Pour‐on administration of eprinomectin to lactating dairy goats: Pharmacokinetics and anthelmintic efficacy

Abstract

Goats are primarily kept for milk and meat, and to a lesser extent for production of leather and fiber products (Skapetas & Bampidis, 2016). Globally, parasites, both internal and external, are the most important concern for goat health and productivity. Parasite infections, especially under grazing conditions, constitute a major production limiting problem, predispose to various non-parasitic

Pharmacokinetic-pharmacodynamic relationships of pour-on administered eprinomectin in nematode-infected lactating female and male castrated dairy breed goats

“…This was in line with the (calculated) pooled efficacy of 97.6%. In lactating female goats, the observed AUC last was similar to the predicted value (23.8 vs 25.4 day*ng/mL) and correlated with the observed EPM efficacy of 97.0%, which indicates that minimum nematocidal drug concentrations were maintained over a sufficient time to achieve the required efficacy as discussed previously (Hamel et al 2021).…”

“…The dosage for goats is, nevertheless, a matter of debate, mainly focusing on female dairy goats as lactation is considered a physiological covariate which may alter the pharmacokinetics (PK), and thus, the pharmacological response or anthelmintic efficacy of EPM (Dupuy et al 2001;Lespine et al 2012;Rostang et al 2020). Apart from an earlier PK (only) study in lactating female dairy goats (Dupuy et al 2001), only one publication presents PK and efficacy data established in the same study in lactating female dairy goats that confirms the efficacy of a single pour-on EPM treatment at 1 mg/kg against induced infections with a range of important gastrointestinal and respiratory nematodes of goats (Hamel et al 2021).…”

“…Eprinomectin (EPM) is a macrocyclic lactone characterized by a broad spectrum of endoparasiticidal and ectoparasiticidal activity and low milk partitioning (Shoop et al 1996a). These favorable properties allow for its use as an antiparasitic treatment in veterinary medicine, especially as a topical EPM 5-mg/mL product for pour-on administration to cattle, sheep, and goats with 0-h milk withdrawal (Shoop et al 1996b;Shoop and Soll 2002;Hamel et al 2017Hamel et al , 2021.…”

“…It is accepted that goats need EPM administered as a pour-on at a higher dosage compared to cattle (1-mg/ kg bodyweight vs 0.5-mg/kg bodyweight, respectively) (Chartier and Pors 2004;Cringoli et al 2004;Hamel et al 2015Hamel et al , 2021Rehbein et al 2014). The dosage for goats is, nevertheless, a matter of debate, mainly focusing on female dairy goats as lactation is considered a physiological covariate which may alter the pharmacokinetics (PK), and thus, the pharmacological response or anthelmintic efficacy of EPM (Dupuy et al 2001;Lespine et al 2012;Rostang et al 2020).…”

“…To further corroborate the marketed dosage in goats of pour-on EPM (1-mg/kg bodyweight), results of a series of four combined efficacy and PK studies in lactating female and male castrated growing dairy breed goats (Rehbein et al 2014;Hamel et al 2015Hamel et al , 2021 were retrospectively analyzed to investigate the PK-PD relationship of the pour-on EPM treatment, as an in-depth understanding of the anthelmintic properties of formulated products is a prerequisite for their effective use (Vercruysse et al 2018).…”