DETECTION OF MODERATE ANTHELMINTIC RESISTANCE IN CLOSTANTEL AND MACROCYCLIC LACTONE IN ORGANIZED CENTRAL SHEEP BREEDING FARM OF HARYANA, INDIA

Abstract

This study was performed to evaluate the efficacy of currently used anthelmintics in an organized central breeding sheep farm (CSBF) in Hisar, Haryana using a fecal egg count reduction test (FECRT). A total of 60 sheep were chosen for this study and divided equally into four groups. Sheep were tested with closantel (@10mg/kg body weight) and two derivatives of macrocyclic lactone, moxidectin, and doramectin (@0.2mg/kg body weight) while the control group did not receive any treatment. Sheep were naturally infected with gastro-intestinal nematodes and had EPG of feces more than 150 counts before treatment was selected. Rectal fecal samples were collected on zero (pre-treatment) and 14th day (post-treatment) from animals of all groups and EPG of feces was carried out by modified McMaster technique. In FECRT, reduction of fecal egg count (FEC) of less than 95%, indicates anthelmintic resistance (AR) in one or more nematode genera for the given anthelmintic. Percent of FEC on the 14th day revealed that closantel, moxidectin, and doramectin had 64%, 69%, and 76% efficacy, respectively. Coprocultures from pre- and post-treated sheep revealed a predominance Haemonchus contortus larvae. The result indicated the development of moderate anthelmintic resistance against three anthelmintics, leading to a change of anthelminthic drugs and regular monitoring for possible anthelmintic resistance on the farm.

Keywords

• anthelmintic resistance
• closantel
• macrocyclic lactones
• small ruminants
• fecrt