can set her due date at 63 days from that as her whelping date: set up your whelping box, take the day off work.
Question: After progesterone reaches 5 nanograms, what are the best days for breeding?
DrHutch: The bitch ovulates an immature egg that has to mature for 48 hours before it can be fertilized. The breeding depends on the anticpated life of semen. A natural breeding can be done the day of 5 nanograms, the day after... the life of the semen is going to cover it. The fresh cooled semen should be 48 hours after 5 nanograms. Frozen, we breed 72 hours after 5 nanograms, because frozen semen only lives 12 hours. Slightly later is better than slightly early because you want the egg to be ready to be fertilized.
Question: Dr. Hutchison, are we intervening too much and harming our breeds with all these AIs, surgical inseminations, etc?
DrHutch: I don't believe that ignoring technicological advances, advances our breeding. I believe anything we can do to make breeding successful, like using frozen semen... is good. Anything we can do to improve our dog breeding and have more live, healthy puppies, interventions in safe, healthy manners, can only be a positive.
I think the Cornell study that showed you get more live puppies from a c-section, showed us that intervention can be a benefit by saving those normal puppies who by some reason cannot get through the birthing process.
Being able to go back to breed to frozen semen from a dog from 25 years ago can only be a positive thing, bringing some of those lost traits back into our lines Plus I need to do this, I have a high maintanance wife.
There were so many great questions, but we have just run out of time... we will have more information in a follow up email... but I just love you guys - you ask the best and the greatest questions and I would like to get to each and every one of them.
So many exciting things lie ahead for us dog breeders. Embryo transfer, in-vitro fertilization, frozen ova to name a few. Yet, I always am amazed at the number of people, especially veterinarians, critical of us for wanting to breed our bitches. They blame us for the great pet over-population problems, like breeding uncontrolled, mixed breeds is our goal.
Go forth, improve your breeds, and good luck on your next litter, it may contain the best one ever!!
Thank you, Thank you, Thank you!!! Good night.
PCFFasDog: The Pet Care Forum and Veterinary Information Network thank all of you for attending this event tonight, and hope you enjoyed it. We especially want to thank Dr. Hutch for giving so generously of this time and information, and of course, to thank Veterinary Perinatal Specialties at http://www.whelpwise.com for their sponsorship. This event would not have been possible without them!
Goodnight and thank you again!
DrHutch: Thanks everyone!
Dr. Hutchison gives his permission for dog clubs to reprint this article in their club newsletters or publications provided the following statement is included:
Copyright 2002 by Dr. Robert Hutchison and the Veterinary Information Network, Inc. Used with permission. All rights reserved. Dr. Van Hutchison can be reached at Animal Clinic Northview, Inc., 34910 Center Ridge Rd., North Ridgeville, Ohio 44039; (440) 327-8282.
Date Published: 8/19/2002 1:42:00 PM
http://www.veterinarypartner.com/Content.plx?A=1224
DrHutch: Good evening!
PCFFasDog: Good evening and thank you all for being here! We are very excited to welcome Dr. Robert Van Hutchison to our first Canine Reproduction Seminar.
This free seminar is sponsored by Veterinary Perinatal Specialties, Inc., home of the WhelpWise service. Please visit their website at http://www.whelpwise.com, and show your support for their sponsorship of this event!
Many of you already know Dr. Hutchison or have seen him speak in person. He is one of the leading canine reproduction experts in the world, and a favorite speaker at specialties and dog club events all over the country. It's a great honor for us to welcome him here tonight.
Dr. Hutch is a Reproduction and Genetics consultant for the Veterinary Information Network, and is co-director of the Animal Clinic Northview, Inc., in North Ridgeville, Ohio.
He is also the president of the International Canine Semen Bank of Ohio, and advisor for College of Veterinary Medicine students interested in small animal theriogenology from Ohio State University, Virginia Tech, Purdue, Tufts, and Michigan State University.
Dr. Hutch is the author of many articles on canine reproduction in various breed journals and magazines, including "Canine Frozen Semen," "Improving the Odds of Having Healthy Puppies," "Treatment of Pyometritis in the Bitch Using Prostaglandin F - a Hypo-thyroidism," and "Female Reproduction." Dr. Hutch will open with a few remarks and then he will take your questions. To ask a question, just click on "AskDrHutch" in the right hand column, type your question, and hit "send."
If you have problems during the chat, just click on any of the names that begin with "@PCF" then type the question and hit "send."
I am very happy now to turn the seminar over to Dr. Hutch!
DrHutch: What a wonderful way to spend a winter evening! I thank everyone for their interest in canine reproduction. I especially want to thank Karen Copley and Whelpwise for their sponsorship and Christie Keith from VIN for her help.
