Identifying healthier herds
A reliable test to detect cattle with superior immune response is on its way
By Joey Sabljic, SPARK
A University of Guelph research team has developed a safe, accurate way to help identify cows with the strongest, most disease-resistant immune systems — technology that could realize substantial herd health savings plus other benefits.
Prof. Bonnie Mallard, an immunogeneticist in the university’s Department of Pathobiology, PhD candidate Lauraine Wagter-Lesperance and a team of researchers have developed and patented a test called High Immune Response (HIR).
“This is a sustainable, environmentally friendly technology,” Mallard says. “Just as you would breed for milk production, you would breed for optimum immune response using the HIR technology.”
The technology identifies cattle as high, average or low immune responders. High responders have more balanced immune responses capable of defending against the large number of diverse pathogens that infect dairy cattle.
Identifying these animals for a breeding program could lower disease occurrence, greatly reducing veterinary treatment costs (mastitis treatment, for example, can cost $100 per infection plus lost production). It could also increase a herd’s response to vaccinations.
HIR testing and analysis have to be done only once at any stage of an animal’s life from two months of age onward. The procedure is done during three short on-farm visits over a 15-day period.
First, the animal is immunized with a patented test antigen system, similar to a vaccine, to spur its immune system into action. Next, blood or milk samples are taken and analysed to determine the speed and strength of its immune responses to the test antigens.
Researchers then rank each animal according to its ability to pass along its valuable immune genes based on estimated breeding values for immune responsiveness.
The results will enable producers to cull cattle with low-immune response profiles; to select an appropriate bull for breeding, based on the immune profiles of both sire and dam; and to tailor each animal’s vaccinations and management according to its indicated immune response status.
As well, colostrum enriched with higher amounts of protective antibodies from HIR cows could supplement calves during their vulnerable first few days after birth.
HIR’s benefits could also translate to the supermarket. Consumers could enjoy milk products from healthier animals that require far fewer antibiotics and disease treatments over their lifetimes.
“HIR is about animal health,” says Mallard. “But it also has a lot of benefit further on down the line, as it relates to milk and dairy products. It’s a total farm-to-fork idea.”
Mallard and her team are now looking to apply the HIR test system to sires in addition to cows, heifers and calves. Another crucial part of their work will involve forming partnerships to bring HIR into the wider dairy community.
Many colleagues and students have been involved with the HIR project over the last 20 years. Some of the current and more recent students are: Shannon Cartwright, Kathleen Thompson Crispi, Jacqueline Gallienne, Brad Hine, Lauraine Wagter-Lesperance Wagter-Lesperance, Marlene Paibomesai, Claire Martin, Brendan Hussey, Rebecca Opsteen, Neda Emam, Mehdi Emam and Sophia Lim. This research receives funding from the Ontario Ministry Agriculture, Food and Rural Affairs (OMAFRA); the Natural Sciences and Engineering Research Council; and the Canadian Dairy Network.
Photo by Bruce Sargent, SPARK