Anthelmintic Usage in Feedlot Cattle

To Worm or Not To Worm

Abstract

Cattle feeding in the United States has changed dramatically over the past two decades. In the past, most of the cattle were fed by farmer-feeders in lots with less than 1000 head capacity. Today the majority of cattle fed are in much larger lots. Colorado feedlots last year fed approximately 2.4 million head of cattle and about one half of these were fed in lots with a capacity of over 32,000 head. All indications today point to this trend continuing with more and more cattle being fed in larger lots. As these lots have become larger, management practices have also changed. Cattle feeders are no longer farmers and cowboys, rather they are businessmen who know the entire cattle industry.

As the cattle feeding industry has changed, so has the role of the feedlot veterinarian. The veterinarian is no longer asked to vaccinate, dehom, castrate or even treat most sick animals in the feedlot. The role of the feedlot veterinarian today is to advise and consult the feedlot operator. To do this effectively, the veterinarian must also understand the entire cattle industry and give economically sound advice to management. Part of that advice is an internal parasite control program which does not cost the producer but rather makes money for him. It may not sound like much when you figure it only costs $1.50 to $3.00 to worm a 700 pound steer, but when you worm 30,000 animals and the cost is $45,000 to $90,000 you talk real money. This brings me to the title of this paper: To Worm or Not To Worm.