Geni Wren In a webcast hosted by Bovine Veterinarian, parasitologist Lou Gasbarre, PhD, discussed parasite resistance and the emergence of some parasites in cattle. One of the parasites of concern that Gasbarre spoke about in the webcast sponsored by Merck Animal Health was Cooperia punctata.
Gasbarre said until recently Cooperia wasn’t really on the radar screen. But a small feedlot study done in Texas showed that Cooperia punctata infection has negative production effects. In that study, calves were first cleaned up with fenbendazole and levamasole, then normal processing (vaccines, etc.) were given. Animals were preconditioned for a month before the study.
Cattle were fed a standard feedlot ration, and the researchers used the GrowSafe® feeder node system to measure individual feed consumption. Half of the study cattle were orally inoculated with Cooperia punctata, the others given tap water. They were then a second dose two weeks later. Gasbarre says the dose was given to mimic what had been seen in nature on pasture. The goal was to get a pure Cooperia punctata infection of around 100 eggs per gram.
At the end of the trial, Gasbarre said there was a significant decrease in the average daily gain and the average consumption of groups with Cooperia punctata infections. “Average daily gain was down 7% in affected calves and consumption was down 4%,” Gasbarre said. “Both were significant at the .02 level.”
Gasbarre says a pure C. punctata infection can have a severe negative effect on the productivity of animals. Direct effects of parasitism can be anorexia, interference with digestion, increased gut motility, disruption of fluid and mineral homeostasis. Significant indirect effects include immune suppression, general and specific hyporesponsiveness, initiation of immunopathology and physiologic responses adverse to productivity.
“Cooperia punctata seems to be an extraordinarily strong inducer of the immune system in the gut,” Gasbarre says. “We need to find out how we can make these parasitized guts healthy again.”
Watch/listen to the webcast anytime here.