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This study aimed to conduct a morphoquantitative and stereological evaluation, analyzing the cerebellum of domestic cat fetuses in the latter third of the gestational period. Fetal samples were obtained from a neutering campaign conducted in the municipality of Guarulhos, São Paulo, Brazil. The procedures and protocols used in this work adhere to the guidelines established by the ethics committee of the School of Veterinary Medicine and Animal Science at the University of São Paulo (FMVZ/USP), under the number CEUA 1935251121. The five selected fetuses were fixed in 4 % formaldehyde, and their gestational age was determined by Crown Rump (CR) measurements, followed by an assessment of external characteristics. The cerebella were subjected to the evaluation of morphometric parameters and histological processing using stereology techniques. The obtained means for the cerebellar parameters were as follows: length: 1.0-centimeter, width: 0.54 centimeters, thickness: 0.44 centimeters, and weight: 0.84 g. Using stereology, the following parameters were determined: cerebellar volume, averaging 0.847 cm³; volume density of the cortex: 0.496 or 49 % (molecular layer), 0.0314 or 3.14 % (Purkinje cell layer), 0.232 or 23 % (granular layer), and 0.234 or 23 % (medullary white center). Consequently, the average total volume of the cerebellar cortex is 0.419 cm³ for the molecular layer, 0.026 cm³ for the Purkinje cell layer, 0.196 cm³ for the granular layer, and 0.196 cm³ for the medullary white center. The findings presented here have contributed to an in-depth discussion of the neuro-motor development and cerebellum of domestic cats., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier GmbH. All rights reserved.)

Capybara is considered the largest living rodent and is widespread distributed in the South America and in the Brazilian territory. The purpose of this study was to provide the anatomical description of the brain in the capybara (Hydrochoerus hydrochaeris) using magnetic resonance imaging (MRI). Brains of ten normal capybaras were imaged and sectioned in the anatomical studies. MRI was acquired on 0.25 Tesla equipment, promoting good-quality images capable to identify and classify the main anatomical structures of clinical interest. MRI reference images were validated by comparing them with gross anatomical sections. The capybara sulci and gyri were named for its similar location and orientation to those described in the previous descriptions in the capybara and in the domestic dog. Capybaras presented prominent cerebral sulcus and gyrus in relation to other caviomorph rodents, but in reduced number when compared to domestic animals and other wild mammals such as elephants and giraffes. The findings of this study indicate that the shape of the capybara brain is remarkably similar to that of the caviomorph rodents with a higher neocortilization. The capybara rhinencephalon was well-developed implying a good sense of smell. Due to this development of the rhinencephalon, we can suggest that capybara brain is a macrosmatic brain. The MRI and gross anatomical sections of capybara brain may help veterinary researchers and clinicians increase the accuracy of brain MRI scans interpretation in these animals., (© 2024 Wiley‐VCH GmbH. Published by John Wiley & Sons Ltd.)

Maternal protein restriction delays the differentiation of epididymal mesenchymal cells in newborn rats. However, it's unclear if this delay persists until the full differentiation of the epididymal epithelium at 44 days postnatal. Thus, this study aimed to assess the impact of maternal protein reduction on 44-day-old rats' epididymal epithelium differentiation, following up on the observed delay in newborn animals. Pregnant rats were randomly divided into groups receiving normal-protein (NP - 17% protein) or low-protein (LP - 6% protein) diets during gestation and lactation. On postnatal day (PDN) 44, male offspring were euthanized, and the epididymis (NP n=10, LP n=10) was processed according to immunohistochemical techniques for the detection of aquaporin 9 (AQP9), KI-67, TP63, and ATPase. LP rats showed: a decrease in the intensity of the AQP9 reaction, an increase in cellular proliferation in the initial segment and corpus of the epididymis, an increase in basal cells in the caput and corpus epididymis, and an increase in ATPase-positive clear cells in the cauda region. These findings demonstrate that maternal protein restriction impacts cell differentiation in the epididymal epithelium of 44-day-old rats, persisting even with a normal-protein diet after weaning., (© 2024. Published by The Company of Biologists Ltd.)