For those that do not know me, I am tall, extremely handsome with wavy dark hair. For those of you who do know me, yes, I am still short, bald and dumpy! I do want to thank those who have attended my repro/pediatric seminars for their kind words on the message posts. Your questions have been excellent and very stimulating. I hope to cover as many as possible this evening.
For us to understand canine reproduction, we must realize that the canine, and especially the bitch, is a unique individual when compared to all other domestic species. While most animals ovulate into an estrogen bath, the bitch ovulates into a progesterone environment. This fact is why we cannot use estrogen testing, vaginal smears or breeding guns for other than general timing of the bitch's estrous cycle.
The use of frozen semen and fresh-cooled semen showed us the true facts of canine breeding. Many testing methods that seemed to work only appeared so due to the extreme long life of fresh semen in the bitch.
I always pictured Mother Nature looking at us dog breeders and saying "those poor, poor fools. They don't have a clue what they are doing!" Progesterone testing has allowed us to anticipate ovulation, determine whelping dates and to schedule planned c-sections months in advance.
Interpreting progesterone levels, unfortunately is still a mystery to many veterinarians and breeders. With these facts in place let's talk about your problems, concerns and interests!
Question: When you say "The use of frozen semen and fresh-cooled semen showed us the true facts of canine breeding. Many testing methods that seemed to work only appeared so due to the extreme long life of fresh semen in the bitch," what do you mean?
DrHutch: Basically, fresh semen lasts 5-6 days. Colorado state has found live semen ELEVEN days after breeding. This made up for a lot of our mistakes. Once we started using fresh cooled and semen, which last only a few days or hours, suddenly things that seemed to work in the past no longer seemed to work. Now with prosterone testing, we can get 83 percent conception rates with FROZEN semen....
Question: Bitches who keep missing.
Several people asked a variation of this question:
I have tried a number of times to breed my bitch, both with natural breedings and with AIs. She has missed repeatedly. Where do you start when trying to understand and resolve this problem?
DrHutch: Basically there are only SIX reasons a bitch misses, and we run around testing thyroid and doing cultures, which are really only minimal reasons for failure.
First, is the male sperm good.
Second, did she ovlulate.
Three, was semen put in at the right time.
Four, did semen get to egg.
Five, did fertilized egg implant.
Six, did placenta develop enough to maintain (the pregnancy).
We have to work our way through the list to determine what the cause was. What we do is, first of all, have the male semen evaluated. That is NOT saying there is a drop of sperm on the slide, there is sperm or no sperm.
Normal sperm evaluations consist of 10 million sperm per pound of body weight, 80 percent motility, less than 20 percent abnormal, and if your male sperm meets those criteria, probably it's not the problem.
The other five problems have to do with the bitch herself, and progesterone testing the DAY of ovulation is the day her progesterone goes above 5 nanograms. Even though she has this three week-plus heat cycle, there is a three to four day window we have to hit that varies from bitch to bitch. With progesterone testing, we can be sure the semen is put in at the proper time no matter what type of insemination method we are using.
In the bitch, the semen is pumped up into the uterus....so outside ties... poorly done AIs... that don't deposit the semen in the cervix, which is located in the abdomen above the bladder, prevent sement from being drawn up into the uterus.
As bitches age, they get cysts within their uterus which can obstruct the pathway - a good reason in an older bitch for considering a surgical insemination.
Conception takes place in the Fallopian Tubes regardless of the method of insemination.
An older bitch is any bitch over 5, by the way; several of you asked.
The fertilized eggs are then released into the uterus, but don't implant until day 17-18 after ovulation. So if there are uterine lining problems, we either don't have implantation OR...the placenta, which actually grows into the lining of the uterus, can't grow or be maintained, and the puppies are reabsorbed. It will develop as the night goes on, how to detect some of these problems.
When a bitch ovulates, whether we breed her, don't breed her, or pretend she's not in season, the progesterone HAMMERS the uterine lining for sixty-plus days.
The progesterone level is NOT affected by pregnancy. In the cow for example, if the uterus does not get communication from the fertilized egg by day 16, the whole process starts over again. In the bitch, you don't have that luxury.
Even though the bitch's body produces the progesterone, the progesterone is inflammatory to the uterine lining, so that after a heat cycle, the bitch's uterus is never as healthy as it was before the heat cycle. So we go from a normal uterus... and this start's with the first cycle of her life...to an endometritis to endometrial hyperplasia, which some of you have been asking about - this is when the uterus starts to thicken and we start to get bubbles in the lining of the uterus - these changes affect the uterine lining so much so that eventually the uterus cannot control the bacteria, and the ultimate end stage is pyometritis.
So, in the bitch... So breeding back to back... or even back to back to back to back....this is WHY it's such a crime we don't have Cheque drops on the market now, to preserve the bitch's uterine lining.
Several of you have asked when they will be back on the market....one company promised by this spring.
