Histological Study of the Male Internal Genital Tract of Dwarf Caiman (Paleosuchus palpebrosus Cuvier, 1807)

Brazil has six species of crocodiles belonging to the subfamily Caimaninae,one of them being Paleosuchus palpebrosus (Cuvier, 1807) (dwarf caiman).It is considered one of the smallest crocodilian species, and is sensitive toenvironmental changes. The anatomical and histological descriptions ofthe reproductive tract of reptiles are scarce, so it is important to study themorphology of the genital tract of caimans for a better understanding of thereproduction of these species. We performed the histological analysis of thetestis, epididymis, and deferent duct of the dwarf caiman Paleosuchus palpebrosus. Structures of the genital tract were collected from euthanized animals. Testes, epididymis, and deferent ducts were separated and preparedaccording to routine histological techniques for morphological characterization. The testis is covered by a capsule of fibromuscular connective tissue.Spermatogonia are observed as spherical cells with round nuclei and loosechromatin, and primary spermatocytes show dark cytoplasm, round nuclei,and pale chromatin. Spermatids are seen as cylindrical or filamentous cellswith nuclei that may be highly condensed, ranging from round to oval. Theepididymis is observed as a coiled duct lined by a tall cuboidal epitheliumwith stereocilia; the deferent duct shows ciliated pseudostratified cylindrical epithelium. The adrenal gland is found in the dorsomedial portion of thetestis. The histological structure of the reproductive tract of Paleosuchuspalpebrosus is similar to that of other reptiles’species.

Distribution of the arterial supply to the lower urinary tract in the domestic tom-cat (Felis catus)

This study was aimed at determining the arterial supply and gross vascular architecture of the urinary bladder in the male cat. For this purpose, the urinary bladders of 10 cats were evaluated. Organ vascularization was investigated using the latex injection technique. The feline urinary bladder was found to be supplied by the prostatic artery, which stemmed from the internal pudendal artery and the umbilical artery that originated from the internal iliac artery. The umbilical artery extended caudally to form the cranial vesical artery, which was later distributed into the corpus and apex of the urinary bladder. The feline prostatic artery divided into the artery of the deferent duct and a slim branch, which supplied the prostate gland. The artery of the deferent duct gave off a caudal vesical artery which gave off slim branches to the preprostatic urethra. On the surfaces of the urinary bladders examined, the cranial and caudal vesical arteries followed varying courses, which reflected individual variations. In all samples, the blood vessels generally divided into two or three branches on the surface of the urinary bladder, whilst in only one sample, the caudal vesical artery was observed to be of the ladder type. Moreover, the cranial and caudal vesical arteries anastomosed with each other on the surface of the urinary bladder. This study constitutes a model for comparison with other species and provides morphological contributions to anatomy training and surgical interventions since there is a lack of literature on species-specific vascular morphology in the field of veterinary urology in contrast to the abundance of studies on humans and rodents.