Tue, 2019/02/12 - 9:29am
Dairy cows are like marathon runners. Making milk at peak production is said to take as much energy as a human running two marathon races per day. As with high-performance athletes, that demand puts stress on cows’ bodies. And that can lead to a common but hard-to-detect condition called ketosis that shows no outward illness.
“Ketosis in cows is clinically very subtle,” says Prof. Stephen LeBlanc, Department of Population Medicine. “If you walked into a barn and there were 100 cows standing around you, you couldn’t tell by looking which cows have ketosis.”
University of Guelph researchers are working to improve the efficiency of ketosis diagnosis, prevention and treatment. It increases the risks of other diseases, premature culling, reduced milk production and fertility. More than 40 per cent of cows experience ketosis at least once per lactation, which costs producers around $300 per affected cow. The accumulated economic burden is substantial.
Using automated systems such as DeLaval’s Herd Navigator to reduce labour in testing milk samples for ketosis and measuring production, LeBlanc and his team determined that the optimal testing frequency for ketosis in cows was three to four times a week, to avoid missing any affected cows.
The next question is whether it’s more beneficial to act immediately and treat at the first detection of ketosis, or to wait and see whether ketosis persists for a few days.
“We’re still looking to optimize therapy,” says LeBlanc. “Existing therapies have cure rates of about 75 per cent for ketosis, but one-quarter of cows still have persistent ketosis. One thing that we’re looking at is what we can do better to drive that success rate up.”
Population medicine researchers on these projects include Prof. Todd Duffield, PhD graduate and former post-doctoral scholar Khaled Gohary, and M.Sc. student Maggie Williamson.
This research is funded by the OMAFRA-U of G Agreement. Additional funding was provided by DeLaval, Mitacs and CanWest DHI.
As seen in the 2017-2018 Agri-Food Yearbook.