The present study aimed to determine references of normality of computed tomographic (CT) images of mandibular and parotid salivary glands (PSGs), medial retropharyngeal and mandibular lymph nodes and thyroid gland of 10 clinically healthy crab-eating foxes, Cerdocyon thous. The location, shape, homogeneity of the parenchyma, and length, height, width and pre- and post-contrast attenuation values were evaluated. The anatomical structures in the crab-eating foxes studied here presented anatomical landmarks similar to those described for domestic dogs, and showed a regular shape and homogenous parenchyma, except for the PSGs, that showed predominantly heterogeneous parenchyma. The thyroid gland topography in the crab-eating fox, though very similar, is not identical to the domestic dog and the presence of isthmus between the lobes was not detected. The values obtained from crab-eating foxes are within the normal range, although in the upper limits of dogs. There was a significant difference in the attenuation values between the right and left lobes of the thyroid gland, being greater in the left thyroid lobe. CT attenuation values ranges for this neotropical canid can be incorporated into routine staging procedures in the veterinary care of the crab-eating foxes. Furthermore, the CT images obtained were similar to those of healthy dogs, and the information obtained can be considered as initial tomographic references of normality in the cervical structures of the crab-eating fox, in order to aid in the diagnosis of future diseases that can affect this neotropical canid., (© 2023 Wiley-VCH GmbH. Published by John Wiley & Sons Ltd.)

The white-eared opossum (Didelphis albiventris) is a Neotropical marsupial that occurs in the Brazilian territory. The larynx is an important organ of vocalization in mammals, although, other laryngeal functions are more fundamental for survival of mammals than phonation. The anatomical knowledge of respiratory structures is pivotal for a better understanding of the species. Thus, this study aimed to examine the larynx of the white-eared opossum by gross anatomy, computed tomography and histological description. For this, 10 adult (six females and four males) white-eared opossums (D. albiventris) were used. The white-eared opossum larynx was formed by epiglottis, thyroid, cricoids and arytenoid cartilages and a corniculate process. There is a similarity between the larynx of this marsupial and those reported in other wild mammals, regarding the number of cartilages and their location. Histologically, the epiglottis consisted of elastic cartilage and thyroid, cricoid and arytenoid cartilages were composed of hyaline cartilage. The epiglottis protruded rostrally into the nasal part of the pharynx, above the soft palate, and this is probably a marsupial characteristic as the fact that the thyroid and cricoid cartilages were ventrally fused. The hyoid apparatus was similar to that of other animals, with the same bony constitution, but with a greatly reduced stylohyoid bone. Histologically, the larynx was similar to those of other species such as koala, armadillo, crab-eating foxes and giant anteaters. The knowledge of the larynx morphology is important for the anatomical features of the species and clinical and surgical procedures, such as endotracheal intubation., (© 2023 Wiley-VCH GmbH. Published by John Wiley & Sons Ltd.)

The aim of this study was to describe the morphology of the trachea and syrinx at macroscopic and light microscopy levels of three species of birds from different orders that inhabit the Brazilian cerrado. For that, five adult specimens (three males and two females of each species) of white-eyed parakeet (Psittacara leucophthalmus), red-winged tinamou (Rhynchotus rufescens) and red-legged seriema (Cariama cristata) were used. The trachea and syrinx of the birds were collected and destined for anatomical and histological studies. The trachea of the studied birds presented an elongated path and originated in the larynx and extended caudally to the syrinx. No sexual dimorphism was observed in the syrinx of the studied species, probably because it is associated with their song, which is very similar between males and females of these species. The findings of this study allowed us to classify the syrinx as tracheal in the white-eyed parakeet and tracheobronchial in the red-winged tinamou and red-legged seriema. In general, the morphological features of the trachea and syrinx were similar to those described for other species of birds, such as the presence of intrinsic and extrinsic syringeal muscles, and the lateral and medial tympaniform membranes, which would represent important anatomical structures in sound production through vibration during expiration and eventual inspiration. The morphological structure of the syrinx in the three avian species of the Brazilian cerrado is consistent with the ability of these avian species to perform a potential vocalization, especially the red-legged seriema that emits characteristic sounds very loud and can carry several kilometres., (© 2023 Wiley-VCH GmbH. Published by John Wiley & Sons Ltd.)

