Efficacy of eprinomectin pour-on in naturally Oestrus ovis infested merino sheep in Extremadura, South-West Spain

Abstract

The aim of this study is to evaluate the efficacy of the eprinomectin pour-on in naturally Oestrus ovis-infested sheep. To carry out this trial, 14 naturally infected sheep from the same flock were used. The animals were randomly distributed in three groups: group 1 (non-treated sheep), group 2 treated with 0.5 mg/kg bodyweight and group 3 treated with 1 mg/kg bodyweight of eprinomectin. The sheep were slaughtered 15 days after treatment and their heads were sectioned to count and identify larvae instar. The following results were obtained: Group 1: the average was 34 live and 0.75 dead larvae per sheep. Group 2: the efficacy of the eprinomectin was 83.5% against O. ovis group 3: the efficacy of the eprinomectin pour-on was 100%. Drug analysis was made to determine plasma eprinomectin concentration 9 days after treatment and the average concentrations in groups 2 and 3 were 1.23 and 3.04 ng/ml, respectively. The statistical study showed a significant difference between the efficacy and the dose used, and there was correlation between the plasma concentration of eprinomectin and the dose. The efficacy and easy application allow us to take into account this endectocide as an alternative method in the integral control of parasites in sheep.

Os parasitas de ovinos

“…O controle do parasitismo por O. ovis é feito exclusivamente com o uso de antiparasitários, tais como os organofosforados (triclorfon), closantel e as lactonas macrocíclicas, como a ivermectina (Dorchies et al, 1997a;Lucientes et al, 1998), moxidectina (Dorchies et al, 1996), doramectina (Oliveira et al, 2000;Dorchies et al, 2001), eprinomectina (Hoste et al, 2004;Habela et al, 2006) e também rafoxanida (Sanyal et al, 1986) e nitroxinil.…”

Application of the Analysis of Serum Antibodies (Immunoglobulins M and G) to Estimate the Seroprevalence of Ovine Oestrosis and to Evaluate the Effect of Chemotherapy

“…These results agree with that from Lucientes et al (1998), who reported that the efÞcacy of ivermectin administered orally at a dosage rate of 0.2 mg/kg liveweight against naturally acquired larval infestations of O. ovis in sheep was 100% in a Þeld trial. By the pour-on application of eprinomectin, percentages of successful treatment higher than 97% have been obtained (Hoste et al 2004;Habela et al 2006).…”

“…Although there are several parasiticides efÞcient against O. ovis larvae, the evaluation of their success requires that sheep be slaughtered (Lucientes et al 1998;Habela et al 2006). In this study, an ELISA was used to determine the changes in the humoral immune response of O. ovis-infested sheep, after treatment with ivermectin.…”

“…The possibility of infection in humans remarks the need for appropriate control measures, like chemotherapy (Fekry et al 1997). Although there are several parasiticides useful for the treatment of oestrosis (Lucientes et al 1998;Habela et al 2006), sheep are slaughtered to evaluate their efÞcacy.…”

Efficacy of eprinomectin against Toxocara vitulorum in calves

“…Eprinomectin has also been used for the treatment of ectoparasites of farm animals (Aguirre et al 2005;Rehbein et al 2005;Habela et al 2006). Oral administration of eprinomectin in dogs has been reported to be 100% effective against Toxocara canis infection (Kozan et al 2008).…”