Anthelmintic Use in Dairy Farming: Describing correlations of Defined Daily Dose and known risk factors

Abstract

Anthelmintic resistance poses an increasing threat to livestock farming worldwide. It is known that anthelmintic use is a risk factor for development of anthelmintic resistance. Insight into current use and factors associated with high anthelmintic use are currently unknown in dairy farming in the Netherlands. Since dairy farming is an important agricultural practice in the Netherlands, there is urge to fill this knowledge gap. This study aimed to quantify the usage of anthelmintics in a Defined Daily Dose (DDD) on Dutch dairy farms and identify which factors are correlated with DDD. In total 96 farms participated in two questionnaires, of which 78 farms provided information about their usage of anthelmintics used in the calculation of the DDD. Seven generalized linear models were fitted, for seven distinct groups (animal age groups, helminth categories and a total DDD). A mean of 21.5 doses per animal per day was defined with a standard deviation of 27.0 for the total DDD. In the models fitted, factors such as treatment practices, preventative measures, feeding practices and herd compositions were significantly associated with variation in the DDD of anthelmintics on Dutch dairy farms. The results underline the importance of management strategies and preventative measures of helminths regarding anthelmintics usage.