Exposure to agrochemicals and pathogens has been indicated as critical factors of declining pollinator populations, including species of native tropical bees. In the present study, we investigated the sublethal effects of acute oral exposure to azadirachtin and spinosad bioinsecticides on the expression of immunity-related genes and the number of hemocytes in uninfected and Escherichia coli–infected workers of the stingless bee Melipona quadrifasciata. Expression of the immune-related gene vitellogenin decreased and the number of circulating hemocytes increased in bioinsecticide-exposed uninfected bees and in unexposed E. coli–infected bees as compared with unexposed uninfected bees. Our results show that though bioinsecticides are considered safe, contamination by sublethal doses of azadirachtin and spinosad can interfere with the immune system of bees.

中文翻译：

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口服接触印楝素和多杀菌素后，Melipona quadrifasciata (Apinae: Meliponini) 先天免疫反应和解毒的变化

接触农用化学品和病原体已被认为是导致授粉媒介种群（包括本地热带蜜蜂物种）下降的关键因素。在本研究中，我们研究了急性口服印楝素和多杀菌素生物杀虫剂对未感染和感染大肠杆菌的无刺蜂 Melipona quadrifasciata 工人的免疫相关基因表达和血细胞数量的亚致死影响。与未暴露的未感染蜜蜂相比，暴露于生物杀虫剂的未感染蜜蜂和未暴露的大肠杆菌感染蜜蜂的免疫相关基因卵黄蛋白原的表达降低，循环血细胞数量增加。我们的结果表明，虽然生物杀虫剂被认为是安全的，