EFFICACY OF FOUR ENDECTOCIDES AGAINST NEMATODIRUS HELVETIANUS IN CATTLE : MOXIDECTIN, IVERMECTIN, DORAMECTIN 1 % INJECTABLE SOLUTIONS AND MOXIDECTIN 0 .5 % POUR-ON SOLUTION

The efficacies of moxidectin 1% injectable solution (CYDECTIN(R), Cyanamid), moxidectin 0.5% pour-on (CYDECTIN(R), Cyanamid), ivermectin 1% injectable (IVOMEC(R), MSD Agvet) and doramectin 1% injectable (DECTOMAX(R), Pfizer) were estimated in young calves experimentally infected with Nematodirus helvetianus. The post treatment egg excretion was highly decreased in the two moxidectin groups while it remained similar to the control group in both ivermectin and doramectin groups. Based on post mortem worm counts, the efficacies of moxidectin against adult N. helveiianus were excellent (100% and > 99% respectively for the pour-on and the injectable formulations). The efficacies of ivermectin and doramectin were lower (44% and 35%, respectively).