Project Number: 1265-32000-084-03
Project Type: Specific Cooperative Agreement

Start Date: Sep 29, 2008
End Date: Sep 30, 2009

Objective:
The objective of this study is to identify the level of infection with gastrointestinal nematodes found in American cow-calf operations in the United States, and to assess the effectiveness of current parasite control programs and the efficacy of commonly used anthelminics in control of the parasites.

Approach:
As part of the USDA,APHIS, NAHMS 2008 cow-calf survey American cattle producers were given the opportunity to submit samples to participating laboratories (USDA, ARS, BFGL, University of Minnesota, and Colorado State University. Samples could be collected at any time from March to December, and usually coincided with a deworming treatment, or some other management practice. Samples were taken prior to deworming (Phase 1) or 2 weeks after deworming (Phase 2). Producers were given the option to participate in either Phase 1 only or both Phase 1 and Phase 2. Sampling consisted of taking a golf-ball sized sample from 20 fresh fecal pats per group of animals. Sampling is restricted to animals from 6 -18 months of age. Within 24 hours of sample collection samples are sent to one of the collaborating labs as determined randomly by APHIS. At the lab fecal samples are examined and enumerated for parasite eggs. In addition, eggs are taken from select samples for analyses by PCR for the parasite genera present. This study is the first ever large scale comprehensive look at nematode parasitism in cattle in the U.S. and is the first attempt to define the extent of anthelmintic resistance in American cattle operations.