Pyometritis is a hormonal disease, of which the infection is only secondary. Cheque drops is a wonderful product.... that was Miberolone...a male hormone derivative that could safely delay a bitch coming in season for up to two years. Ovaban is a different product, same as human Megace. These are progesterone products, the exact hormone we are trying to preserve our uteruses from.We should NEVER use ovaban or megace in a bitch we want to breed in the future.
Cheque drops are NOT progesterone.We could show bitches, we could field trial bitches, and still have a uterus that was only 2-3 years old in a five year old bitch!Cheque drops preserve and promote fertility by preserving the uterine lining.
The average bitch after going off Cheque drops came in after 70 days. The biggest problem is they had to be given every day.
Pyo is EXTREMELY rare in a young bitch; remember, bitches do not go into menopause. Only humans and gorillas do.When a bitch's reproductive life is over she should be spayed.It's very good to spay an older bitch, because the uterus is always going to be hammered by progesterone every heat cycle.
Side effects from Cheque drops: One percent tear from the eyes; they tend to muscle up and get more coat, because it's a male hormone derivative. The biggest misunderstood side effect, however, was mucous around the vulva... like a puppy vaginitis.
Unfortunately, many veterinarians diagnose any goop around the vulva as pyometritis. Cheque drops PREVENTED pyometritis by protecting the uterine lining. Cheque drops were only removed from the market because they were not profitable enough. There was no medical reason.
Case History, STUD DOG:
Proven stud dog who was recently diagnosed as being sterile. .He is being treated for a prostate infection using Orbax 68mg for 2 weeks. Vet found prostate normal on exam but lots of bright red blood in semen. Will we be able to restore fertility? Thoughts?
DrHutch: Male dogs age the same as human males age... with a change in the type testosterone being produced from the testicles.
One of the effects in the dog is benign prostatic hyperplasia (bigger prostate). This is a routine happening in all males over six years of age, being especially prominent in the Doberman.
Unfortunately, it is misdiagnosed as an infectious process by many veterinarians. So they often times are treated by antibiotics, often with no subsequent improvement with often the drastic suggestion that the male be neutered. The PROPER treatment is one of hormone therapy, using one of two products: either Ovaban, that dreaded product we wouldn't use in the bitch, or Proscar, which is finasteride, which is a human product.
These work by countering the change of the testosterone causing the prostate to shrink back down to a normal size, stopping the bleeding, making the dog reproductively normal. A dog with a prostate INFECTION will have PUS in the ejaculate, not blood. A dog with a true prostate infection runs a fever, or shows many of the signs of a bitch with pyometritis. Prostatic cancers do occur in the dog, but are more common in neutered dogs than in non-neutered dogs.
Question: Is is safe to breed a bitch the next season after stopping the Cheque?
DrHutch: Absolutely. It's suggested not to skip a season, because we have been preserving the uterus from the effects of progesterone; what would be the benefit of exposing her uterus to two monts of progesterone?
Progesterone's effect on the uterine lining is the reason why bitches six and over have a 33.3 percent less chance of conceiving than bitches under 6 years of age.
Back to the case study.... neutering does not cause prostatic cancer....but it does not prevent it.
I'm getting many questions on Ovaban.
Ovaban will decrease the amount of blood and prostatic fluid, not actually INCREASE sperm. The treatment is a daily treatment for 3 weeks; after that once a week indefinitely. It's a control medication countering the aging and hormonal changes of the testicle.
80 percent of a dog's sperm production is based on the size of their testicles; that's where we get the 10 million per pound of body weight. Changes can take place due to cortisol, from STRESS... we don't appreciate the effect of stress on the reproductive health of our dogs. Interestingly THYROID has little to do with the reproductive health of our dogs (males)a study at Michigan State took male dogs and completely destroyed their thyroid and found it had no effect on sperm production.
The thyroid is probably not a consideration in a dog with a low sperm count. We should look for hormonal problems in the body, infection problems in the body. And in many dogs, immune and genetic problems.
Thyroid in bitches also has very little importance in reproduction. The main sign of a reproduction problem related to female hypothyroid is they don't come in season. There is no proven benefit of giving thyroid to a normal thyroid individual, reproductively. My main concern with thyroid, depending on which of the three types of hypothyroidism it is, is the immune-mediated type has genetic implications.
If they have even SOME thyroid, that is probably all that is needed to maintain a pregnancy. Studies out of Florida show bitches with even ZERO thyroid function, did have trouble maintaining a pregnancy and had a type of dwarf puppy, but bitches with ANY thyroid function, that come into season, thyroid will probably not cause any further problems.
So once you've proven your bitch's thyroid is normal, there is no reason to be going to six different veterinarians to have her retested. Save your money, take Dr. Hutchison to lunch
Question: What about the dreaded mycoplasma?
