Anthelmintic Resistance in Meat Goats
Fecal egg count data from the Western Maryland Pasture-Based Meat Goat Performance Test and Eastern Oklahoma State College Buck Test were analyzed to determine trends in anthelmintic resistance in US meat goats. Data from weaned buck kids from private farms in 21 states were included in the data set.
Both tests evaluated growth and response to natural parasitic infection on pasture-based diets. Bucks were dewormed upon arrival with multiple dewormers. Fecal samples were collected upon arrival (FEC1) and 10 to 13 days later (FEC2) to determine fecal egg count reductions (FECR).
FEC varied by year. In Maryland, FEC1 ranged from 813 ± 519 epg to 3014 ± 454 epg. FEC2 ranged from 14 ± 151 epg to 1036 ± 178 epg. Fecal egg count reduction ranged from 60% to 96% and averaged 82.1 ± 4.7%. In Oklahoma, FEC was 2311 ± 457 epg and 426 ± 142 epg on day 0 and 10 to 13 days later, respectively. FECR ranged from 47.6% to 98.6% and averaged 73.4 ± 5.8%.
While FECR varied among years, data suggest a high prevalence of poor efficacy of anthelmintic treatment. Producers that rely on grass production systems that favor GIN development as represented in these buck tests must practice smart use of anthelmintics.