Efeito dos fungicidas Mancozeb e Tebuconazol sobre parâmetros testiculares do morcego frugívoro Artibeus lituratus (Olfers, 1818)

• Autor(a) principal: Miranda, Diane da Cruz
• Data de Publicação: 2012
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/2349
• topic: Agrotóxicos; Histomorfometria; Túbulos seminíferos; Células de Leydig; Pesticides; Histomorfometry; Seminiferous tubules; Leydig cells; CNPQ::CIENCIAS BIOLOGICAS::BIOLOGIA GERAL

Due to destruction of their natural habitat, fruit bats are feeding on fruits obtained from orchards sprayed with fungicides. Once these animals act in maintaining the ecosystem and the regeneration of degraded environments, the effect of pesticides on them can endanger not only their survival and adaptation, but also the maintenance of forests. Thus, as no studies were found assessing the impact of ingestion of these substances on testicular morphophysiology in these animals, the objective of this study was to analyze some testicular parameters in Artibeus lituratus (n = 28) after acute and/or chronic exposure to fungicides Mancozeb e Tebuconazole. The animals were divided into five groups: control group 1 (G1, n = 5), in which animals were fed with fruits without fungicides and without adjuvant (AD) for seven days, control 2 (G2, n = 5), animals fed with fruit + AD for seven days, and other three groups containing animals fed fruits with Mancozeb + AD (G3, n = 6; 2g/L) and Tebuconazole + AD (G4, n = 6; 1 mL/L) for seven days and Tebuconazole + AD(G6, n = 6) for 30 days. After euthanasia, the animals were weighed, and their testes were dissected and fixed (Karnovsky solution) to be processed and enclosed in resin. Histological sections (3μm) were stained and evaluated concerning the following parameters in a light microscope and Image Pro Plus software: diameter and length of seminiferous tubules, seminiferous epithelium height, proportion and volume of tubule and intertubule components, Leydig cell morphometry, and gonadosomatic, tubulossomatic and leydigossomatic indexes. After submitting the results to statistical analysis (ANOVA), comparing the means by Newman-Keuls test (p = 0.05), we observed that exposure for seven days to two fungicides caused no testicular morphological changes when compared to controls, showing that the substances have low acute toxicity. Conversely, animals chronically exposed to Tebuconazole (30 days) showed decrease in the percentage of seminiferous tubules per testicular parenchyma, which coincided with increase in the percentage of intertubule (for testicular parenchyma), decreased in the percentage of seminiferous epithelium and lower values for tubule diameter and tubulossomatic index when compared to control groups. In the intertubule there was a greater proportion of blood vessels and a lower percentage of lymphatic space. In addition, the Leydig cells showed morphometric changes such as reduction in their proportion of cytoplasm (in the intertubule), in nuclear diameter, in nuclear volume and cytoplasmatic and cell volume, and increased number of these cells per gram of testis. It can be concluded that in the concentrations established for use in the field and tested in this study, Mancozeb and Tebuconazole did not cause testicular changes when the exposure is acute. However, chronic exposure to Tebuconazole causes histomorphometric changes at the level of testicular seminiferous tubules, intertubule and Leydig cells.