Submitted to: World Congress of Genetics Applied in Livestock Production
Publication Type: Book / Chapter
Publication Acceptance Date: May 4, 1994
Publication Date: N/A
Interpretive Summary: This review is for an international meeting on "Genetics as applied to livestock production." It introduces the reader to the genes of the major histocompatibility complex (MHC). This set of genes is found in all domestic animal species and is very important in determining how an animal will respond to vaccines and to infections. For livestock producers, therefore, it may be advantageous to know whether individuals, who have inherited specific genetic versions (alleles) at one of these genes, will then be more resistant to certain infections or will be more responsive to a new vaccine. This review cites the most recent work in this area for cattle, sheep, swine, horses and chickens. It explains how this basic information will help researchers help producers to identify the best breeding animals and to prevent certain diseases in their livestock though genetic selection.
This review highlights the recent advances in our knowledge of the major histocompatibility complex (MHC) of livestock and of the potential impact of specific alleles of genes within this complex on animal disease resistance and vaccine responses. Because of the extensive research in this area, this review presents only newer data, i.e., that published after 1990. We first comment on the importance of the MHC and the many genetic loci that they encode on immune responses, and then summarize the current knowledge of the MHC of 3 major domestic animal species: chickens, swine and cattle. The rationale for animal disease studies that attempt to identify both resistant and susceptible individuals is compared to the focus of human disease studies that mainly trace susceptible individuals. Recent results are presented of studies aimed at identifying animals with specific MHC alleles, which make them more resistant or susceptible to specific infectious diseases, or which enable them to be more responsive to vaccination. Finally, the future of these studies, and of alternate approaches involving in vitro testing protocols, are discussed.