Steelman C D, McNew R W, Simpson R B, Rorie R W, Phillips J M, Rosenkrans C F
Arkansas Agricultural Experiment Station, University of Arkansas, Fayetteville, AR 72701, USA.
J Econ Entomol. 2003 Jun;96(3):892-901. doi: 10.1093/jee/96.3.892.
A 3-yr study was conducted to determine the efficacy of tactics that could be used to manage populations of insecticide-resistant horn flies, Hematobia irritans irritans (L.). Insecticide spray, spot-on or pour-on formulations and two IGRs in bolus formulation, 1.3- and 3.2-ha pasture rotations on different rotation schedules, 0-50% Brahman breeding, selected fly-resistant cows, and a mechanical trap were evaluated singly and in combination. Concentration-mortality tests indicated that horn flies collected from cows used in the current study were significantly less susceptible to diazinon, coumaphos, and methoxychlor than horn flies from cows at the same locations previously used to determine baseline susceptibility. During the 3-yr study at the Southeast Research and Extension Center (SEREC), the IGR-bolus significantly reduced (P < 0.05) horn fly numbers on both the continuous and rotational graze regimens, resulting in significantly (P < 0.05) greater calf weaning weights (average of 24 kg). Horn fly numbers were significantly greater on untreated cows during the 3-yr study at the Southwest Research and Extension Center (SWREC) compared with the mean fly numbers on cows that received fly-management treatments. All tactics and tactic-combinations used at SWREC on cattle having no Brahman breeding failed to significantly reduce insecticide-resistant horn fly numbers. However, the combination of Brahman breeding with the IGR-Bolus and mechanical trap significantly reduced horn fly numbers and resulted in significant increases in calf weaning weight. In addition, mean horn fly numbers decreased significantly as the percentage Brahman breeding increased with 50% Brahman breeding reducing horn fly numbers by 140 flies per cow. No significant difference was found between the mean fly numbers on the fly-resistant purebred group and the cows that had no Brahman breeding but received the IGR-Bolus or used the mechanical trap. The use of synergized zeta-cypermethrin pour-on treatment successfully complimented the use of IGR-bolus and mechanical traps in reducing insecticide-resistant horn fly numbers. Neither 1.3- nor 3.2-ha size paddocks and stocking rates used in the rotation graze regimens at SEREC and SWREC, respectively, significantly reduced horn fly numbers when compared with continuously grazed paddocks. Data indicated the importance of using tactics that reduce horn fly numbers to approximately 150 horn flies per cow. These data demonstrated the efficacy of using tactic combinations to manage insecticide-resistant horn fly populations.
开展了一项为期3年的研究，以确定可用于控制抗杀虫剂角蝇（血蝇）种群的策略的有效性。评估了杀虫剂喷雾、点滴剂或浇泼剂配方以及两种丸剂配方的昆虫生长调节剂（IGR）、不同轮作计划下1.3公顷和3.2公顷牧场的轮牧、0 - 50%婆罗门牛繁殖、选择抗蝇奶牛以及一种机械诱捕器，这些单独使用或组合使用。浓度 - 死亡率测试表明，与之前用于确定基线易感性的同一地点奶牛身上采集的角蝇相比，从本研究中使用的奶牛身上采集的角蝇对二嗪农、蝇毒磷和甲氧滴滴涕的敏感性显著降低。在东南研究与推广中心（SEREC）进行的3年研究中，IGR丸剂在连续放牧和轮牧方案中均显著降低（P < 0.05）了角蝇数量，从而显著（P < 0.05）提高了犊牛断奶体重（平均增加24千克）。在西南研究与推广中心（SWREC）进行的3年研究中，未处理奶牛身上的角蝇数量显著高于接受蝇类管理处理的奶牛的平均蝇数。在SWREC，对没有婆罗门牛繁殖的牛使用的所有策略和策略组合均未能显著减少抗杀虫剂角蝇数量。然而，婆罗门牛繁殖与IGR丸剂和机械诱捕器的组合显著减少了角蝇数量，并使犊牛断奶体重显著增加。此外，随着婆罗门牛繁殖比例的增加，平均角蝇数量显著下降，50%婆罗门牛繁殖使每头牛的角蝇数量减少了140只。在抗蝇纯种组奶牛和没有婆罗门牛繁殖但接受IGR丸剂或使用机械诱捕器的奶牛身上，平均蝇数没有显著差异。增效氯氰菊酯浇泼剂处理的使用成功地补充了IGR丸剂和机械诱捕器在减少抗杀虫剂角蝇数量方面的作用。与连续放牧的围场相比，SEREC和SWREC轮牧方案中分别使用的1.3公顷和3.2公顷大小的围场以及载畜率均未显著减少角蝇数量。数据表明，使用将角蝇数量减少到每头牛约150只角蝇的策略非常重要。这些数据证明了使用策略组合来控制抗杀虫剂角蝇种群的有效性。
