Search

Simple Summary: Sugar gliders are exotic animals that have become pets in recent years. As a result, these small marsupials are increasingly coming to the veterinary practices. Marsupials are a group of mammals characterized by their peculiar way of reproduction. This translates into the distinct anatomy of their genital apparatus, both male and female. There are not many references concerning the anatomy of this particular species. The male reproductive system of the Petaurus breviceps follows the general pattern in marsupials, but each species has its own peculiarities that the veterinary clinician should know. It includes two testes, epididymis, and deferent ducts, as well as two types of accessory glands: the prostate and the bulbourethral glands, in addition to the male urethra and the penis, which is bifid at its end. The purpose of this study was to describe the male genital gross anatomy of the sugar gliders (supplemented with some microscopic observations), to provide detailed information to veterinary clinicians to facilitate accurate diagnosis and surgery. The present study provides a detailed macroscopic examination (with some microscopic insights) of the genital apparatus of seven adult and intact male sugar gliders, as well as one castrated individual. The scrotum is pendulous and attached to the ventral abdominal wall, situated in the caudal part of the abdomen and cranial to the cloacal opening. The testes are oval shaped with their long axes oriented vertically. The epididymides are attached along the caudomedial border of their respective testes. The head and tail of the epididymides are in close proximity to the poles of the testes but are not directly attached. The deferent ducts are positioned laterally to their ipsilateral ureter as they run near the dorsal surface of the urinary bladder. The ampulla of the deferent duct is absent. The penis is located post-scrotally, lacks insertion into the bony pelvis, and has a bifid distal end. The crura of the penis originate within the ischiocavernosus muscles, and there are two bulbs of the penis. When flaccid, the entire penis is concealed in the perineal region and externalizes through an orifice situated in the ventral part of the cloaca, traversing its floor towards the cloacal opening. The urethral external orifice is positioned at the point where the bifurcation of the free part of the penis begins. The prostate gland resides in the pelvic cavity and consists of two parts: a macroscopically visible body surrounding the urethra and a microscopically identifiable portion embedded within the walls of the duct. Sugar gliders possess two pairs of bulbous bulbourethral glands, located dorsally and laterally to the rectum, but lack vesicular glands. [ABSTRACT FROM AUTHOR]

Simple Summary: The developmental anatomy of the dolphin head has been studied mostly in single fetuses and few works have been made using a wide range of specimens. In this study, fetal specimens are the main subjects, but newborn, juvenile and adult specimens were also used. Our study analyzes the external nose and nasal cavities during pre- and postnatal development. The nose and nasal cavities were studied using a high-resolution endoscopy to analyze changes in the mucosa of fetal specimens, newborns and juveniles. Magnetic Resonance Imaging (MRI) was also used in fetuses to locate and identify significant structures. Computed Tomography (CT) allowed us to understand the development of the facial bones and the nasal cavity. The histological samples were compared with a horse, a terrestrial mammal with a complex nasal anatomy. Dissections and anatomical sections in two spatial planes were compared with MRI and CT studies. Endoscopy of the external nose showed interesting morphological changes as only two different diverticula (air sacs) were observed in the vestibular part and one recess in the respiratory and olfactory part. We conclude that nasal cavity development of the striped and common dolphins and the pilot whale is simpler than in the bottlenose dolphin and the melon is part of the nose both anatomically and functionally. Our goal was to analyze the main anatomical structures of the dolphin external nose and nasal cavity from fetal developmental stages to adult. Endoscopy was used to study the common development of the external nose and the melon, and nasal mucosa. Magnetic resonance imaging (MRI) and anatomical sections were correlated with anatomical sections. Computed tomography (CT) was used to generate 3D reconstructions of the nasal bones and nasal cavities to study its development. Dissections, histological and pathological studies were carried out on the nasal mucosa to understand its function. These results were compared with the horse. Endoscopy showed an external nose with two lips and the upper lip is divided by a groove due to the nasal septum and an obstruction of right nasal cavity was diagnosed in a newborn. Two diverticula (air sacs) were found in the nasal vestibule and an incisive recess (premaxillary sac) in the nasal cavity. These findings were corroborated by 3D reconstructions of the nasal cavities, MRI, anatomical sections and dissections. The presphenoid and ethmoid bones were fused at early stages of fetal development. The ethmoid is the last bone to ossify in the nasal cavity. [ABSTRACT FROM AUTHOR]

Reeler mutant mice lack Reelin, a neuronal glycoprotein, that plays a crucial role in brain development. They have low body weight and most of them are sterile. Since the brain plays a key role in the regulation of pituitary function and structure, we decided to study the pituitary in the reeler mutant mice. All mice were handled in accordance with the procedures of the Guiding Principles for the Care and Use of Animal Research (86/609/EU). Mice were divided into 3 groups of 5 mice each: Reeler Homozygotes (RHM), Reeler Heterozygotes (RHT) and Controls (CO). Animals were weighted and sacrificed with pentothal anesthesia. Blood hormones levels were measured by RIA. Pituitaries were removed, weighted and paraffin embedded for histology and immunohistochemistry or Epon embedded for electron microscopy. Body and pituitary weights were decreased in RHM and RHT mice. Blood Growth Hormone (GH) levels were not reduced and no major changes were detected in the blood levels of other pituitary hormones. Histological, immunohistochemical and ultrastructural studies revealed no differences in pituitary cells between RHM, RHT and CO except that somatotrophs seemed to be slightly smaller in RHM and RHT. In conclusion, no major alteration indicating pituitary hypofunction was demonstrated in reeler mice. More studies are needed to reveal the cause of their low body weight and infertility. [ABSTRACT FROM AUTHOR]

The present study provides a detailed macroscopic examination (with some microscopic insights) of the genital apparatus of seven adult and intact male sugar gliders, as well as one castrated individual. The scrotum is pendulous and attached to the ventral abdominal wall, situated in the caudal part of the abdomen and cranial to the cloacal opening. The testes are oval shaped with their long axes oriented vertically. The epididymides are attached along the caudomedial border of their respective testes. The head and tail of the epididymides are in close proximity to the poles of the testes but are not directly attached. The deferent ducts are positioned laterally to their ipsilateral ureter as they run near the dorsal surface of the urinary bladder. The ampulla of the deferent duct is absent. The penis is located post-scrotally, lacks insertion into the bony pelvis, and has a bifid distal end. The crura of the penis originate within the ischiocavernosus muscles, and there are two bulbs of the penis. When flaccid, the entire penis is concealed in the perineal region and externalizes through an orifice situated in the ventral part of the cloaca, traversing its floor towards the cloacal opening. The urethral external orifice is positioned at the point where the bifurcation of the free part of the penis begins. The prostate gland resides in the pelvic cavity and consists of two parts: a macroscopically visible body surrounding the urethra and a microscopically identifiable portion embedded within the walls of the duct. Sugar gliders possess two pairs of bulbous bulbourethral glands, located dorsally and laterally to the rectum, but lack vesicular glands.