Morantel resistance in Trichostrongylus colubriformis.
The occurrence of anthelmintic resistance in Trochostrongylus colubriformis and resistance to morantel are reported for the first time in New Zealand. In two controlled anthelmintic trials with experimentally infected sheep, morantel citrate at either 8.8 mg/kg or 10 mg/kg had no effect on worm burden. An efficacy of >99% was demonstrated for mebendazole at 12.5 mg/kg against this strain.
McKenna
P B
PB
Palmerston North Animal Health Laboratory, PO Box 1654, Palmerston North.
Seifert
D A
DA