Using short term or dual career breeding stock can greatly benefit a working dog’s breeding program via selective breeding, allowing for quicker generational turnover, and keeping a good effective population size.
Selective breeding is the practice of mating individuals with desired traits as a means of increasing the frequency of those traits in a population. In selective breeding, the breeder attempts to isolate and propagate the genotypes (genetic constitutions) that are responsible for a dog’s desired qualities in a suitable environment.
Generational turnover is defined as the length of time from one generation of animals to the next generation.
By using short term/dual career breeding stock, you can utilize the advantages of selective breeding aka altering gene frequencies in the population by accelerating generational turnover.
For example, you decide to work on the prevalence of hip dysplasia. As we know, controlling the prevalence of inherited disorders constitutes an important issue for the health and welfare of pedigree dogs. The use of sires with high genetic merit has been viewed as a promising breeding strategy to improve the health and welfare of dogs (Wilson and Wade, 2012, Fikse et al., 2013). Selection after the evaluation of estimated breeding values (EBVs) is the most effective way to genetically improve hip joint status. By using a short-term stud, you can select the stud with the highest genetic merit, neuter, and send him back into training. His offspring can then be evaluated, and breeder candidates can be picked from who has the highest genetic merit. Repeat the process. Thus, you improved each generation quickly. This also allows for good practices when it comes to resource management as the studs can be sent back into training and potentially graduate from your program.
Additionally, short term or dual career breeders allow a breeding colony to maintain an effective population size by utilizing a larger number of breeders. Effective population size (Ne) is a key parameter in population genetics. It is the number of individuals that effectively participate in producing the next generation. It also quantifies the magnitude of genetic drift and inbreeding within a breeding colony. The overall goal is to have Ne be as high as possible. For example, a colony could depend entirely on short term or dual career stud dogs, giving them 2 to 7 different studs to use each year vs a colony that utilizes the same 7 studs over a 5 year period. The scheme using short term studs will give a colony a larger Ne.
As to the practicalities of a short term or dual career breeders, we’ll hear from several programs currently utilizing the practice.
Do you use both males and females for short term careers?
“Currently, we do not use females in short term careers. However, we do like to prove their fertility as soon as possible by breeding them on the first heat after they complete their medical clearances. If we determine a fertility issue or encounter something as dramatic as an irreparable uterine tear during a c-section, we will consider them eligible to go into training, although this is very rare. We frequently use males as “dual purpose” dogs (not exactly “short term”) and we do that through the use of frozen semen primarily. Because we have the in-house cryobank, any male breeder candidate has their semen banked during the medical screening process. If a medical clearance issue surfaces, we can easily discard his semen, neuter and return him to training. If there are no medical issues, we then have to decide whether we will keep him as an active intact member of the breeding colony or make him a dual purpose dog. For our organization’s size, our hope is that each active stud will sire 8-10 litters during their career. Dual purpose dogs are those that are unlikely to sire that many litters, based on their EBVs, temperament & pedigree. Dual purpose males usually graduate as working guide dogs well before we opt to use their frozen semen to sire future litters, but occasionally they will sire a litter just prior to being neutered if an appropriate mate comes into heat.”—Clover Williams, Guiding Eyes for the Blind
“We use both males and females in a short-term breeding scheme. All of the males after their breeding career, which usually last around 3 to 6 months, are placed back into training after neuter. We will typically breed our females for a full career but some females that we have identified as being useful for production or making advancements in genetic merit, but who we don’t want a full career with are bred for one litter, spayed, and placed back into training. The reasons we wouldn’t breed a female for a full career are: she has siblings or half siblings in the colony, we’re trying to quickly move onto the next generation, or her family has a history of reproductive issues.” –Allison Peltier, Freedom Service Dogs
What are the benefits of short term breeders?