DrHutch: Unfortunately, an article published in the early 90s blamed mycoplasma for infertility in males, bitches aborting their puppies, husbands fooling around with their secretaries.
We as dog people jumped on this like there was no tomorrow. Mycoplasma is a normal organism at all body openings. A routine culture of a bitch's vaginal tract will show strep, staph, e coli, pastuerella, and mycoplasma. The vaginal tract is not sterile so routine culturing of a normal, healthy bitch is totally unwarranted.
You need to appreciate the purpose of normal flora or normal bacteria: they keep the BAD bugs out so a routine culture, that shows mycoplasma, e coli, and strep, is not a cause for treatment but a cause for celebration because the bitch is normal
Question: What about bitches who did not become pregnant before antibiotics, but do afterward?
DrHutch: Putting on bitches on antibiotics pre-breeding actually makes them more prone to infectious disease by killing normal organisms, especially when we use the GOOD drugs like Baytril. Occasionally, we may see a bitch with an infection... but there will be signs of that infection - redness, abnormal discharge, smelling - just like if you have an infection in your ear, you're not going to not know it. Bacteria does not equal infection.
When we see problems with mycoplasma, for example, it is not the mycoplasma that caused the problem. Mycoplasma only took the opportunity of the infection, just the same as the staph on the skin causes a hot spot because the dog has fleas, for example. Most of the individuals that see who do have mycoplasma infection, would not have been prevented by a routine culture, as the primary problem was stress, steroids, or other types of immune deficiency. They are only secondary problems. Something like pyometritis is not caused by routine bacteria; the normal bacteria were allowed to flare up by the inflammation of the uterine lining
Question: Isn't it true that an e coli infection can be passed to the puppies in the birth canal, causing fading puppies and the loss of the whole litter?
DrHutch: In normal healthy puppies, no. Think of puppies like the lions surrounding the antelopes looking for the weak ones. If a puppy is stressed, unhealthy, otherwise compromised, then the e coli can flare up but it's not because we allowed the e coli to be there, it's because we allowed the puppy to be uhhealthy.
We cannot sterilize vaginal tracts no matter how many antibiotics we give because air goes in, air goes out. Just because there is vaginal bacteria does not mean there is intrauterine bacteria (bacteria in the uterus).
I want to say I LOVE LOVE LOVE these questions!
New question: Can't these bacteria be transmitted to the stud dog?
DrHutch: The male HAS all of these organism, so no, they are NOT contagious. This is why one of the most absolute crazy things I have ever heard of, is people treating their whole kennel because they had one dog with mycoplasma. This would be the equivalent of treating your whole kennel because one dog had a hot spot. Every dog has this. It's not contagious.
Brucellosis.... is a whole other world.
Brucellosis is NOT a normal organism of the male or the female. Brucellosis is a very serious disease that all bitches should be tested for every time they are going to be bred, and males should be tested for every six months if they only breed a negative female.
Brucella bacteria can be passed through all body discharges, not just through breeding, so even individuals that have never been bred but who have been to a show, a kennel, a field trial, need to have a negative brucellosis test.
Brucellosis is not common, but because it is extremely deadly... I myself consulted with a kennel a few years ago who put down 26 dogs because of an infected male they brought in. It is a serious disease which is primarily associated in the bitches with aborting puppies, and in the male causing inflammation of the testicles and subsequent infertility.
It is at this point not curable to the point of returning to reproduction. Do not wait until the last minute to have your brucella test run becasue the slide test run by veterinarians in their office, actually made from sheep brucellosis, one dog out of five has a false positive.
Even with AIs, you can protect the male, but not the female, from a dog who has brucella. Because you put the prostatic fluid and ejaculate into the bitch, along with the brucella. When we freeze semen, it is critical to us to be certain the male is negative for brucellosis, so we aren't preserving these bacteria for a thousand years!
Most dogs (with brucellosis) do not have to be put down, but they must be neutered and put on antibiotics for 4-5 years. And it is transmissable to humans too.
These questions are SO GREAT... they are fabulous!
Question: Herpes?
DrHutch: Herpes is not the same as brucellosis. It is part of the kennel cough complex. Any dog who has been to a show or a training class probably has herpes virus. Herpes virus is common. That is why it is rare having a problem with it. Herpes virus is only deadly to puppies during the first three weeks of life, because a newborn puppy's average body temperature does not reach 100 degrees until 3 weeks of age. If the bitch has never been exposed to herpes, and has no antibodies to pass through the colostrum to the puppies, the puppies could be affected.
Once a bitch has a litter with herpes, she will have the antibodies to pass through the colostrum to the next puppies, so they will be protected. Many people believe that a bitch should be taken to shows etc so they are exposed and have the protection to pass on to their puppies.
Puppies can be infected in utero, through the vaginal tract, or by other dogs coming to sneeze on them. Isolation is a good idea for the first three weeks.
