[Histopathological effects of neem products on larvae of Culex quinquefasciatus (Say, 1823) (Diptera: Culicidae)].

Introduction: Histopathological studies relating to last instars larvae of mosquitoes treated with neem products are very few. The objective were to study the action of Neem products on larvae mosquitoes of Culex quinquefasciatus.

Materials and methods: The neem products (Neemix, Formulated neem oil, Pure neem oil and Neem powder) are tested on 4 instars larvae of Culex quinquefasciatus. Moribund and witness larvae were fixed, for histopathologic study.

Results: The results showed the following facts: an intestinal epithelium, a bross border, a fat body and others tissues are normals at the level of the untreated larva; Fat body and muscle are not touched during the treatment of the larva with Pure neem oil; Intestinal epithelial cells slightly hypertrophied with beaches of lysis on the level of the larva treated with Neem powder; a lysis of the microvilli of brush border on the level of the witness-solvent; a destruction of the epithelial cells recorded in larva treated with a Neemix; a disappearance of the food column and a destruction of the epithelial cells remarked on the level of the larva treated with Formulated neem oil.

Conclusion: The neem products used in this study have a Larvaecidal action on Culex quinquefasciatus larvae.