College of Veterinary Medicine, China Agricultural University, Beijing 100193, China.
College of Veterinary Medicine, China Agricultural University, Beijing 100193, China.
Vet Parasitol. 2023 Aug;320:109983. doi: 10.1016/j.vetpar.2023.109983. Epub 2023 Jul 10.
Dermanyssus gallinae, the poultry red mite (PRM), is an obligate ectoparasite feeding on poultry blood, seriously affecting the health of layers and egg production. The control of PRMs mainly relies on chemical drugs, which is facing several challenges such as the environment pollution and drug resistance. Using fungal metabolites is an environmentally friendly alternative for the control of pests. However, few studies have been conducted on the efficacy of fungal metabolites against D. gallinae. In this study, five strains of fungi were isolated from D. gallinae under laboratory conditions, and their extracts with ethyl acetate were tested for acaricidal activity on D. gallinae. The crude extract of Aspergillus oryzae caused 75.55 ± 6.94% mortality of mites at a concentration of 12.5 mg/mL, showing the highest acaricidal effect in all extracts. Subsequently, the extract of A. oryzae was isolated by bio-guided fractionation, and ten major compounds were identified by LC-MS/MS analysis. The results of bioassays indicated that five compounds exhibited acaricidal activity against D. gallinae. N, N-dimethyldecylamine N-oxide was the optimal acaricidal compound with LC of 0.568 mg/mL. Additionally, palmitic acid, triethanolamine, cuminaldehyde, and 2,4-dimethylbenzaldehyde also showed acaricidal activity. These compounds have great application potential in the mite control, and the analysis of these fungal acaricidal substances provides a new idea and basis for the subsequent development of PRM control technology.
鸡皮刺螨（PRM），又称家禽红螨，是一种专性外寄生虫，以家禽血液为食，严重影响蛋鸡的健康和产蛋性能。PRM 的防治主要依赖于化学药物，但面临环境污染和抗药性等挑战。利用真菌代谢产物防治害虫是一种环保的替代方法。然而，目前关于真菌代谢产物对 D. gallinae 的防治效果的研究较少。本研究从实验室条件下分离的鸡皮刺螨中分离出 5 株真菌，并测试了它们的乙酸乙酯提取物对 D. gallinae 的杀螨活性。曲霉（Aspergillus oryzae）的粗提物在 12.5mg/mL 浓度下对螨虫的致死率为 75.55±6.94%，在所有提取物中表现出最高的杀螨效果。随后，通过生物导向分离对曲霉提取物进行分离，通过 LC-MS/MS 分析鉴定了 10 种主要化合物。生物测定结果表明，有 5 种化合物对 D. gallinae 具有杀螨活性。N,N-二甲基十二烷基氧化胺（N, N-dimethyldecylamine N-oxide）是最佳的杀螨化合物，LC 为 0.568mg/mL。此外，棕榈酸、三乙醇胺、桂醛和 2,4-二甲基苯甲醛也具有杀螨活性。这些化合物在控制螨虫方面具有很大的应用潜力，对这些真菌杀螨物质的分析为后续 PRM 防治技术的发展提供了新的思路和依据。