Treatment for herpes: raise the body temperature to 100 degrees, herpes goes from being a deadly to virus to causing nothing more than a minor cough.
Question: Comparing AI methods
Can you compare the success rates of fresh chilled vs. frozen semen, and surgical implant vs AI vs transcervical insemination?
DrHutch: The type of insemination method depends on two things: Age of the bitch and health of the semen you put in. Unfortunately, a misnomer exists that the transcervical insemination replaces surgical insemination. This is totally false. Transcervical insemination improves upon VAGINAL artificial insemination, it does not replace the surgical.
In a regular AI, vaginal, the semen is deposited at the entrance to the cervix, the tie is simulated. often by taking a rubber glove and stroking the vaginal tract, which causes oxytocin release. which causes the semen to be pumped up to the uterus. So we know compromised (frozen) semen, which is weaker and will only live about 12 hours, needs to be deposited into the uterus. Conceptions rates from frozen semen put in vaginally are 11 percent Conception rates from frozen semen put into the uterus are 83 percent.
The transcervical is taking an endoscope, visualizing the entrance to the cervix, and putting a catheter through the cervix and putting the semen into the uterus. It does not require anesthetic; the bitch just stands there. In our practice we just watch it on television... better than watching Oprah.
The drawback to a transcervical insemination is you don't get a chance to evaluate the uterus. In a surgical insemination, I have the uterus in my hand. I can feel for cysts, I can visualize where to put the semen. In many cases, by breaking down cysts, I can take conception rates from zero percent to 100 percent.
Using fresh semen in a young bitch is still a regular vaginal AI. Compromised semen which is either poor quality semen, fresh cooled semen, or frozen semen, in a young bitch, should be transcervical insemination. Using poor quality semen in a bitch 4 and a half to five years or older, you want to do a surgical insemination so the uterus can be evaluated.
A surgical insemination is always your greatest chance of having puppies.
Question: Do we need to spin down the semen for a transcervical insemination?
DrHutch: Since the uterus only holds less than a teaspoon, we will oftentimes centrifuge the semen so that the whole volume will stay in the uterus rather than running out through the cervix.
Because the cervix is open in a bitch in season, bacteria can go back and forth into the uterus, so the transcervical insemination does NOT introduce more bacteria than normal into the uterus, no matter which insemination is used, including natural.
Conception occurs from all of these in the same place, the Fallopian tubes, so the method of insemination does not alter the location of the puppies in the uterus, the lack of ease of delivery, or positioning of the puppies.
Question: What part of the ejaculate is the semen in?
DrHutch: The male ejaculates in three distinct fractions. The first fraction just cleans the pipes. The second fraction contains the sperm; that's the part that should look milky and thick. You stop collecting when you see the prostatic fluid, which looks like water. Volume is not important; no one has a trophy for collecting a quart of dog semen.
Question: How is a surgical AI done?
DrHutch: A surgical insemination is a minor procedure that is done under an anesthetic. I use propofol and sevothane, the same anesthetics we use for c-sections, for our surgical Ais. The procedure lasts approximately ten minutes. I make an incision into the abdomen, like a mini mini spay incision - unless I sneeze, then it gets bigger - then I isolate the uterus in my hand. The semen is injected into the uterus using a 22 guage needle, the same size needle used for vaccine. This will not negatively impact future breedings.
It is SO COOL because I can see the uterus fill with the semen; it's like watching the Discovery Channel.
I put in three stiches, five staples, the whole procedure from the time she walks in the door is less than an hour.
Question: How long does frozen semen last, stored?
DrHutch: Frozen semen lasts stored, probably forever. It uses minimal energy when it's stored in the liquid nitrogen at minus 322 degrees F. We had a litter recently from semen that had been stored 25 years, it looked just as good as the day it was frozen. It was great to see the sperm swimming around again, happy to be warm!
The way we package our frozen semen is by the number of normal live sperm cells per dose. A dog with a great sperm count may get multiple multiple breedings out of each collection... a dog with lower sperm count may get one. We calculate our dose so that each breeding has a set number of live normal sperm, rather than by volume or by a set number.
Question: When there is a poor semen sample, is there a way to isolate the viable sperm?
DrHutch: We don't worry about the abnormal sperm, other than mathematically eliminating them, because abnormal sperm does not cause abnormal puppies, so there is no reason to eliminate them
Question: Oxytocin (Pit shots).
Can you discuss the proper use of oxytocin injections during whelping? It seems that many breeders use oxytocin early on in the whelping process, when they feel it isn't progressing fast enough.
DrHutch: A puppy in the uterus has only two elements maintaining its oxygenation and life, one being the heartrate of the puppy, two being the blood pressure from mom to the uterus.
