Does how a cow is fed during pregnancy impact the life-long performance of her calf?

Beef fetal programming project is underway at University of Guelph

By Lilian Schaer for Livestock Research Innovation Corporation

Work is underway at the University of Guelph to see whether the nutritional treatment of cows during the third trimester of pregnancy has any kind of impact on their calves. Researchers will follow the calves throughout their lives right until processing to assess their health, growth, and other production parameters.

Specifically, they will be measuring the impact of protein and methionine supplementation on both cow performance and subsequent calf health and performance, Prof. Katie Wood told participants at the 2019 Beef Symposium this past winter.

“Fetal programming is a new way to think about how to manage beef cows and in this project we’re looking at what can we do to cows in the last two months before calving that might have positive benefits to the calves,” she said.

Approximately 60 cows at the University of Guelph’s research facility in New Liskeard and 150 cows at the Elora station were fed a series of applied treatments during the last eight weeks of gestation, calving in spring 2018.

In Elora, cows were fed a controlled diet matched to the individual animal to meet their energy requirements but with varying levels of protein: 10% under their requirements, at their required needs and 10% above requirements. Each group was then split again, with half of the animals also receiving a methionine amino acid supplement.

“Feeding an animal amino acids might mean we can get away with feeding a bit less protein,” she said.
“You can maybe feed a lower total protein diet but still benefit from increased absorption and use; this could reduce nitrogen emissions and may be a cheaper way to supplement protein.”

The heifers and steers from those cows are now on trials at Guelph for long-term performance evaluation and will be finished later this summer; final results on calf performance are expected this coming winter.

To date, preliminary results have shown that cows getting only 90% of their protein requirement but with a ration supplemented by methionine seemed to perform as well as those animals receiving protein at or above requirements. By comparison, the cows at 90% protein but without methionine lost body weight.

According to Wood, methionine supplementation is already used in the dairy industry, and although it hasn’t been used much to date by beef farmers, the cost is relatively inexpensive.

“We are looking at about 20 cents per animal per day so if we’re pressed up against nutrient-loading rules, this could be a way to reduce nitrogen loses,” she said, adding this would also depend on the cost of soybean meal and dried distillers’ grains (DDGs).

The research team did see some interesting results on the colostrum side: cows fed methionine had lower urea levels in their colostrum, and their calves showed lower total protein and Immunoglobulin G (more commonly called IgG for short) levels. IgG is responsible for passive immunity.

“We’re still looking into why we are seeing these results, but what might be happening is that the cows are keeping the protein themselves and putting less into the colostrum,” Wood said. “Our results are really interesting because they show that cow diet in late gestation can have a major impact on colostrum composition.”

Colostrum not only contains antibodies important for passive immunity, but also many other growth factors and bioactive components, which may also have an impact on future calf health and growth.

Beef Farmers of Ontario, Agriculture and Agri-Food Canada’s Agri-Innovation Program and the University of Guelph research partnership with the Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA) are funding this fetal programming study.

It’s a project that is tied closely to the construction of the new beef research facility in Elora, Wood said, as funding for the study has enabled the purchase of some top of the line research equipment for the barn that will allow data to be captured on individual animals instead of just on groups of cattle.

“We are very excited to have a new world-class research facility to be able to improve all aspects of beef production, including continuing research on fetal programming in beef cow”, she said.

This article was published in Ontario Beef, August 2019. It is provided by Livestock Research Innovation Corporation as part of LRIC’s ongoing efforts to report on Canadian livestock research developments and outcomes.