Animal breeders have no qualms directing intensive systems of artificial selection.
Eugenics is defined with reference to humans, as any consideration or implementation of artificial selection. There is little doubt that it would be effective, but there is some disagreement about what an "improvement" would represent. We are not cattle to be bred to specification, but organisms with dignity and freedom- specifically freedom from meddling by others in our reproduction. Wild animals have this freedom as well, by default. But domestic animals- that is a different story. For all our "humane" societies and pampering of some, our treatment of others is distinctly undignified. And that includes their breeding.
Across the domestic animals, from racing horses and show dogs to dairy cows and chickens, breeding these days is carried on at unprecedented intensity, with the most advanced scientific and statistical techniques. For farm animals, this has led to inbreeding and alarming malformations, such as chickens that can't walk, and cows with chronic udder infections. For dogs, the creation of fundamentally malformed breeds also leads to chronic suffering, (short snouts, short legs), as does lack of care in breeding for temperamental health.
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| These animals have serious problems, of a genetic nature. |
Animal breeding has progressed through three major stages. First is the traditional approach, using hunches and personal judgements- using the best animals, and perhaps cross-breeding with animals from other farms to retain diversity, if any directed breeding is done at all. With a relaxed approach, this led to generally good results, establishing the great dog breeds and other livestock, where hardiness and health were always prominent values. But in pigeon, cat, dog, and other casual breeding since Victorian times, amateur breeding like this can also go rather astray.
In modern livestock breeding, this was superseded by the use of Estimated Breeding Value, or EBV, which is a systematized way to account for the genetic, rather than phenotypic trait quality in animals, by accounting for their relatives, as far as they have been measured, and also by accounting for uncertainties around heritability and systematic and environmental effects on the trait of interest. This concept puts breeding on a far more scientific basis, with quantification of traits, and of pedigrees. One result is that the breeding value can be estimated for animals who do not even have the trait, such as male dairy cattle. Another has been that animal breeding has been even more relentlessly driven to meet commercial and consumer objectives, even ones that shift over time as tastes change.
Naturally, the EBV method has now been supplemented by DNA-based evaluations in more recent times. The ability to "see" into the genome by sequencing some or all of it, thereby establishing a landmark map based on variants distributed throughout, allows the traits (if linked to such landmarks) to be tracked in all individuals, regardless of phenotype, and even in individual gametes and fetuses. This dramatically reduces the lottery that otherwise is genetics. However, its value is significantly bounded by the fact that most interesting and desirable traits are usually not genetically simple (like, say, eye color), but are complex, influenced in very small amounts by many different loci / genes.
This is a frontier for animal rights and humane policy development, that animals not only should be treated well, but bred well. In livestock breeding, European countries have some relatively aspirational standards and laws, the US lacks even that. The "standards" used by such organizations are the American Kennel Club are worse than nothing, as they drive breeding for looks alone, and welcome the most obscure and unhealthy breeds, regardless of grave malformations, temperamental disasters, and inbreeding. While health of the animal needs to be paramount, other issues such as the ability of animals to live without special care and infrastructure, and genetic diversity, also need to be addressed, if we are going to be serious stewards of animals in our care.