The whole goal in whelping is to maintain vital elements. Oxytocin I use in a very specific manner. If you've gone three hours without a puppy, I use one dose of oxytocin. My dose of oxytocin is two units per ten pounds of body weight. Oxytocin is normally 20 units per ml; I never use more than half an ml, no matter how big the bitch is.
I give one injection; if nothing happens, I give a second injection 20 minutes later. If nothing happens, I go to a C-section.
If you get too much oxytocin at a time, you will cause the puppies not to be expelled from the uterus but shrunk wrapped IN the uterus. The two injections of oxytocin actually increase the blood pressure to uterus which is beneficial to the puppies. If we keep giving them, we LOWER the blood pressure to the uterus, which robs the puppies of oxygen.
Using calcium with the oxytocin... now that we can monitor calcium levels in our practice I do not normally give calcium if the bitch is normal, because it causes the heart to slow down. If I need to give calcium I now use Calsorb, an oral gel that is absorbed almost as quickly as injectable. I can give it in small amounts more often, and don't have to worry about the side effects of injected calcium.
To clarify, my standard protocol (with oxytocin) is two injections; if two don't do it, two, four, ten, twenty, is not going to do it. In most cases I keep score by how many live puppies I deliver, not how many C-section
I avoid. I wait three hours from the last puppy.
My signs of dystocia are:
Temp just before labor readjusts back up to normal;
If I have no puppy born in four hours.
That is my definition of primary uterine inertia.
Straining hard for an hour... that is when you would NOT give oxytocin. Longer than three hours between puppies, that's when you DO give oxytocin.
Any black, red, or green discharge before any puppies are delivered indicates placental detachment and needs attention.
Ultrasounds, fetal monitoring devices, are critical to determine fetal well being. The ability to monitor the fetal heart rate is essential with WhelpWise or having an ultrasound.
I have worked and consulted with breeders using WhelpWise; it's ESPECIALLY important if a veterinarian does not have ultrasound, because there is no other way to monitor the whelps and fetal health
Question: What is WhelpWise?
DrHutch: WhelpWise is the sponsor of this event, actually... it is a fetal monitoring service. You can monitor your bitch's labor progression and fetal heart beat at home. They work well with your veterinarian. They are at http://www.whelpwise.com. Thank you Karen! Karen Copely, the owner and founder of WhelpWise.
I believe that we have the right to expect every puppy that our bitch carries; I am not one who believes you get a litter because you expect to throw one away. The ones we work the hardest on, often turn out to be the best!
Question: Is there any reason to suspect ultrasound causes reabsorption of puppies?
DrHutch: Ultrasounding is normally done day 26-28, when the heart starts beating on the puppy, so we can monitor viability as well as pregnancy. Absorption can occur up until around day 37-38.
Now that we are ultrasounding, we are REALIZING that absorption is not uncommon in the bitch, but ultrasound is only diagnosing it, it's not causing it. Just as x-raying a bitch at day 52 does NOT cause cataracts or whatever in the bitch; it gives us a WHALE of a lot of information about how many pups, their size, their positioning , and their health. That is an urban legend.
Absorption is most commonly caused when the uterus is not able to support the placenta and give nutrition to the puppies; genetic problems that stop the puppies from developing; there can be some viral of infectious causes; there have been some toxins identified in large animals more so than in small animals. Trauma probably plays no role, such as palpation or jumping off the porch.
Question: Reliability of progesterone testing?
I have seen the progesterone testing of a bitch to determine ideal breeding times, to be off by as much as three days.....according to my stud dog...and the successful breeding LATER than the test suggested. Care to comment on this???
DrHutch: It is best if one can obtain progesterone numbers, which should not be a problem in this day and age. Progesterone tests are not species specific, so can be run in human labs, dog labs, horse labs.
The biggest mistake people make in running progesterone tests is they stop before the progesterone goes above five nanograms. The day the progesterone goes above five nanograms is the day of ovulation. The whole world revolves around five nanograms.
The fact that we could determine just the initial rise (rise to 2-3 nanograms of progesterone) is a total fallacy. You must confirm ovulation. I start testing around day 6 of the cycle. You need to run your progesterone every 2-3 days.
Question: What is the most reliable in house test?
DrHutch: At this point, I recommend you find an outside lab to give you a number, as opposed to running in house tests; they are not as accurate.
Question: Doesn't the time lag cause a problem?
DrHutch: You should be able to get the results back in 24 hours max. If there IS a time lag problem, check with a human hospital, or if nothing else, overnight them to me! I can have them that same afternoon!
Question: What about the LH surge?
DrHutch: Because the LH test has to be run every day, and LH is species specific, and in most cases even running the LH we still put most faith in the progesterone tests, I do not run the LH except in very, very specific cases. And the bitches appreciate not being BLED every day for 14 days in a row.... the urine LH is not successful.
Question: What about supplementing progesterone?
