By D.P. Sponenberg – Breeds are important for many reasons. A main contribution of breeds is to organize the variation in a species into different genetic packages so that owners can choose the specific combination that works best for them. For example, Icelandic chickens and Egyptian Fayoumis are each going to perform best in different environments, and if breeders do not take good care of these genetic packages, then future generations will simply not have some of the options that have blessed the current owners.
Why does all this matter? Breeds matter, because each one of them is a genetic package that can be used for some combination of purposes in some specific range of settings. It is important to keep that in mind, and to not squander those packages by mixing them all up. They are more than pretty birds or pretty animals — each one served some human community as they survived in a specific setting. That is the true importance of breeds, and without them we wouldn’t be here today to even have the discussion!
Breeders of poultry and breeders of mammalian livestock often are thinking different things when they think “breed.” Exploring these differences can help to facilitate communication, and can also help to advance effective breed conservation. For this discussion, “poultry” will mean avian breeds, and “livestock” will mean mammalian breeds, even though these are hardly ideal definitions all the way around. While breeders of each of these have specific major ways they think about breeds, the overlap is so great that no single broad-brush approach will easily capture all the details.
Breeders of both poultry and livestock breeds do agree that the basic characteristic of breeds is their consistent appearance and performance. That is, one breed is usually told from another because it has an array of physical traits that are repeatable and unique to that breed. This uniformity comes down to the present in different ways, and these differences are where breeders of poultry and livestock have often diverged. Some important and cautionary examples where the attitudes overlap between these two big classes of breeds can help tease out some important lessons.
In the minds of most livestock breeders, the uniformity of breeds results from the expected interactions of foundation (what goes into the original mix), isolation (so the mix is not further jumbled or changed along the way by outside stock), and selection (which specific animals breeders choose to keep, and which they choose to reject). In most cases, a fourth dimension is piled on here, which is that the whole result is functioning in a specific environment, along with people, for the purposes of production. These are the four most important aspects of a functional breed.
This whole process of breed formation tends to yield a final appearance almost as a secondary result. The cascade of events starts with foundation (what was available), then isolation (nothing else was available!), and selection (breeders needed the animals to do this or that) and the result was animals shaped by the interactions of these three in the environment and serving people. This process always results in a certain degree of uniformity, both for appearance and production. The end of that process is an easily recognizable breed, and most observers forget all those steps that went into the process, and concentrate only on the final relatively uniform result.
Breed uniformity can then be taken a final step as a more deliberate process when breeders organize, notice the similarities among their animals, and then deliberately eliminate some rare variants that do not fit the majority package of traits. This final step is breed standardization. Importantly, in most cases the standardization was the crowning final event in a process already well in progress, and leading to the end result of reasonable uniformity. This last step gives the amazing uniformity across an entire breed that makes it so easily recognizable.
For several poultry breeds, this same process of breed development has occurred, resulting in breeds that function biologically in exactly the same way that livestock breeds function. These can be called “primary” breeds because they follow the usual trajectory of foundation, isolation, and selection leading to a uniform and recognizable bunch of animals or birds that are designated “breeds.”
However, for many breeds of poultry, and some of mammals, a second pathway has become nearly as important as this first, and often poultry breeders do not reliably distinguish between these two pathways in either their thinking or their practices.
Poultry breeders, seeing the almost inadvertent uniformity brought by the process described above, have often targeted superficial phenotypic uniformity without necessarily including the steps of foundation, isolation, and selection. Poultry breeders have often envisioned a final external appearance, and then have blended various influences to attain that overall product. In many poultry breeds, the result has been that varieties within the breeds do not share common histories of foundation, isolation, and selection with one another. For example, White, Buff, and Partridge Chantecler chickens each come from different foundations, even though the final products resemble one another externally in all but color. Selection is the key here, with foundation and isolation playing minor roles, if any at all.
This second path to breed development, especially in poultry, leads to a logical split in what might be called primary breeds as opposed to secondary breeds. Primary breeds are those with birds that have a shared background of foundation, isolation, and selection. Secondary breeds lack this shared background and end up with their uniformity coming from targeted selection for a specific phenotype, even though the foundation and isolation steps are not shared all that widely among members of the breed. Both primary and secondary breeds have importance, but they are fundamentally different in their function as biological units. As with most of life, a few fall in between these extremes, and these include some old breeds that came from blending primary breeds together long ago.
