Non-confirmation of anthelmintic resistance in Ostertagia spp.
An investigation was undertaken to confirm the existence of a mebendazole-resistant strain of Ostertagia spp. on a ram-breeding property in Taihape. The results indicated that while a strain of Haemonchus contortus from this farm was highly resistant to mebendazole, an isolate of Ostertagia spp. was fully susceptible. Possible reasons for the discrepancy between previous and present findings are briefly discussed.
McKenna
P B
PB
Palmerston North Animal Health Laboratory, P.O. Box 1654, Palmerston North.
Hughes
P L
PL