Excerpts from a paper by Donald H. Bliss, Ph.D., President of MidAmerica Agricultural Research, Parasitologist and industry consultant

Proper deworming strategy adds to production efficiency.
Now more than ever, producers are emphasizing internal parasite control in the production of efficient beef cattle. With the introduction of fenbendazole (Safe-Guard®/PANACUR® Intervet, Inc.) and ivermectin (Ivomec®, Merial) in the 1980s, severe clinical parasitism has all but disappeared as a widespread economically important problem for the U.S. cattleman. Deworming is now standard practice on beef farms, and cattle exhibiting severe parasitism, such as bottled jaw, emaciation and diarrhea, are rare. Because of this emphasis on deworming, parasite control has become a tool to improve the efficiency of cattle.

Therefore, the focus for deworming in the future needs to be on improving production efficiency by using the correct product at the correct time, while creating a least-cost, most-efficient deworming strategy for each operation.

The economic costs of internal parasitism in production animals
Recent field studies indicate that parasitism can play a role in everything from disease control to the immune status of the animal to breeding efficiency and over-wintering ability of brood cows. This feedlot trial demonstrates strategically dewormed cattle have a production advantage due to fewer health problems than non-dewormed cattle.

Comparing the weight gain of non-dewormed cattle with those that were strategically dewormed showed a dramatic difference in performance. The dewormed cattle gained an additional 48 pounds in the pasture, and 50 pounds in the feedyard. The average daily gain difference was substantial. And the differences in overall health and carcass characteristics were also dramatic.

By definition, parasitism is detrimental to the host animal, explains Dr. Wade Nichols with Intervet. Nichols was one of the scientists that worked on the pasture and feedlot study. “Anything we can do to ride the animal of parasites will most likely improve performance and the health of the animal,” Nichols says.

“As a nutritionist, I tend to explain the differences found in these studies through feed intake,” he says. “We know that anytime we can improved feed intake, we generally get better gain and improved health status. As far as the parasitism is concerned, the parasites send signals throughout the animals body which decrease feed intake. They also disrupt nutrient digestion and absorption throughout the digestive tract. Therefore when we rid the animal of parasites we can see increased feed intake, improved digestion, and improved absorption of nutrients. When you improve these parameters this gives the animal more nutrients to utilize for growth parameters and immune function.” ©