Entomology and Nematology Department, University of Florida, Gainesville, FL 32611, USA.
Pest Manag Sci. 2010 Mar;66(3):290-4. doi: 10.1002/ps.1872.
The housefly, Musca domestica L., continues to be a major pest of confined livestock operations. Houseflies have developed resistance to most chemical classes, and new chemistries for use in animal agriculture are increasingly slow to emerge. Five adult housefly strains from four Florida dairy farms were evaluated for resistance to four insecticides (beta-cyfluthrin, permethrin, imidacloprid and nithiazine).
Significant levels of tolerance were found in most field strains to all insecticides, and in some cases substantial resistance was apparent (as deduced from comparison with prior published results). At the LC(90) level, greater than 20-fold resistance was found in two of the fly strains for permethrin and one fly strain for imidacloprid. Beta-cyfluthrin LC(90) resistance ratios exceeded tenfold resistance in three fly strains. The relatively underutilized insecticide nithiazine had the lowest resistance ratios; however, fourfold LC(90) resistance was observed in one southern Florida fly strain. Farm insecticide use and its impact on resistance selection in Florida housefly populations are discussed.
Housefly resistance to pyrethroids is widespread in Florida. Imidacloprid resistance is emerging, and tolerance was observed to both imidacloprid and nithiazine. If these insecticides are to retain efficacy, producer use must be restrained.
家蝇（Musca domestica L.）仍然是封闭式牲畜养殖场的主要害虫。家蝇对大多数化学药剂都产生了抗药性，而新的动物农业用化学药剂的研发速度却越来越慢。本研究评估了来自佛罗里达州四家奶牛场的 5 个家蝇品系对 4 种杀虫剂（beta-氯氟氰菊酯、氯菊酯、吡虫啉和硝虫噻嗪）的抗药性。
大多数田间品系对所有杀虫剂都表现出显著的耐受性，在某些情况下，明显存在抗药性（通过与之前发表的结果进行比较得出）。在 LC90 水平，两种家蝇品系对氯菊酯和一种家蝇品系对吡虫啉的抗性超过 20 倍。三种家蝇品系对 beta-氯氟氰菊酯的 LC90 抗性比值超过 10 倍。相对未充分利用的杀虫剂硝虫噻嗪的抗性比值最低；然而，在佛罗里达州南部的一种家蝇品系中观察到 4 倍的 LC90 抗性。本研究讨论了佛罗里达州农场杀虫剂的使用及其对家蝇种群抗药性选择的影响。
佛罗里达州的家蝇对拟除虫菊酯的抗药性广泛存在。吡虫啉的抗药性正在出现，并且对吡虫啉和硝虫噻嗪都表现出了耐受性。如果这些杀虫剂要保持药效，就必须限制生产者的使用。
