POULTRY IMMUNOGENETICS - WHICH WAY DO WE GO

A major goal in poultry immunogenetics is the enhancement of innate im munoresponsiveness and resistance to disease. This may be pursued by s tudying either single genes or polygenic traits. The MHC is perhaps th e best-characterized family of host genes that modulates response to a variety of antigens and pathogenic challenges. The association of dif ferent MHC alleles with disease resistance has been known for decades. But only recently has analysis at the DNA level opened new avenues of understanding and new opportunities for application of genetic variat ion in the MHC with immunoresponsiveness. An alternate approach to mol ecular analysis is selection for a desired phenotype controlled by pol ygenes. Several studies have illustrated the successful alteration of immunoresponsiveness by genetic selection for antibody production. Rec ently, a selection program based upon multiple traits of immune respon se was conducted. Results of this project demonstrated that selection on multiple immune-response traits altered immunophysiology, MHC allel ic frequencies, and disease resistance. Several areas for future pursu its in poultry immunogenetics research are proposed.