DrHutch: The bitch's sole source of progesterone is the ovary. She does not switch the source of progesterone to the placenta like the horse or the cat, therefore it is very uncommon for a bitch to lose a litter due to a premature drop in progesterone.
Giving progesterone when it's not needed will cause birth defects in the female puppies.
If we need to supplement progesterone, I use progesterone in oil injections, as they do show up on progesterone tests, which tells us when to give the next dose. There is an oral synthetic progesterone called Regumate which is used on horses. It will not show up on progesterone tests and therefore will not be monitored.
We only need 2 and one half nanograms of progesterone to maintain a pregnancy. Most bitches during a pregnancy have 8-10 times that amount. A bitch dropping from 20 nanograms to 15 nanograms would still have plenty, and you would definitely not supplement.
I only supplement if the bitch drops lower than 5 nanograms and we have longer than 7 days to our anticipated due date
The bitch's due date, 63 days from her ovulation date, the date she went above 5 nanograms progesterone. Breeding date has nothing to do with whelping date It's the OVULATION date. So if you know the day your bitch goes above 5 nanograms, you can set her due date at 63 days from that as her whelping date: set up your whelping box, take the day off work.
Question: After progesterone reaches 5 nanograms, what are the best days for breeding?
DrHutch: The bitch ovulates an immature egg that has to mature for 48 hours before it can be fertilized. The breeding depends on the anticpated life of semen. A natural breeding can be done the day of 5 nanograms, the day after... the life of the semen is going to cover it. The fresh cooled semen should be 48 hours after 5 nanograms. Frozen, we breed 72 hours after 5 nanograms, because frozen semen only lives 12 hours. Slightly later is better than slightly early because you want the egg to be ready to be fertilized.
Question: Dr. Hutchison, are we intervening too much and harming our breeds with all these AIs, surgical inseminations, etc?
DrHutch: I don't believe that ignoring technicological advances, advances our breeding. I believe anything we can do to make breeding successful, like using frozen semen... is good. Anything we can do to improve our dog breeding and have more live, healthy puppies, interventions in safe, healthy manners, can only be a positive.
I think the Cornell study that showed you get more live puppies from a c-section, showed us that intervention can be a benefit by saving those normal puppies who by some reason cannot get through the birthing process.
Being able to go back to breed to frozen semen from a dog from 25 years ago can only be a positive thing, bringing some of those lost traits back into our lines Plus I need to do this, I have a high maintanance wife.
There were so many great questions, but we have just run out of time... we will have more information in a follow up email... but I just love you guys - you ask the best and the greatest questions and I would like to get to each and every one of them.
So many exciting things lie ahead for us dog breeders. Embryo transfer, in-vitro fertilization, frozen ova to name a few. Yet, I always am amazed at the number of people, especially veterinarians, critical of us for wanting to breed our bitches. They blame us for the great pet over-population problems, like breeding uncontrolled, mixed breeds is our goal.
Go forth, improve your breeds, and good luck on your next litter, it may contain the best one ever!!
Thank you, Thank you, Thank you!!! Good night.
PCFFasDog: The Pet Care Forum and Veterinary Information Network thank all of you for attending this event tonight, and hope you enjoyed it. We especially want to thank Dr. Hutch for giving so generously of this time and information, and of course, to thank Veterinary Perinatal Specialties at http://www.whelpwise.com for their sponsorship. This event would not have been possible without them!
Goodnight and thank you again!
DrHutch: Thanks everyone!
Dr. Hutchison gives his permission for dog clubs to reprint this article in their club newsletters or publications provided the following statement is included:
Copyright 2002 by Dr. Robert Hutchison and the Veterinary Information Network, Inc. Used with permission. All rights reserved. Dr. Van Hutchison can be reached at Animal Clinic Northview, Inc., 34910 Center Ridge Rd., North Ridgeville, Ohio 44039; (440) 327-8282.
Date Published: 8/19/2002 1:42:00 PM
http://www.veterinarypartner.com/Content.plx?A=1224
Monday, April 29, 2013
History of the "TRI-Color"......
This is an excerpt from an article by Ed Faron:
The tan point pattern is caused by a recessive gene on the Agouti series gene locus, the following are the alleles (variations) that are definitely known to occur in the American Pit Bull Terrier. There are also a couple of other genes on this same locus, but they are most likely not present in this breed, so we will ignore them in this article to try and keep things simple.
