Seasonal influence on testicular morphophysiological parameters of bat Carollia perspicillata in fragments of the Atlantic Forest, northeastern Brazil

Abstract

ISSN 0100-736X (Print) ISSN 1678-5150 (Online) RESUMO.-[Influência sazonal sobre os parâmetros morfofisiológicos testiculares de Carollia perspicillata (Chiroptera: Phyllostomidae) em fragmentos florestais de Mata Atlântica, Nordeste do Brasil.] Os morcegos pertencem a ordem Chiroptera, família Phyllostomidae, e apresentam ampla diversidade de estratégias reprodutivas.Entretanto, as informações relacionadas à biologia reprodutiva dos machos são escassas, principalmente no Nordeste do Brasil. Dessa forma, o trabalho avaliou a histomorfometria sazonal testicular de Carollia perspicillata em fragmentos de Mata Atlântica de Pernambuco. Para tanto, os machos adultos foram coletados, eutanasiados para a remoção dos testículos, e posteriormente submetidos à técnica histológica de rotina. As análises histomorfométricas avaliaram as áreas de ocupação do compartimento tubular e intertubular, assim como a quantificação dos espermatócitos, espermátides arredondadas, espermátides alongadas, células de Sertoli e de Leydig. Os resultados indicaram que a espécie apresenta sazonalidade reprodutiva, visto que maiores médias significativas dos parâmetros testiculares foram encontradas na estação chuvosa, que é um período de maior disponibilidade de recursos alimentares. Tais ABSTRACT.-Arandas M.Bats belong to the order Chiroptera, family Phyllostomidae, and present a wide diversity of reproductive strategies. However, information on the reproductive biology of male bats is scarce, mainly in the Northeast Region of Brazil. Thus, this study evaluated the seasonal testicular histomorphometry of the bat Carollia perspicillata in fragments of the Atlantic Forest in Pernambuco state. To this end, adult males were collected, euthanized for removal of the testicles, and later submitted to a routine histological technique. Histomorphometric analysis included assessment of the areas of tubular and intertubular compartment occupation, as well as quantification of spermatocytes, rounded spermatids, elongated spermatids, and Sertoli and Leydig cells. Results indicated that this bat species presents reproductive seasonality, because significantly higher averages of the testicular parameters were observed in the rainy season, which is a period of greater availability of food resources. Such inferences indicate that there is a synchrony between peak spermatogenesis and hormonal inversion in the months of high precipitation; furthermore, a higher carrying capacity of the Sertoli cells is noted. C. perspicillata males possibly present greater sperm and androgenic activity in the rainy season, associated with increased tubular area and number of spermatogenic cells, as well as with the intertubular area and number of Leydig cells, respectively.