Assessment, management, and control of internal parasites in beef cattle production systems
Keywords:parasite management, anthelmintic resistance, refugia, fecal egg count reduction test
Gastrointestinal nematodes are important pathogens of cattle due to their negative impact on both health and productivity at the individual and herd level. Chemical control has historically been a highly effective means of controlling parasites and, as a result, is frequently the sole method of control used on many farms. Consequently, numbers of reports of anthelmintic resistance are increasing worldwide, including reports in the United States. To help monitor the efficacy of anthelmintics on individual farms, veterinarians should recommend testing for resistance to all of their producers. Alternative control strategies, such as targeted selective treatment and pasture management, should be used with good drug stewardship to slow the development or progression of anthelmintic resistance and preserve the efficacy of these drugs.