Agouti locus alleles present in the APBT:
(A) Dominant Black: produces a solid color (ie.black, chocolate or blue)
(AY) Dominant Yellow - Produces reds and buckskins
(AT) Tan-Point (recessive)- produces solid color with tan 'points'
A dog needs to inherit two copies of the tan-point gene to be a black & tan. If a pup inherits one copy of the gene and one copy of the dominant yellow gene, which causes a red or buckskin coloration, then the dog will be red or buckskin, not black and tan. If the dog inherits one copy of the tan-point gene and one of the dominant black gene, the result will be a solid black dog. because of the recessive nature of the tan-point gene, it can actually remain hidden in the gene pool for many generations without expressing itself. In the case of our breed (where this is not a common color) this is what often happens, but it is important to realize that when the tan-point pattern does pop up it is not some new color mutation that appeared out of nowhere, but rather the manifestation of a gene that has been present in this breed all throughout the known history of the American Pit Bull Terrier. Though it is impossible to say for sure where the coloration originated, our best guess would be that it came from some sort of terrier blood that was introduced many, many years ago, probably during the early formation of the breed in the British Isles.
Actually, part of the reason the color is uncommon is that there has been a distinct prejudice against it by many people, either because they feel it is not a typical Pit Bull color, or even actually thought it was the result of a mixed breeding. The latter reason shows an ignorance of basic genetic principles, because the gene is recessive, there is no way you could breed a Rottweiler or a Doberman or Manchester Terrier to a Pit Bull and get puppies with the tan-point markings unless the Pit Bull was carrying the tan- point gene too. If in fact the black and tan color was not present in the APBT gene pool, you would have to breed to a dog of another tan-point breed, and then breed two offspring from such a breeding back together to get black & tan dogs, in the first generation you would get no tan-pointed offspring.
The tan point gene does not actually create a black & tan animal, the gene itself does not produce any color but rather a pattern of a solid color with light-colored 'points'. These 'points' always appear in specific places but the actual size and distribution of them is somewhat variable. The exact coloration that is produced by the tan-point gene is dependent on the color genes present at other loci, for instance if the pigmentation is black, the result will be a black & tan, but if the dog's pigmentation is chocolate or blue then the pattern would produce a chocolate & tan or a blue & tan, respectively.
http://www.americanironkennels.com/TriHistory.html
The tan point pattern is caused by a recessive gene on the Agouti series gene locus, the following are the alleles (variations) that are definitely known to occur in the American Pit Bull Terrier. There are also a couple of other genes on this same locus, but they are most likely not present in this breed, so we will ignore them in this article to try and keep things simple.
Agouti locus alleles present in the APBT:
(A) Dominant Black: produces a solid color (ie.black, chocolate or blue)
(AY) Dominant Yellow - Produces reds and buckskins
(AT) Tan-Point (recessive)- produces solid color with tan 'points'
A dog needs to inherit two copies of the tan-point gene to be a black & tan. If a pup inherits one copy of the gene and one copy of the dominant yellow gene, which causes a red or buckskin coloration, then the dog will be red or buckskin, not black and tan. If the dog inherits one copy of the tan-point gene and one of the dominant black gene, the result will be a solid black dog. because of the recessive nature of the tan-point gene, it can actually remain hidden in the gene pool for many generations without expressing itself. In the case of our breed (where this is not a common color) this is what often happens, but it is important to realize that when the tan-point pattern does pop up it is not some new color mutation that appeared out of nowhere, but rather the manifestation of a gene that has been present in this breed all throughout the known history of the American Pit Bull Terrier. Though it is impossible to say for sure where the coloration originated, our best guess would be that it came from some sort of terrier blood that was introduced many, many years ago, probably during the early formation of the breed in the British Isles.
Actually, part of the reason the color is uncommon is that there has been a distinct prejudice against it by many people, either because they feel it is not a typical Pit Bull color, or even actually thought it was the result of a mixed breeding. The latter reason shows an ignorance of basic genetic principles, because the gene is recessive, there is no way you could breed a Rottweiler or a Doberman or Manchester Terrier to a Pit Bull and get puppies with the tan-point markings unless the Pit Bull was carrying the tan- point gene too. If in fact the black and tan color was not present in the APBT gene pool, you would have to breed to a dog of another tan-point breed, and then breed two offspring from such a breeding back together to get black & tan dogs, in the first generation you would get no tan-pointed offspring.
The tan point gene does not actually create a black & tan animal, the gene itself does not produce any color but rather a pattern of a solid color with light-colored 'points'. These 'points' always appear in specific places but the actual size and distribution of them is somewhat variable. The exact coloration that is produced by the tan-point gene is dependent on the color genes present at other loci, for instance if the pigmentation is black, the result will be a black & tan, but if the dog's pigmentation is chocolate or blue then the pattern would produce a chocolate & tan or a blue & tan, respectively.
http://www.americanironkennels.com/TriHistory.html
KING CAIN x AYE BAY BAY................
This will be the pedigree for our next litter of American Bullies....
http://www.bullypedia.net/americanbully/testmating.php?dam=171454&sire=105203#.UX7uahf1XgQ.facebook
http://www.bullypedia.net/americanbully/testmating.php?dam=171454&sire=105203#.UX7uahf1XgQ.facebook
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