Williams J C
Department of Veterinary Science, Louisiana Agricultural Experiment Station, LSU Agricultural Center, Baton Rouge 70803.
Vet Parasitol. 1991 Oct;40(1-2):59-71. doi: 10.1016/0304-4017(91)90083-8.
An experiment was conducted to compare the anthelmintic efficacy of albendazole (ABZ), levamisole (LEV) and fenbendazole (FBZ) against inhibited early fourth stage larvae (EL4) of Ostertagia ostertagi during April in Louisiana. Forty cross-bred beef heifers (average weight 165 kg) were acquired during winter and grazed on pastures contaminated with O. ostertagi and other nematodes until early April. The cattle were weighed and randomly allotted into four groups of ten animals on 6 April and treatments were administered on 7 April. Experimental groupings were: Group 1, non-treated controls; Group 2, ABZ by oral drench at 10 mg kg-1; Group 3, LEV by topical, pour-on administration to back midline at 10 mg kg-1; Group 4, FBZ by oral drench at 10 mg kg-1. Equal numbers of cattle from each group were slaughtered daily between 10 and 13 days after treatment. Mean numbers of O. ostertagi developmental stages present in untreated controls were: adults, 13,714; developing L4 (DL4), 6487; inhibited EL4, 21,719. The mean percentage of inhibited EL4 was 51.8. Smaller numbers of Haemonchus placei, Trichostrongylus axei and Cooperia spp. were recovered uniformly in control cattle. Percentage reduction values for the three compounds against O. ostertagi adults, DL4 and EL4, respectively, were: ABZ, 99.0, 95.3, 84.9; LEV, 1.0, 21.8, 32.1; FBZ, 99.2, 97.2, 97.5. Differences between ABZ and LEV EL4 counts were not significant, but in all other cases worm counts in ABZ and FBZ-treated cattle were significantly lower (P less than or equal to 0.05) than in LEV-treated and control cattle. Both ABZ and FBZ were 98-100% effective against Haemonchus adults and L4, T. axei adults, and Cooperia spp. adults and L4. LEV was 100% effective against Haemonchus adults and L4, 85.6% against T. axei, and 94.6% and 89.59% effective against Cooperia spp. adults and L4, respectively.
在路易斯安那州4月期间进行了一项实验，比较阿苯达唑（ABZ）、左旋咪唑（LEV）和芬苯达唑（FBZ）对奥斯特他线虫抑制性早期第四阶段幼虫（EL4）的驱虫效果。40头杂交肉用小母牛（平均体重165千克）在冬季购得，在被奥斯特他线虫和其他线虫污染的牧场放牧至4月初。4月6日对牛称重并随机分为四组，每组10头动物，4月7日进行处理。实验组别如下：第1组，未处理对照组；第2组，按10毫克/千克口服灌服阿苯达唑；第3组，按10毫克/千克在背部中线进行局部浇泼给药左旋咪唑；第4组，按10毫克/千克口服灌服芬苯达唑。处理后10至13天期间，每天宰杀每组相同数量的牛。未处理对照组中奥斯特他线虫发育阶段的平均数量为：成虫13714条；发育中的L4（DL4）6487条；抑制性EL4 21719条。抑制性EL4的平均百分比为51.8%。对照组牛中均一地检出较少数量的柏氏血矛线虫、奥氏毛圆线虫和古柏属线虫。三种化合物对奥斯特他线虫成虫、DL4和EL4的减少百分比分别为：阿苯达唑99.0%、95.3%、84.9%；左旋咪唑1.0%、21.8%、32.1%；芬苯达唑99.2%、97.2%、97.5%。阿苯达唑和左旋咪唑EL4计数之间的差异不显著，但在所有其他情况下，阿苯达唑和芬苯达唑处理的牛中的虫数显著低于（P≤0.05）左旋咪唑处理的牛和对照牛。阿苯达唑和芬苯达唑对血矛线虫成虫和L4、奥氏毛圆线虫成虫、古柏属线虫成虫和L4的有效性均为98 - 100%。左旋咪唑对血矛线虫成虫和L4的有效性为100%，对奥氏毛圆线虫为85.6%，对古柏属线虫成虫和L4的有效性分别为94.6%和89.59%。
