Thursday, December 4, 2008

Genetic diversity

The issue of genetic diversity is getting more attention from the research community. As the industry pursues its goal of creating the most efficient organism to convert feed into meat and eggs, the genome of the birds being raised is being ever more restricted. Limited genetics means limited ability to respond to environmental conditions, an inherent weakness even as birds meet the industrial goal of growing bigger faster.

"This means most of the world's chickens lack characteristics that evolved when they lived in the wild, and may be useful again to help them face stress and disease as livestock," writes Debora MacKenzie in New Scientist, Chicken Genome Plucked Bare by Inbreeding, November 4, 2008

A study from The Netherlands offers the concept of 'robustness,' individual traits of an animal that are relevant for health and welfare, into selective breeding programs. [Clearly, this applies to industrial programs, as small flock breeders, especially those focusing on traditional breeds, typically value vigor and vitality and wouldn't consider including birds in their breeding pens that are not healthy and robust.]

"In order to be ethically acceptable, selective breeding in animal production should accept robustness as a breeding goal," the authors write in their abstract to A Plea to Implement Robustness into a Breeding Goal: Poultry as an Example, Journal of Agricultural and Environmental Ethics, L. Star and E. D. Ellen, April, 2008 .
No one would question the robustness of this Russian Orloff, belonging to Michelle Conrad.

Another international research team has come to a similar conclusion,, which attracted the attention of the NYTimes Nov. 3, 2008:

"We suggest interbreeding some experimental commercial poultry lines with native or standard breeds as a backup plan, or ace in the hole, to help the industry meet future challenges, as traits such as disease resistance may be found among the rare alleles of other birds," said Bill Muir, Purdue University animal sciences professor who participated in the research.
Recognition of the importance in the commercial poultry community would help focus attention on preserving them. This attention is welcome and long overdue.


Amy - "Twelve Acres" said...

It's a relief to see an intelligent approach to breeding for a change. I think it's very important to select for good health, vigor and vitality. A friend of mine raised some white commercial turkeys this year and his toms died of heart attacks when they got 30+ pounds! I want my birds to be tough and able to reproduce on their own.

cbarown said...

As part of being able to increase diversity, we need to maintain healthy populations of as many different heritage breeds as possible. The American Livestock Breed Conservancy maintains a list of threatened poultry species as does The Society for the Preservation of Poultry Antiquities. While we breed to make our stock better, we can't neglect the original sources of these genetics.