Avaliação morfofuncional do testículo e do processo espermatogênico do periquitão-maracanã (Aratinga leucophthalma MULLER, 1776) adulto, mantido em cativeiro, nas diferentes estações do ano

• Autor(a) principal: Peixoto, Juliano Vogas
• Data de Publicação: 2006
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/5113
• topic: Aratinga leucophthalma; Testículo; Sazonalidade; Espermatogênese; Aratinga leucophthalma; Testis; Seasonality; Spermatogenesis; CNPQ::CIENCIAS BIOLOGICAS::MORFOLOGIA

For this experiment it was utilized testicles fragments from 14 adults White-Eyed Parakeet (Aratinga leucophthalma), proceeding from the Centro de Triagem de Animais Silvestres - Universidade Federal de Viçosa, Minas Gerais, Brazil. The fragments were evaluated for seasonal reproductive activities using the following parameters: average thickness of testicular tunica albuginea, volumetric proportion of tubular and extratubular compartment, average diameter of the seminiferous tubules, and in addition the average of corporal weight. For this experiment the animals were distributed into four groups and had collected testicular fragments on the following dates: February 6, 2006, May 11, 2006, August 16, 2006 and November 7, 2006. These dates corresponded to the seasons of Summer, Fall, Winter and Spring respectively. The animals were submitted to general anesthesia, using a volatile gas, and a incisional biopsy was made using celioscopy. The fragments collected were processed histologically, the slides were prepared and later evaluated using an optical microscope. The average seasonal values of body weight increased starting at the Winter and reaching the peak during the Spring. A seasonal testicle cycle was observed in Aratinga leucophthalma, since increased significant values of volumetric proportion of seminiferous tubules, average diameter of the seminiferous tubules and degree of spermatogenic development were observed during the Spring, in contrast with the minimum values of these same parameters observed during the Fall. Furthermore, the average thickness of the testicular tunica albuginea was significantly greater during the Fall, showing a significant and gradual decrease of the values during the Spring. The evaluated parameters of spermatic production in Aratinga leucophthalma, during the different seasons, showed strong positive correlations with the average daily light (p<0,1) and strong negative correlation with the relative air humidity (p<0,1). In conclusion, during the Spring the testicles of the Aratinga leucophthalma show the values of the quantitative parameters of spermatic production, compatible with the period of greater activity, the opposite happening during the Fall.