The more I work with chickens and goats (and dogs for that matter), the more convinced I am that the designation “purebred” for animals is not only useless but harmful, and that livestock shows, in which animals are judged for conformation rather than production, are a poison to agriculture.
There’s certainly a case to be made in favor of purebreds, in that they can be very predictable in terms of appearance, behavior, and important measures like feed conversion (the amount of food an animal needs to produce milk, eggs, meat, wool, or some combination thereof). But the downside is that limiting the gene pool artificially is actively harmful to populations.
In goats, we’re starting to see a problem in Nubians because of the G6S mutation, a recessive that can cause a goat to fail to thrive and then drop dead suddenly at quite a young age. Scientists estimate that 25% of the population of Nubians has it, and so far not nearly enough breeders are testing for G6S status on their Nuban herds, which means it can pop up unexpectedly. For the small breeder for whom each animal is a friend and pet as well as milk producer, the emotional impact can be terrible. For commercial dairies, it can represent a serious loss of income to have doelings start dropping dead.
Among chickens, you see formerly productive breeds that are no just feathery lawn ornaments. The Buckeye, for instance, was bred to be a thrifty, hardy free-range bird that required minimal human input to put meat and eggs on the table. Extensive breeding has made it a bird that is more comfortable sitting in coops eating pellets from a feeder rather than a wily hunter of bugs and seeds. When I went looking for a free-range Buckeye flock to try and bring some actually useful Buckeye genetics in, I couldn’t find a single one within range of me, and there were perishing few nationwide.
The popularization of the incubator, brooders, and wide availability of pelleted feed, along with the growing crop of people who just want a couple hens for the back yard, means that the chickens our great-great-grandparents knew are hard to find. Incubators allow every single egg to hatch, even those that produce weak chicks who need coddling in a brooder. Likewise the coddling in a brooder allows chicks to live that don’t have the physiology to handle local weather conditions, diseases, and parasites. These chicks grow up to be the chickens who need constant deworming, climate-controlled coops, and other interventions to survive. Which is all very good and well if you want a couple hens for your backyards while relaxing on your Blue Oak Patio Furniture. When you want meat and eggs for your table that sort of chicken is not terribly useful.
Meanwhile, people like to pay premium prices for “purebred”, show-quality chickens, or even just purebred rare chickens. Often these birds are the product of extremely limited gene pools. While some people will assert with a straight face that inbreeding does not affect chickens, they are either lying because they want to sell you poultry or they’re woefully ignorant. Loss of genetic diversity will get you chickens who fail to thrive, drop dead mysteriously and unexpectedly, who have poor feed conversion rates, and who are so damn stupid they won’t even come in out of the rain (nota bene: show quality silkies are NOTORIOUS for this).
Part of the problem, a big part of the problem, is that people are raising livestock for pets these days. Our ancestors avoided the pitfalls of inbreeding by ruthlessly culling any animal who didn’t perform and putting it on the dinner table. Today’s “homesteaders” are often unwilling to cull this hard, and that goes triple for people who are hoping to cash in on the craze for expensive rare breed livestock.
And therein lies the rub. While it’s important to preserve these reservoirs of genetic diversity, it’s equally important that they not be degraded into uselessness by a refusal to cull animals that don’t perform by removing them from the gene pool one way or another. Otherwise we just wind up with more sad fat Buckeye chickens sitting in cages at shows, unable to fulfill the promise of their ancestors.