“Through the use of frozen semen, we can capitalize on the genetic merit of many more studs, while also allowing us to service our client base efficiently. Frozen semen also allow us to wait for the most ideal mate rather than the limited brood options before he needs to be neutered.”—Clover Williams, Guiding Eyes for the Blind
“We can selectively breed against certain traits like hip dysplasia or body sensitivity that we found in our foundation stock and have faster generational turnover. This practice allowed us to improve our success rates and meet the needs of our clients.” –Allison Peltier, Freedom Service Dogs
Is the cost of clearancing out a dog worth it for a shorter breeding career?
“In our scheme, it definitely is. We screen 8-10 breeder candidates monthly, which allow us to approach specialists for quantity discounts while counting on our own veterinary staff to do the basics, both of which drive our costs down. We frequently screen two brothers with the plan to only keep one intact, but that brother’s frozen semen helps with genetic diversity and our effective population size. Since our active breeders do not receive formal training, the insight the trainers provide on the dual career dog & the sibling’s trainability is of great value, including capturing additional BCL data. We are fortunate to be able to bank semen inexpensively while assuring good conception rates when we use the semen.” –Clover Williams, Guiding Eyes for the Blind
“Most definitely. Since all our studs are being used within 3 to 6 months, frozen, and sent back into training, we are still getting the most out of the resources. With our females, we will get a litter and then hopefully a graduate as well. The cost of maintaining a semen bank at a local vet clinic is worth the expense to give the studs a dual career.” –Allison Peltier, Freedom Service Dogs
Does breeding affect trainability?
“All dogs are neutered before entering our training process and we have not found significant negatives associated with the fact that he has been collected or bred once that hormonal component has been removed.” –Clover Williams, Guiding Eyes for the Blind
“Our colony is newer, started three years ago. Because of that, stud use is short term and then they are placed back in training. We will freeze our studs to breed in the future and sometimes will also be able use them for live cover. We can best utilize our resources and put selection pressure against some of the traits we’d like to move from away quickly by short term usage. We also have success in breeding some of our females for a litter, spaying, putting back them into training, and then having them graduate to serve a client. Again, it’s using our resources to the fullest while making the best decisions for operations.”—Allison Peltier, Freedom Service Dogs
Article by Rachel Goldammer, with many thanks to Guiding Eyes for the Blind and Freedom Service Dogs for their contributions.
References
- Wilson, Bethany & Wade, Claire. (2011). Empowering international canine inherited disorder management. Mammalian genome : official journal of the International Mammalian Genome Society. 23. 195-202. 10.1007/s00335-011-9366-y.
- McGreevy, P., & Nicholas, F. (1999). Some Practical Solutions to Welfare Problems in Dog Breeding. Animal Welfare, 8(4), 329-341. doi:10.1017/S0962728600021965.
- Wang, E. Strandberg, Å. Viklund, J.J. Windig, S. Malm, T. Lewis, D. Laloë, G. Leroy, Genetic improvement of canine hip dysplasia through sire selection across countries, The Veterinary Journal, Volume 248, 2019, Pages 18-24, ISSN 1090-0233, (https://www.sciencedirect.com/science/article/pii/S1090023318306026).
- W.F. Fikse, S. Malm, T.W. Lewis, Opportunities for international collaboration in dog breeding from the sharing of pedigree and health data, The Veterinary Journal, Volume 197, Issue 3, 2013, Pages 873-875, ISSN 1090-0233, https://www.sciencedirect.com/science/article/pii/S1090023313001974.
- International Working Dog Registry Knowledge Database. (2023, March 30) Effective population size, International Working Dog Registry. https://www.iwdr.org/master-knowledge-base/effective-population-size/
- Peltier, Allison and Goldammer, Rachel. Building a Purpose Bred Breeding Program. IWDC Oct, 2023. www.iwdba.org. Powerpoint Presentation.
- International Working Dog Registry Knowledge Database. (2022, September 23). Genetic diversity – managing inbreeding. International Working Dog Registry. https://www.iwdr.org/master-knowledge-base/genetic-diversity-managing-inbreeding/