01913naa a2200289 a 450000100080000000500110000800800410001910000160006024501750007626000090025152010310026065000180129165000180130965000180132765000350134565000250138065000170140565300190142265300130144165300130145465300140146770000170148170000200149870000200151870000210153877300640155917858852009-01-12       1978    bl ---       0--  u    #d1 aHALL, C. A.  aThe dose response of several benzimidazole anthelmintics against resistant stains of Haemonchus contortus and Trichostronngylus colubriformis selected with thiabendazole.  c1978  aDoses responses lines for eight benzimidazole anthelmintics and thiophanate were deter- mined, using standardised strains of thiabendazole selected and resistant Haemonchus contortus and trichostrongylus colubriformis. Against H contortus, thiophanate, thiabenda- zole, parbendazole oxibendazole were inactive. Mebendazole was inactive at dose rates of 6.26 and 12.5 mg/kg, although significantly activity occurred at 25 mg/kg. Fenbenda- zole, cambendazole, oxfendazole and albendazole demonstrated significant activity at dose rates equal to or greater than the recommended therapetic level. Thiophanate was inactive against resistant T colubriformis. The remaining compounds only showed signifi- cant activity when used at dose rates in excess of the recommended therapeutic level. These results show that a side resistante exists among the benzimidazole anthelmintics and suggests that changes in dose response lines could be expected to occur if resistant strains are selected with benzimidazoles other than thiabendazole.  aanthelmintics  abenzimidazole  athiabendazole  aTrichostrongylus colubriformis  aHaemonchus Contortus  aResistência  aAntehelmintico  aParasita  aParasite  aResistant1 aKELLY, J. D.1 aCAMPBELL, N. J.1 aWHITLOCK, H. V.1 aMARTIN, I. C. A.  tResearch in Veterinary Sciencegv.25, n.3, p.364-367, 1978.