Reproduction of the large fruit-eating bat Artibeus lituratus (Chiroptera: Phyllostomidae) in a Brazilian Atlantic forest area

Abstract

In this study we investigated the male testicular activity and the reproductive condition of females in relation to their external reproductive characteristics (pregnant, lactating, post-lactating) in the phyllostomid bat Artibeus lituratus (Olfers, 1818). Five hundred and twenty six individuals were examined (197 males and 329 females) in the period December 2001 to May 2003. Throughout the study most males displayed large scrotal testes. Thirty-three males were randomly selected for histological examination at various times throughout the year and were found to have spermatogenic testes. The reproductive characteristics of the females indicated that they were reproductively active mainly during the wet season. Pregnancy occurs at the end of the dry season and parturition in the wet season. Most individuals captured after this season, mainly the females, were sexually immature. Our results suggest a seasonal monoestrous reproductive pattern for the species; however, adult males being fertile throughout the year could suggest polyoestry. Seasonal polyoestry is a possibility. There was, however, no evidence that females had more than one pregnancy per year.

Annual male reproductive activity and stages of the seminiferous epithelium cycle of the large fruit-eating Artibeus lituratus (Chiroptera: Phyllostomidae)

“…testis and epididymis masses, seminiferous tubule diameter, and diameter of Leydig cell nucleus changed significantly between the rainy and the dry seasons. This confirms that continuous spermatogenic activity is taking place, as first described by DUARTE & TALAMONI (2010) for this species in the Atlantic Forest, Southeastern Brazil. The cauda epididymis packed with spermatozoa throughout the study period was also evidence of male continuous reproductive capacity.…”

“…The bats were captured monthly on two consecutive nights from December 2001 to January 2003, using mist nets left in the forest from 18:00 to 24:00 h, following the procedures described in DUARTE & TALAMONI (2010). Thirty-three adult males were captured and killed with an overdose of ether followed by cervical dislocation.…”

“…Based on analysis of seasonal testis activity in Southeastern Brazil, OLIVEIRA et al (2009) reported that the reproductive period of this bat coincides with the rainy season, and is followed by testicular regression before a new cycle of testicular recrudescence. However, in other studies, males have been considered fertile year-round, since they exhibit continuous spermatogenesis (TAMSITT & VALDIVIESO 1963, DUARTE & TALAMONI 2010.…”

Reproductive biology of the bat Sturnira lilium (Chiroptera, Phyllostomidae) in the Atlantic Forest of Rio de Janeiro, southeastern Brazil

“…However, the most common pattern is a response to local climate, as observed in Artibeus lituratus Olfers, 1818, which varies from bimodal polyestrous in Central America (Fleming et al, 1972) and at low altitudes in southeastern Brazil (Reis, 1989) to seasonal monoestrous at altitudes above 1,000 m a.s.l. in southeastern Brazil (Duarte and Talamoni, 2010). Bimodal polyestry was also observed in Platyrrhinus lineatus E. Geoffroy, 1810 at the same latitude of the present study (Costa et al, 2007) and in other species in tropical areas (Fleming et al, 1972;Wilson, 1979;Willig, 1985;Granham, 1989;Stoner, 2001;Estrada and Coates-Estrada, 2001).…”

Reproductive pattern of the large fruit-eating bat, Artibeus amplus (Chiroptera: Phyllostomidae) in the Venezuelan Andes

“…However, it is well known that variations may exist due to specific climatic conditions at each study site (Wilson, 1979;Racey, 1982;Bronson, 1985;Estrada & Coates-Estrada, 2001). For example, monoestrous patterns have been observed in commonly "polyestrous" species, such as A. lituratus in Southeast Brazil (Duarte & Talamoni, 2010), an area characterized by a single maximum rainfall period.…”