The giant anteater (Myrmecophaga tridactyla) is the largest of the Neotropical vermilinguans. This animal is the second mammal most frequently run over on the roads of Cerrado biome, Brazil. Therefore, it is pivotal to know the anatomy of this species to contribute to the clinical care of these animals. Thus, the aim of this study was to identify the anatomical structures in the abdominal region of the giant anteater using computed tomography (CT). For this, the tomographic analysis was performed in sequential order in the craniocaudal direction in five giant anteaters. Moreover, four giant anteater corpses were used for anatomical studies, where two corpses were sectioned in cross sections of approximately 3 cm each, and two animals were dissected to identify the abdominal organs. The association between CT and anatomical study allowed the visualization of anatomical structures found in the abdominal cavity, such as the topographic anatomy facilitates the identification of organs on CT images. The findings of this study demonstrated that CT is a good technique to provide detailed information about the anatomical structures in the abdominal cavity and that this study can be used as CT and anatomical reference for veterinarians who care for wild animals., (© 2022 Wiley-VCH GmbH.)

Capybaras have been victims of collisions against vehicles, which can result in fractures of the teeth and mandible. Then, a local anaesthetic block of the inferior alveolar and mental nerves is important for performing therapeutic procedures in the oral cavity of these rodents. Thus, the aim of this study was to describe the mandibular morphometry of the capybara with emphasis on the establishment of anatomic references for anaesthetic block of the inferior alveolar and mental nerves. For this, mandibles from eight young and adult capybaras were used. Radiography and morphometry of the capybara hemimandible were performed. The mandibular foramen had a dorsoventral diameter of 2.1 mm in young and 2.2 mm in adult capybaras, and it was situated ventrally to the third molar tooth. For extraoral block of the inferior alveolar nerve, the needle should be introduced obliquely 63.5 and 77.4 mm from the angular process in young and adult capybaras, respectively. In another extraoral approach, the needle should be introduced perpendicularly 20.8 mm in young and 26.3 mm in adult animals from the ventral margin of the capybara mandible. For blocking only the mental nerve, the needle should be inserted perpendicularly from the interalveolar margin, 10.7 and 11.5 mm in the young and adult capybaras, respectively. The findings of this study suggest that the age group should be taken into account when performing the anaesthetic block of the inferior alveolar and mental nerves in capybaras., (© 2022 Wiley-VCH GmbH.)

The present study aimed to evaluate the diet of the free-living crab-eating fox by identifying the stomach contents of the 17 crab-eating foxes (Cerdocyon thous) roadkilled in two conservation units, both located in the Amazon rainforest. The food items were quantified by frequency of occurrence (FO) and percentage of occurrence (PO). The stomach contents were analysed for dry matter (DM), crude protein (CP), crude fibre (CF), ether extract (EE), and mineral matter (MM). Nitrogen-free extractives (NFE), metabolisable energy (ME) values, as well as the energy need for maintenance were estimated. The composition of the diet for the crab-eating fox presented 29 food items from the different taxonomic groups, with a greater diversity of items of animal origin (n=22), although the highest frequency of occurrence was gramineae (Poaceae) (41.18%). Among the items of animal origin, 21% were mammals, 18% reptiles, 10% amphibians, 9% invertebrates and 3% birds. A high content of CF (62.76%) were determined. Nitrogen-free extractive and dry matter averages were 5.91% and 141.82 kcal/100g, respectively. The average maintenance energy was 447.01 kcal/day. These findings suggesting that the crab-eating foxes have a generalist diet with an omnivorous diet in the Amazon basin, feeding on gramineae, fruits, insects, snakes, amphibians, birds and small mammals and have the same feeding habit that present in other Brazilian biomes.

