苯醚威作用于不等单蚤的组织学研究(蚤目:蚤科)

Effect of fenoxycarb on the tissue of Monopsyllus anisus (Siphonaptera:Pulicidae)

目的通过研究苯醚威对不等单蚤的早3龄幼虫和未吸血新羽化成虫的组织学变化,探讨其灭蚤机制,为鼠疫媒介蚤种的防治提供基础资料。方法用微量点滴法将苯醚威施药于不等单蚤早3龄幼虫和未吸血新羽化成虫,采用组织学、显微摄影及统计学方法观察组织变化。结果经苯醚威作用后,不等单蚤早3龄幼虫的表皮增厚,卵巢芽先增大后缩小,睾丸芽缩小,中肠上皮细胞萎缩;不等单蚤未吸血新羽化成虫的睾丸塞消失快,唾液腺细胞破坏,中肠上皮细胞萎缩。结论(1)苯醚威通过干扰不等单蚤幼虫的变态,引起幼虫表皮、生殖芽和中肠上皮细胞异常改变,未能发育为成虫而死亡。(2)苯醚威可加速不等单蚤新羽化雄性成虫的睾丸塞吸收。(3)苯醚威可破坏不等单蚤新羽化成虫的唾液腺细胞,并引起中肠上皮细胞萎缩。

Objective To provide the fundamental data for the control of the flea and to explore insecticidal mechanisms of fenoxycarb to the early third-instar larvae and the newly emerged adults of Monopsyllus anisus （Rothschild, 1907） through histological observations. Methods The early third instar larvae and the newly emerged adults of M.anisus were treated with fenoxycarb by microliter syringes. The changes of tissues were determined by the methods of histology, microphotographics and statistics. Results The cuticula of the third instar larvae of M.anisus treated with fenoxycarb became thicker, the ovarial rudiments augmented firstly then shrank. The testicular rudiments shrank, and the midgut epithelial cells became atrophy. The testicular plug of the newly emerged adults of M.anisus treated with fenoxycarb disappeared fast, the salivary gland cells were damaged, and the midgut epithelial cells became atrophy. Conclusion （1）Fenoxycarb can cause the death of M.anisus larvae by the disturbance of larvae metamorphosis and changes in cuticula, ovarial rudiments and testicular rudiments or midgut epithelial cells. （2）Fenoxycarb can accelerate the disappearance of testicular plug of the newly emerged male adults. （3）Fenoxycarb can lead to the death of the newly emerged adults of M.anisus by the damage of salivary gland cells and atrophy of midgut epithelial cells.