Resistance of strongylid nematodes to anthelmintic drugs and driving factors at Czech goat farms

Abstract

Background: Strongylid nematode infections may negatively affect both animal health and welfare, with deleterious consequences for livestock productivity. Many farmers in recent decades have relied on anthelmintics as the sole strategy of control, but the intensive use of these chemotherapeutics has led to the development of anthelmintic resistance (AR). Knowledge of both the efficacy of anthelmintics and factors promoting AR are essential to effectively control nematode infections, but no information on these topics for goats in the Czech Republic (CR) is available. This survey aimed to determine the occurrence of AR at Czech goat farms and to identify risk factors for the development of AR. A total of 24 herds of dairy goats across the CR were evaluated using in vitro tests for detecting AR, and a questionnaire survey was carried out to evaluate factors associated with AR.Results: Resistance against benzimidazoles was confirmed at 75% of the farms, and the level of resistance was high in 22% of the affected herds based on the egg hatch test. Ivermectin-resistant nematodes were detected in 54% of the herds using the larval development test; Teladorsagia/Trichostrongylus and Haemonchus were the predominant types of resistant larvae. More than half (62%) of the affected herds were evaluated as highly resistant to ivermectin. Almost half (46%) of the herds were resistant to both benzimidazoles and ivermectin. This report is the first on multiple AR in the CR. A univariate logistic regression analysis indicated that a high stocking rate and farmer inexperience were significantly associated with ivermectin and benzimidazole resistance, respectively.Conclusions: The results of our survey suggest that AR is widespread amongst herds of dairy goats in the CR, likely due to inappropriate practices of pasture and health management. Multiple AR may be an issue for expanding dairy-goat production in the CR in the near future unless both veterinary practitioners and farmers widely adopt strategies to prevent the development of AR.

Anthelmintic resistance status of goat gastrointestinal nematodes in Sing Buri Province, Thailand

“…In Thailand, benzimidazoles and macrocyclic lactones are commonly used in goat herds. Anthelmintic resistance (AR) to all three groups of anthelmintics are described in several goat raising areas globally [2,[4][5][6][7][8]. Evidence of resistance to all three groups of anthelmintics is frequently reported in goats in Thailand [9][10][11].…”