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ABSTRACT: This study performed a histomorphometric analysis of the retina and estimated the visual acuity of three fruit-eating bats of the genus Artibeus, including Artibeus lituratus, Artibeus planirostris and Artibeus obscurus. In total, 13 animals were used for this study, in which the retinas were hemidisected, fixed, cut, and stained. The visual acuity was determined by the density of ganglion cells in the retina and the retinal layers were also measured from histological sections. The retinas of these bats are avascular, do not present tapetum lucidum in any quadrant, and have the 10 retinal layers common in mammals. Moreover, it was observed that the thickness of the retina in the central region was significantly higher in all measured parameters (p

Resumo: Esse estudo objetivou avaliar o efeito da ooforectomia sob os parâmetros histomorfométricos dos cardiomiócitos e quantificação de colágeno em ratas Wistar. Vinte ratas foram utilizadas e separadas em dois grupos: GI - ooforectomizada e GII - sham-ooforectomizada. Após a recuperação anestésica os animais foram acomodados em gaiolas e separados nas condições de ciclo claro/escuro 12/12h por um período de 6 meses. Passado o período experimental, os animais foram anestesiados, o coração retirado e mergulhado em formaldeído a 10%. Os fragmentos dos ventrículos foram submetidos ao processamento histológico e corados com hematoxilina e eosina. As análises histomorfométricas (área celular e área e volume nuclear) foram realizadas pelo microscópio de luz e software ImageJ versão 1.44. Os dados foram submetidos à análise ANOVA e quando significantes, complementados pelo teste t de student (p

ABSTRACT: 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.

ABSTRACT: This study aimed to analyze the reproductive stage, histology and morphometry of the ovary of Dermanura cinerea in an Atlantic Forest fragments in the Biological Reserve of Saltinho, Pernambuco, Brazil. Adult females were captured monthly by mist net, during two consecutive nights from June/2014 to November/2015. The meteorological data were provided by the National Institute of Meteorology and grouped together with the reproductive data, in six periods: period I (June to August/2014), period II (September to November/2014), period III (December/2014 to February/2015), period IV (March to May/2015), period V (June to August/2015) and period VI (September to November/2015). The females were classified according to their reproductive stages in: Inactive, pregnant, lactating and postlactating. Among the 25 females caught, 10 inactive females were selected for the histomorphometric analysis of the ovaries and then they were euthanized. After that, the specimens had their ovaries removed, fixed, processed and included in Paraplast. The organs were cut and stained by Hematoxylin - Eosin and the histological slides produced were submitted to the appropriate optical microscope analysis. Each type of ovarian follicle was estimated according to the histological characteristics evidenced for other mammals. In the morphometric analysis, it was considered: The area of the ovary (measured in square millimeter), Quantification of different types of ovarian follicles (unilaminar and multilaminar primary follicles, antral and matures) and corpus luteum, as well as the area of each by those different follicles (measured in square micrometer) The results indicated that 16 females were inactive, 5 were lactating, 4 were pregnant and no post-lactating. The histological analysis revealed that the ovaries of D. cinerea exhibit characteristics, structures and cellular types similar to other mammals. The morphometric data of the study area were statistically evaluated using the Student’s t-test. Therefore, ovarian histomorphometric analysis are very important to infer with greater certainty about the reproduction of a species. Thus, it was observed that females of D. cinerea exhibit two reproductive peaks, that is, they can give birth either at the end of dry periods or from the beginning to the middle of the rainy season. The main feature observed in the ovary of this species, found in the Atlantic Forest area of the state of Pernambuco, is the preparation of the ovarian cortex to ovulate in months of high rainfall throughout the year. Therefore, this species tries to adjust its reproductive period with the variations of the environmental conditions, so that the reproduction might occur during the period more favorable for the maintenance of their offspring.