Impact of Treatment of Beef Cows with Ivermectin on Herd Productivity

Abstract

Internal parasite control in commercial beef cow-calf operations in western Canada has, until recently, not been considered an important part of herd management. Recent epidemiological studies conducted in the region indicate however, that the cow is an important source of pasture contamination and hence infection for the calf (1). Studies conducted in North Dakota have demonstrated improved productivity and economic returns associated with treatment of the cow herd with ivermectin (2,3). Similar studies have not been published for western Canada.The objective of this study was to evaluate the productivity impact of a fall treatment with ivermectin of commercial beef cows. The effect of treatment was evaluated by monitoring the body condition and reproductive performance of cows and by measuring calf weight gains.