Anatomy and histology of the prostate and glands of Cowper in three species of neotropical bats

Abstract

The reproductive accessory glands (RAG) are essential components in reproduction because their secretion products ensure survival, viability, and sperm motility. The objective of this study was to characterize and compare the morphological and histological structure of the RAG in three species of bats of the genus Sturnira (S. erythromos, S. lilium, and S. oporaphilum). The RAG complex comprise a compact gland (prostate), which surrounds the urethra, and a pair of Glands of Cowper at the base of penis. Anatomical and histologically, the prostate are differentiated in two regions, ventral and dorsal. The dorsal region has tubuloalveolar glands with secretions fine granular or accumulations of a gel-like substance with bubbles and the ventral region, has alveolar glands with secretory cells form a single-layer of small cells. The seminal vesicles are absent. The prostatic morphology of the three species is similar to that of other studied Stenodermatinae and Desmodontinae, but differs from other subfamilies of Phyllostomidae (Carollinae, Glossophaginae, and Phyllostominae) as that of Molossidae and Vespertilionidae. The RAG complex has no annual variation in relation to functionality or size, but it is variable depending on age (subadults and adults). This agrees with the annual reproductive pattern described for these species in these latitudes, where adult males are reproductively active throughout the year.

The prostate of the bat Artibeus lituratus: Seasonal variations, abiotic regulation, and hormonal control

“…Phyllostomid bats also present a compact prostate; however, it varies from two regions (ventral and dorsal), in Stenodermatinae (Martins et al, 2015;Miotti et al, 2018;Puga et al, 2013;Santos et al, 2018) and Desmodontinae (Martins et al, 2015), to three regions (ventral, dorsal, and dorsolateral), in species of Carollinae, Glossophaginae, and Phyllostominae subfamilies (Martins et al, 2015(Martins et al, , 2016.…”

“…Despite the central role of the prostate in reproductive function and the wide morphological variation, little attention has been given to this organ in bats. The few existing studies on bat prostate generally focus on the description of its composition and morphology (Beguelini et al, 2016;Martins et al, 2015Martins et al, , 2016Miotti et al, 2018;Puga et al, 2013;Santos et al, 2018), with only one or two studies, investigating effects of hormonal and abiotic factors (Christante et al, 2015;Negrin et al, 2014;Puga et al, 2014). In addition, even these few studies tend to investigate only the regulation of a single hormone, in addition to presenting an unrepresentative sample design, by dividing their specimens in dry and rainy seasons, or by seasons (spring, summer, etc.…”

Sperm morphology and comparison morphometry measurements of two species of bats, Molossus molossus and Molossops temminckii (Chiroptera: Molossidae)

“…Compared to females, the reproductive system of males and their reproductive cycles have been understudied, assuming that they are directly in synchrony with the female's cycle. Thus, the reproductive patterns and some processes such as spermatogenesis and the study of sperm morphology have been described in very few taxa (Beguelini et al, 2009; Miotti, 2020; Miotti et al, 2018).…”

“…The variability in latitude, temperature, rainfall and photoperiod have an effect on the reproductive strategies of the different species of bats (Fleming et al, 1972), presenting exclusive characteristics such as testicular regression, sperm storage in both sexes, asynchrony between spermatogenesis and copulation, delayed ovulation, fertilization, implantation, and development (Beguelini et al, 2009, 2011). They also present great morphological diversity in terms of their reproductive tracts, attached glands and sperm morphology (Beguelini et al, 2013; Miotti, 2020; Miotti et al, 2018).…”

Three-Dimensional and Histological Observations on Male Genital Organs of Greater Horseshoe Bat, Rhinolophus ferrumequinum

“…The mammalian male reproductive organs comprise paired testes, epididymis, and accessory genital glands, with the testis, epididymis, and accessory genital glands exhibiting variation in shape and position (Miotti et al 2018;Santos et al 2018). Four types of testes locations (permanently abdominal, permanently scrotal, migratory, and external) are described, which do not necessarily reflect phylogenetic relationships (Table 1).…”