Histopathological study of ovaries of Rhipicephalus sanguineus (Acari: Ixodidae) exposed to different thymol concentrations
Nenhuma Miniatura disponível
Data
2014-12-01
Autores
Matos, Renata da Silva
Daemon, Erik
Camargo-Mathias, Maria Izabel [UNESP]
Scopinho Furquim, Karim Christina [UNESP]
Sampieri, Bruno Rodrigues [UNESP]
Remedio, Rafael Neodini [UNESP]
Araujo, Laryssa Xavier
Lopes Novato, Tatiane Pinheiro
Título da Revista
ISSN da Revista
Título de Volume
Editor
Springer
Resumo
Thymol is a monoterpene with proven acaricide action for several tick species. In addition to killing these ectoparasites, thymol can also reduce oviposition and egg hatch rate. However, the effects of thymol on the morphophysiology of tick ovaries are still unknown. Thus, the aim of this study was to evaluate the morphophysiological changes caused by this active principle in ovaries of Rhipicephalus sanguineus after a 6-day feeding period, through the application of morphohistochemical techniques. After the feeding period, a total of 50 females were divided into five groups and immersed in the following solutions: (I) distilled water (control), (II) 30 % ethanol (control), (III) 1.25 mg/mL thymol, (IV) 2.5 mg/mL thymol, and (V) 5.0 mg/mL thymol. The experimental groups were kept in a climatic chamber (27 +/- 1 A degrees C; RH 80 A +/- 10 %) for 5 days. After this period, morphological (hematoxylin/eosin) and histochemical (von Kossa) techniques were applied after remotion of the ovaries. The morphological results revealed large vacuoles in germ cells at different developmental stages and invaginations that represent deformations in the chorionic membrane. From the results obtained in this study, it was concluded that thymol interfered with the development of oocytes, which showed degeneration signs. The treatment containing 5.0 mg/mL thymol affected more accentuately the morphological development. Moreover, thymol also altered the calcium content of yolk granules, which generally showed an intense staining for this element.
Descrição
Palavras-chave
Histology, Histochemistry, Brown dog tick, Monoterpene
Como citar
Parasitology Research. New York: Springer, v. 113, n. 12, p. 4555-4565, 2014.