Pharmacokinetics and milk excretion pattern of eprinomectin at different dose rates in dairy cattle

Abstract

Parasite diseases cause productivity losses in dairy animals, with economic effects that can be reduced using anthelmintic therapy (Vercruysse & Claerebout, 2001). Despite their benefits, anthelmintics used in dairy cows cause public health and food safety concerns due to the unwanted presence of drug residues in milk (Imperiale et al., 2004;Tsiboukis et al., 2013). Macrocyclic lactones (MLs) are anthelmintic drugs with endo-and ectoparasiticidal activity (Campbell, 1983;Vercruysse & Rew, 2002). Overall, MLs are considered to have similar biological activity; however, differences in the chemical structure among MLs members account for specific pharmacokinetic (PK) and pharmacodynamic (PD) features (Lanusse, 1997). In addition, the ML structure also has a significant effect on the distribution rate between milk and plasma and, consequently, on the presence of drug residues in milk (McKellar & Gokbulut, 2012). This topic is an important factor influencing the selection of treatments to be applied in dairy animals, considering the importance