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Helping Farmers Make Better Herd Management and Breeding Decisions
High Immune Response Technology Identifies Animals with Superior Immunity, say Researchers
By Karli Longthorne
Reducing disease and improving animal health have been long-standing goals for the Ontario beef industry and its farmers, particularly with the high incidence of bovine respiratory disease (BRD).
BRD—a disease in the upper or lower respiratory tracts caused by bacterial or viral pathogens— has been identified by the Canadian Cattlemen’s Association as the most common and costly disease affecting the North American beef industry. BRD rates remain unchanged despite advancements in medicine and Canadian beef production management strategies.
That’s where University of Guelph Prof. Bonnie Mallard, Department of Pathobiology at the Ontario Veterinary College, and a team of researchers, including Dr. Julie Schmied and Dr. Douglas Hodgins, as well as graduate students Nasrin Husseini, Shannon Beard and Shannon Cartwright, come in.
The Mallard lab was the first to develop a genomics test for Holsteins that determines associations between an animal’s specific set of immune response genes and their ability to fight disease, using High Immune Response (HIR™) technology. Now this group is looking to adapt this technology for use in Angus beef cattle.
The HIR technology identifies animals with superior immune responses by evaluating antibody and cell-mediated immune responses, allowing for the calculation of an estimated breeding value or expected progeny difference for total immune response for each animal.
This means cattle farmers can determine early in life which animals have superior health and which are at increased disease risk. They will also be able to select and breed animals better able to fight disease by selective breeding of high immune responders, while fostering healthier herds.
“Our research makes a difference for producers, animals and consumers. Producers will save time and money on the treatment of sick animals by minimizing the use of antibiotics and other therapeutic interventions,” says Mallard. “By bringing the HIR technology into the beef market, consumers can feel good knowing that their food came from naturally healthy animals that were raised in a healthy and sustainable manner.”
A genomics test similar to that used for dairy cattle will be valuable to the beef industry because immune response traits have not yet been incorporated into breeding programs for beef cattle. Their inclusion has the potential to improve overall animal health and enhance disease resistance, including within the context of climate change and calf health.
Climate change is also taking a toll on the livestock industry, making it difficult for livestock to adapt to the constantly changing environment, particularly global warming. The HIR phenotypic test and the researcher’s genomics test may also help identify cattle who are better able to adapt to climate change, as preliminary research in both beef and dairy cattle performed at the Elora Research Station suggests cows that have high immune responses could better adapt to heat stress.
The HIR tests are expected to allow beef producers to identify the traits in beef cattle that could improve calf health. Previous research shows that dairy cows that are high immune responders have better quality colostrum, providing their calves colostrum with greater amounts of antibody. Immune response is a moderately heritable trait, meaning a dam identified as a high responder will also pass these superior immune response genes onto her calf.
Currently, the researchers are building a reference population of 4,000 beef cattle by using the HIR technology to phenotype (i.e., observe an animal’s physiological immune response characteristics) purebred Angus cattle across North America.
So far, a preliminary study done at the University of Guelph’s Beef Research Centre and in North American commercial herds has found there is sufficient variability in these heritable immune response traits in beef cattle to identify which are high, average or low immune responders.
Past research utilizing the HIR technology in pigs and dairy cattle have shown many benefits for livestock producers. Dairy farmers have the ability to use this technology through breeding or genomically testing their cattle using the HIR/Immunity+ platform marketed by the Semex Alliance. This research could provide beef producers with the same opportunity dairy producers currently have, allowing them to capitalize on the benefits of the HIR technology to improve livestock health and wellbeing.
After the researchers have collected the HIR phenotypes in their Angus reference population, they plan to validate these phenotypes with key health and production factors such as morbidity, mortality and use of antibiotics. OB
This research is funded by Food from Thought, with thanks in part to funding from the Canada First Research Excellence Fund and the Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA), through the Ontario Agri-Food Innovation Alliance to adapt HIR for beef and evaluate the effects of heat stress on bovine health. Additional funding is provided by Genome Canada’s Genomic Applied Partnerships Program with contributions from The Semex Alliance, Angus Genetics Inc. and the Canadian Angus Association.
The Elora Research Station is one of 15 Research Stations owned by the Agricultural Research Institute of Ontario and managed by the University of Guelph through the Ontario Agri-Food Innovation Alliance, a collaboration between the Ontario Government and the University of Guelph.
