Revista Brasileira de Zootecnia
versão On-line ISSN 1806-9290
AMOROSO, Lizandra et al. Spermatogenesis and testosterone levels influence on reproductive aspects of Japanese quails. R. Bras. Zootec. [online]. 2008, vol.37, n.1, pp. 61-66. ISSN 1806-9290. http://dx.doi.org/10.1590/S1516-35982008000100008.
Testosterone levels to the body weight, relative and absolute testes weights, tunica albuginea thickness, germinative epithelium height, diameter and meiosis picture numbers of seminiferous tubules of 65 male quails were evaluated from June to October. The birds were grouped in cages (6 birds/cage) and lodged in a shed during all experimental period. The testis morphometric analysis was carried out from 60 days to 180 days old. The total testosterone plasmatic levels were dosed by radioimmunoassay method with antibody radioactivity marked. The morphometric analysis result showed that testosterone concentrations influenced the bird testis germinal epithelium behavior, with maximum spermatogenic activity during the period of 110 to 130 days old, that demonstrate the phase of mayor reproductive activity coincided with the crescent photoperiod beginning, that is, in the end of August up to September beginning. The testosterone peak was prior to maximum spermatogenesis, to evidence the reproductive system preparation for proliferative phases. At 180 days old, still submitted to long days in October, the birds presented low circulate testosterone levels and testicular parameters regression.
Palavras-chave : Coturnix coturnix japonica; gametogenesis; steroid hormone; morphometry; reproduction; testis.