The issues that spring from primary and secondary breeds are important and glaringly obvious for poultry, but are no less important for breeds in nearly every species where breeders have resorted to crossing to other breeds for performance gains, or in order to have a competitive edge in the show ring or other evaluations. This leads to “secondary breeds,” whether in birds or in mammals, with the same consequences for the underlying genetic resource that a breed should ideally be. Horses have many breeds where this has been the case (show-type Morgans, and many others).
Many poultry breeders consider outward uniformity to be all that there is to breeds. In that case, outcrossing to bring things into a breed is perfectly logical because the breed is indeed (in their minds) that final external package, and any way to get that is a legitimate breeding practice.
These outcrosses do change the underlying genetic package of the breed, which is of conservation importance. A good example is the multitude of Wyandotte varieties.
Some, like the Silver Laced, White, and Black, do indeed share a common foundation, isolation, and selection history. Others, like Golden Laced, Buff, Partridge, Silver Pencilled, Columbian, Blue Laced Red, and Blue, do not share that background. All of them do share an array of skin color, comb type, and body shape. The superficial similarities are a veneer over very real underlying genetic differences between the varieties of this one breed.
Some of this comes from standards that emphasize external form as well as color. An interesting example of how this can affect breeds is the Java, which has Black, Mottled, and White varieties. All of these go back to the same foundation, making the Java an old, primary breed. Of late, some reddish birds popped out of different bloodlines, and these have led to the “auburn” variety with the same foundation of the old primary breed that the other varieties belong to. As with many new developments in old breeds, though, the tendency is to insist that all auburns end up with the same repeatable color, so some of these interesting variants are doomed to be discarded, because ultimately only one single pattern will be crowned “auburn,” and the others, from the same old breed, may well be deemed illegitimate.
The focus on external form has other consequences, and unfortunately can lead to the “secondary breed” attitude and the practices that go along with it. These can put at risk the many poultry breeds that are indeed primary breeds. These genetic packages must be protected, and must be bred pure within the breed in order to assure survival of that genetic package. In these primary breeds, specific genetic combinations are important, and outcrossing can easily disrupt these.
Poultry breeders need to be diligent in understanding the character of their breeds, and need to reflect on the importance of foundation and isolation in maintaining the genetic uniqueness of their breeds.
Ignoring this and resorting to outcrosses can assure that the result is “such and such” a breed in name only, with the underlying genetic package based on foundation and isolation long gone.
Importantly, no species has been completely exempt from this confusion and genetic mismanagement. For breed conservation to be genetically meaningful, the breeds involved have to be true genetic resources, and breeds that have been crossbred or heavily contaminated by outside breeding simply do not qualify by that criterion. Sorting through the details of breed history (both the written and the unwritten versions!) can be a tricky undertaking, but is essential if pure breeds are to be stewarded for effective conservation. To do that, it is important to understand that “breed” may mean two different things to two different people.
D. Phillip Sponenberg, DVM, PhD, professor of pathology and genetics at the Virginia-Maryland Regional College of Veterinary Medicine, is Technical Advisor for the Livestock Conservancy.
Thanks to Christine Heinrichs for editing and photos. She is the author of How to Raise Chickens and How to Raise Poultry, published by Voyageur Press. Both focus on raising traditional breeds in small flocks.
CATEGORIES OF BREEDS
PRIMARY, OLD FOUNDATION
• Black Sumatra
• Old English Game
• Sebright Bantam
• Sicilian Buttercup
• Silky Bantam
• Wyandotte (silver laced, white, black)
• Jersey Giant
• Plymouth Rock other than Barred
• Rhode Island White
• Wyandotte (golden laced, buff, partridge, silver penciled, columbian, blue)
OLD BREEDS FROM A BLEND OF PRIMARY BREEDS
• Barred Plymouth Rock
• Modern Game
• New Hampshire
• Rhode Island Red
Originally published in the February/March 2014 issue of Backyard Poultry.