This study investigated the morphology and immunoexpression of aquaporins (AQPs) 1 and 9 in the rete testis, efferent ducts, epididymis, and vas deferens in the Azara's agouti ( Dasyprocta azarae ). For this purpose, ten adult sexually mature animals were used in histologic and immunohistochemical analyses. The Azara's agouti rete testis was labyrinthine and lined with simple cubic epithelium. Ciliated and non-ciliated cells were observed in the epithelium of the efferent ducts. The epididymal cellular population was composed of principal, basal, apical, clear, narrow, and halo cells. The epithelium lining of vas deferens was composed of the principal and basal cells. AQPs 1 and 9 were not expressed in the rete testis. Positive reaction to AQP1 was observed at the luminal border of non-ciliated cells of the efferent ducts, and in the peritubular stroma and blood vessels in the epididymis, and vas deferens. AQP9 was immunolocalized in the epithelial cells in the efferent ducts, epididymis and vas deferens. The morphology of Azara's agouti testis excurrent ducts is similar to that reported for other rodents such as Cuniculus paca . The immunolocalization results of the AQPs suggest that the expression of AQPs is species-specific due to differences in localization and expression when compared to studies in other mammals species. The knowledge about the expression of AQPs in Azara's agouti testis excurrent ducts is essential to support future reproductive studies on this animal, since previous studies show that AQPs may be biomarkers of male fertility and infertility., Competing Interests: Conflicts of interest: The authors have no conflict of interest to declare.

Baseline data for wall thickness in healthy toucans can be used to diagnose disease in sick individuals. This study aimed to evaluate the use of ultrasonography for the examination of the gastrointestinal tract of healthy toco toucans (Ramphastos toco). Ten non-anaesthetized healthy adult toco toucans were evaluated. Food was withheld for 3 h prior to the ultrasound examination. Longitudinal and transverse images of the gastrointestinal tract were obtained using ventromedian cranial and ventromedian caudal approaches to evaluate the morphology and stratification. The wall thickness of the sections was measured: proventriculus and ventriculus, duodenum, jejunum/ileum, and cloaca. Additionally, the thickness of the mucosal layer of the duodenum and jejunum/ileum was also measured. Subsequently, the ratios of the duodenal wall thickness to the duodenal mucosa layer and the total wall thickness of the jejunum/ileum to the jejunum/ileum layer mucosa were stablished. The wall thickness of the proventriculus was significantly higher than the wall thickness of ventriculus. The wall thickness of the duodenum was significantly higher than the wall thickness of jejunum/ileum. The mean ratios of the duodenal wall thickness to the duodenal mucosa layer and the wall thickness of the jejunum/ileum to the jejunum/ileum layer were 83.15% and 80.07%, respectively. In conclusion, it was possible to assess the stomach and intestines using ultrasound examination in healthy toco toucans, due to their medium body size and no interference by surrounding air sacs., (© 2021 Wiley-VCH GmbH.)

The aim of this study was to identify the anatomical structures in the head region of the giant anteater (Myrmecophaga tridactyla) using computed tomography. For this, three giant anteater corpses, adult and female, were used. The tomographic analysis was performed in sequential order in rostrocaudal direction. Subsequently, the heads of these animals were sectioned in cross sections of approximately 1.5 cm each. Tomographic images were compared with anatomical sections. The association between computed tomography and anatomical sections allowed the visualization of anatomical structures found in the nasal, oral, cranial, pharyngeal and ear cavities. An elongated oral cavity delimited by the elongated mandible was observed. The oral cavity was mainly occupied by a thin and elongated tongue formed mainly by the union of the sternoglossal muscles. The nasopharynx and oropharynx extended up to the neck at the level of the fifth cervical vertebra. The findings of this study suggest that the giant anteater has a head with structures morphologically adapted to its feeding habits, such as an elongated skull, tongue, styloid bones and mandible. In addition, based on the results of this study, it is possible to suggest that computed tomography is a pivotal tool for the veterinary routine of wild animals, since it allowed the identification of anatomical structures found in the head of the giant anteater., (© 2021 Wiley-VCH GmbH.)

