Study focuses on rumen acidosis

Study focuses on rumen acidosis

SASKATOON — Rumen health is an animal welfare issue, say re-searchers, and its effects on cattle health are now being explored.

Greg Penner, an assistant professor and researcher from the University of Saskatchewan, is exploring the effects of sub-acute rumen acidosis, the kind that doesn’t kill the animal but may affect its health and productivity.

“Hopefully I’m going to convince you that the health of the gastro- intestinal tract is critical in determining the risk of health consequences for cattle,” he told an International Symposium on Beef Cattle Welfare held June 5-7 in Saskatoon.

Acidosis is primarily a problem in beef cattle on heavy grain finishing diets, although it can also affect cattle on lush pasture or on any high energy or highly fermentable diet.

Rapid diet changes can contribute to acidosis, as can a return to feed after recovery from an illness or other semi-prolonged absence from usual rations.

Penner’s research and that of other scientists show cattle can compensate for rumen acidity by adjusting their feed intake or increasing saliva production.

He also said some cattle are more resistant to acidosis.

If acid production in the rumen progresses over time, the composition of the microbes in the gut changes.

Normal barriers in the rumen that prevent toxins from entering the animal’s bloodstream can weaken. Absorption of fatty acids can also be impaired, affecting productivity.

Cattle with sub-acute rumen acidosis can be predisposed to secondary disease such as laminitis or liver abscesses. If prolonged, the rumen could stop functioning.

“I think we are in a position with our feeding systems where we really need to consider rumen health in terms of our obligation to producing healthy animals with limited compromise to animal health,” said Penner.

His research now focuses on understanding the mechanisms associated with acidosis so that practical tools can be developed to control or prevent it.

Reynold Bergen, science director for the Beef Cattle Research Foundation, said research on rumen acidosis is important, but the condition itself is hard to objectively measure.

The research often involves fistulated cattle, which have openings created in their rumens so contents can be extracted and tested.

“We do need to keep in mind that we’re lacking data on rumen pH in commercial sites where cattle might be fed more frequently and are certainly going to be influenced more by large group feeding behaviour,” said Bergen.