Roychoudhury Sudipta, Kobayashi Mutsuo
Department of Medical Entomology, National Institute of Infectious Diseases, Toyama 1-23-1, Shinjuku-ku, Tokyo-162-8640, Japan.
J Am Mosq Control Assoc. 2006 Mar;22(1):29-36. doi: 10.2987/8756-971X(2006)22[29:NFOTDP]2.0.CO;2.
Infection in different stages of larvae of Aedes aegypti and Ae. albopictus with Ascogregarina taiwanensis and A. culicis, respectively, revealed that the oocysts of Ascogregarina spp. are able to infect any instar and can complete their life cycle within 9.5 +/- 1 days. When early instars ingested oocysts, parasite development was synchronized to larval-pupal ecdysis and oocyst dissemination occurred at the time of adult emergence, oviposition, or both. The parasites also developed normally when infecting 2nd, 3rd, and early 4th instars and oocysts were released only during oviposition. The parasitic development stopped at the gamont stage when oocysts were ingested by late 4th instars (6 days old). The release of sporozoites in the midgut of any larval stage started within 45 min of oocyst ingestion. About 98% of oocysts of both A. taiwanensis and A. culicis were emptied within 2-3 h of their ingestion in their respective hosts. The oocysts of both species remained viable on desiccated filter paper stored at 27 degrees C and 65 +/- 5% relative humidity, indicating that the oocysts were resistant to dryness. The oocysts of A. culicis could survive up to 6 months, whereas those of A. taiwanensis survived up to 4 months. These biological characteristics relating to parasite development might enhance the distribution of Ascogregarina spp. widely in nature and facilitate the species to be considered for biological control of Aedes mosquitoes in the future.
分别用台湾阿氏簇虫和库蚊阿氏簇虫感染埃及伊蚊和白纹伊蚊不同龄期的幼虫，结果显示阿氏簇虫属的卵囊能够感染任何龄期幼虫，并能在9.5±1天内完成其生命周期。当低龄幼虫摄取卵囊时，寄生虫发育与幼虫-蛹蜕皮同步，卵囊在成虫羽化、产卵时或两者同时发生时传播。当感染2龄、3龄和4龄初期幼虫时，寄生虫也能正常发育，且卵囊仅在产卵时释放。当4龄末期（6日龄）幼虫摄取卵囊时，寄生虫发育在配子体阶段停止。在任何幼虫阶段的中肠内，卵囊摄取后45分钟内开始释放子孢子。台湾阿氏簇虫和库蚊阿氏簇虫约98%的卵囊在各自宿主体内摄取后2 - 3小时内排空。两种卵囊在27摄氏度、相对湿度65±5%的干燥滤纸上仍保持活力，表明卵囊对干燥具有抗性。库蚊阿氏簇虫的卵囊可存活长达6个月，而台湾阿氏簇虫的卵囊可存活长达4个月。这些与寄生虫发育相关的生物学特性可能会促进阿氏簇虫属在自然界中的广泛分布，并便于该物种在未来被考虑用于埃及伊蚊的生物防治。
