Genetic and epigenetic regulation of the bovine immune system : practical implications of the high immune response technology

Identifying dairy cows with superior immune response (IR) reduces disease, increases farm profit, improves milk quality and increases animal well-being. In Canada, it costs the dairy producer $110 to $320 per case of mastitis, and it has been estimated that almost 1 out of every 5 dairy quarters in Canada is infected with a mastitis-causing pathogen (Canadian Bovine Mastitis Research Network, “What’s New in the World of Mastitis Research?” http://www.medvet.umontreal.ca/rcrmb/dynamiques/PDF_AN/Results/NewspaperWhatsNew.pd f. 2009). The emergence of antibiotic resistant pathogens is of increasing concern to the producer, as well as to the public. Around the globe there is a concerted effort to limit the use of antibiotics, particularly in food-producing livestock. Therefore, in keeping with the European Unions’ proactive thinking that “prevention is better than cure”, alternative methods for disease control are earnestly being sought for animal agriculture. Various genetic approaches are being evaluated as suitable methods to enhance disease resistance of livestock. One of the most attractive options available is to make use of the animal’s own immune response genes to select for healthier animals with naturally superior immunity. This approach can work well on both conventional and organic dairy farms. This immunogenetic approach will be the focus of this article.