As every dairy farmer knows already, the disease incidence in dairy cattle is on the rise. Farmers generally deal with the problem through various management practices and costly aid from veterinarians but these efforts appear to be ineffectual in slowing the number and severity of occurrences. However, there may be a way to turn this situation around and cut treatment costs too via a new genetic technology, called High Immune Response (HIR).
Essentially the technology is a testing procedure and management tool to identify animals with high immune response traits; breeding High Immune Responder individuals then leads to the pronouncement of the traits and thus healthier offspring that tend to stay healthy. In addition, trials show that these animals respond better to vaccines and produce higher quality colostrum.
Many benefits are touted by the developers and by Semex, which has exclusive rights to the technology for the next decade, including lower vet bills and higher production. The conservative estimates of the financial benefit of a High Immune Responder cow versus a Low Immune Responder cow is $124 a year. HIR also has appeal as a natural alternative to widespread antibiotic use in livestock – an issue of heightened interest given increasing regulations worldwide to stem routine antibiotic use.
Research conducted in the U.S. on some 700 cows found that HIR curbed mastitis by 27%, and that one group of HIR cows had no cases of mastitis after 220 days and counting in milk. It also found a 17% reduction in metritis and 32% reduction in retained placenta incidents. Other studies found as much as 50% reduction in diseases.
Professor Bonnie Mallard in the Department of Pathobiology at the University of Guelph in Ontario is the scientist behind the development of HIR. She spoke this month at the 2013 SEMEX Dairy Conference saying that HIR could reduce disease by as much as 4% to 8%, and reduce treatment costs by £50 per cow per generation. According to Farming Life, that is “equivalent to the amount gained from production related genetic improvement. The heritability of immune genetics at 25% is similar to that for milk production traits, and far higher than those for longevity (8-10%), calving ease (6-7%), daughter fertility (4-7%) and mastitis (10%).”
If you want to know all the scientific particulars, then you’ll be interested in Mallard’s paper on HIR. If you prefer a quick overview, take a look at the short video below.
Mallard says her next step is to confirm the health of the daughters of HIR sires and implement further genomic studies in HIR technology.
