Heritage livestock breeds are often a good choice for small farms and homesteads, due to their adaptability and hardiness. However, the fact that they have fallen out of favor means that their numbers are often small. In an effort to build up a breed, without too much in-breeding, some associations will allow a process called “breeding up.” Purebred males are bred to crossbred females to gradually create a population of new purebred off-spring over multiple generations.
So, how does it work? It starts with a population of foundation females. These are usually selected to be closely related to the target breed, or at least possessed of a characteristic that is important in the target breed. These females are bred to purebred males from the target breed.
The best of the daughters of these crosses are kept, and they are now 50% the target breed. The half-breed females are then bred back to purebred sires. And the new generation of daughters are 75% purebred. The next generation is 87% pure, the fourth generation is 94% pure, and the fifth is 97% purebred.
At this point, these F5 generation animals are usually allowed to be registered as purebred. Some registries will indicate an animal that was admitted via a breeding up program with an asterisk.
Improving Genetic Diversity
The Dutch Belted cattle breed, for example, is quite rare in the United States. Many of the cattle that are registered are scattered about in small herds. Breeding by artificial insemination allows owners of a small number of cows to be able to breed to a purebred bull, without having to locate a bull nearby. But the pool of available animals is still very small. So the breed association allows breeding up.
The website for the Dutch Belted Cattle Association details the procedure. Beginning with a grade or registered cow of another breed of dairy cow, each resulting daughter is identified with a 0.5 Dutch Belted Cattle Certificate. When this daughter is bred back to a pure Dutch Belted bull, any resulting daughter can be issued a 0.75 Dutch Belted certificate.
This continues as the percentage increases. After the resulting daughter is 0.9375 Dutch Belted, she is eligible for registration. This isn’t automatic, however. She must meet color and conformation guidelines, and produce at least 11,000 pounds of milk within a 365 day lactation cycle. If she meets all these criteria, her progeny (male or female) can then be registered as purebred individuals.
You might have noticed that only daughters are part of this process. That has to do with the simple fact that a cow can only have one calf (well, twins are possible, but not really all that desirable) per year. Whereas a bull can produce many offspring, especially via artificial insemination. All this means that breeding a purebred Dutch Belted cow to another breed of bull does nothing to increase breed numbers, when she could easily have produced a purebred calf instead.
If you’re sharp-eyed, you might also have noticed that the rules for the Dutch Belted program specifies that the original cow must be from a dairy breed. This is because genetics on paper and genetics in actual animals are two different things.
While a cow that is 93.75% Dutch Belted may carry a large proportion of genetics from that breed, the maternal influence on the conformation, milk production, and other traits will be stronger than the math would imply. In fact, I’d be very much surprised if you would end up with an F5 cow that could produce 11,000 pounds per year if you started with a grade beef cow.
Importing a Unique Breed
That’s why some breeding-up programs will even specify which maternal breeds are acceptable as foundation animals to begin a breeding-up line. The Valais Blacknose sheep, billed as “the world’s cutest sheep,” originated in Switzerland and until recently was found only in Europe. Due to diseases like scrapie, importation of live sheep or even live embryos is currently prohibited. Semen can be imported, however, and so a breeding-up program started to bring them to the United States.
The Valais Blacknose Sheep Society maintains records for the program. Their committee recommends that Scottish Blackface sheep be used as the foundation breed, with Lincolns or Leicester Longwools considered acceptable as well.
Why? Experience with different crosses has indicated that the maternal effects from those breeds result in offspring that most closely meet the breed standard. The Valais Blacknose has quite a distinct color pattern: helical horns, and a longer staples, looser crimped fleece. The recommended maternal foundation breeds make the chances that F5 offspring meet the breed standard much higher.
It should also be noted that a breed that is entirely imported in this manner will always differ somewhat from the original breed in Switzerland. But careful selection should allow the Society to establish something awfully close.
Declaring the Success of a Program
BecauseB The Dales Pony, for instance, teetered on the edge of extinction after World War II. In an effort to save the breed, unregistered animals of the right type were brought in. And at one point, three Fell pony stallions were used on Dales mares to help achieve a sustainable population. By 1971, the program was deemed a success and it was discontinued. The association now only permits registration of purebred animals.
If you have a love for a very rare breed, time, patience, and the resources to follow program guidelines, you might find helping to build up that breed by breeding up new animals a fulfilling endeavor.
Holly Stockley is a veterinarian and heritage-breed genetic biodiversity steward in Western Michigan, where she and her husband are restoring 10 acres of neglected land that includes a walnut plantation. She participates in the Lost Apple Project – Midwest and has started a small orchard of heritage apple varieties, teaching herself to graft. Find Holly at BrambleberryMeadow.com and listed to her Vintage Americana Podcast. Connect with her on Instagram @brambleberrymeadow and @vintageamericanapodcast.
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