The white-eared opossum present a higher roadkill number in Brazil, and the vertebral column is often affected when some type of trauma occurs. Thus, this study describes the osteology and radiology of the vertebral column in white-eared opossum to serve as a basis for support in the veterinary clinical care, since the casuistry of care of this marsupial has increased every year. Radiographs of the cervical (C), thoracic (T), lumbar (L), sacral (S) and caudal (Cd) segments of the vertebral column were taken in thirty-five white-eared opossums (Didelphis albiventris). Furthermore, ten opossums without evident vertebral acquired or congenital abnormalities at the radiographic study were selected for anatomical study. Osteology was correlated with the radiographic images. The use of radiographs allowed the identification of congenital and acquired vertebral changes, as well as the identification of anatomical structures, their distribution and morphology and the number of vertebrae. The vertebral formula varied in the white-eared opossum. In 27 of 35 white-eared opossums (77.2%) with normal vertebral morphology, three vertebral formulas were observed: C7/T13/L6/S2 (62.9%), C7/T13/L5/S2 (5.7%) and C7/T13/L7/S2 (8.6%). Most of the specimens presented 27 caudal vertebrae. The anticlinal vertebra was identified as T10 in 77.2% and T11 in 22.8% of opossums. Cervical block vertebra was observed in two animals and sacrocaudal block vertebra in one animal. The haemal arches could be seen from Cd3-Cd4 in 80% and Cd2-Cd3 in 20% of opossums. The white-eared opossum showed a slender vertebral column with a relatively short thoracic region, a relatively long lumbar region and a highly flexible lumbosacral transition, suggesting that this animal is a fast-running and agile opossum. Therefore, these findings may serve as a basis for further research and support the veterinary clinical care, since the casuistry of care for this marsupial has increased every year., (© 2020 Wiley-VCH GmbH.)

The aim of this study was to compare the arterial vascularization of the pelvic limb between southern caracara (Caracara plancus) and great egret (Ardea alba) by dissection and radiographic examinations. Five specimens of caracaras (three males and two females), and seven great egrets (five males and two females) were used. Barium sulphate and latex suspension were injected into the left ventricle of the birds. The radiographs were taken with the pelvic limbs in the ventrodorsal, dorsoplantar, mediolateral and lateromedial recumbency. Thereafter, the material was fixed in a 10% solution of formaldehyde and dissected. The pelvic limb received its arterial supply from two main vessels, the ischiatic and external iliac arteries. The ischiatic artery presented to be the principal artery of pelvic limb in the caracara and great egret. Several branches arised from the ischiatic and external iliac arteries were described. No gender differences were observed in both species. The caracara and great egret showed arteries similar to those reported for the ostrich and domestic fowl. According to the results of this study, it is suggested that the caracara has a pelvic limb with more arterial branches and larger arterial diameter than the great egret, which is probably related to the specific behaviour of these birds, since the caracara is a bird that exercise more their pelvic limbs to capture its prey when compared with the great egret., (© 2020 Wiley-VCH GmbH.)

Purpose: To evaluate the effects of alcohol exposure and diabetes on apoptotic process in the corpus cavernosum., Methods: Forty eight male Wistar rats were divided into four groups: control, diabetic, alcoholic and diabetic-alcoholic. Samples of the corpus cavernosum were prepared to study protein expression of apoptotic genes (Caspases-3 and 9) by immunohistochemistry and Real-Time PCR., Results: The immunoreactivity of Caspases-3 and -9 was diffuse and higher in the treated groups though there was no significant difference between the experimental groups, only when compared with the control group. An increase was observed in the gene expression of Caspases-9 in the diabetic and ethanol-diabetic groups when compared with control and ethanol groups., Conclusions: The association of these factors (ethanol and diabetes) probably can affect the apoptosis mechanism in lesions of the cavernous tissue in the rat penis. Both gene and protein expression of Caspase-9 in diabetic and ethanol-diabetic groups suggest the involvement of the apoptosis cascade from this study model.

Purpose: To evaluate the effect of chronic alcoholism on morphometry and apoptosis mechanism and correlate with miRNA-21 expression in the corpus cavernosum of rats., Methods: Twenty-four rats were divided into two experimental groups: Control (C) and Alcoholic group (A). After two weeks of an adaptive phase, rats from group A received only ethanol solution (20%) during 7 weeks. The morphometric and caspase-3 immunohistochemistry analysis were performed in the corpus cavernosum. The miRNA-21 expression was analyzed in blood and cavernous tissue., Results: Chronic ethanol consumption decreased cavernosal smooth muscle area of alcoholic rats. The protein expression of caspase 3 in the corpus cavernosum was higher in A compared to the C group. There was no difference in the expression of miRNA-21 in serum and cavernous tissue between the groups., Conclusion: Chronic ethanol consumption reduced smooth muscle area and increased caspase 3 in the corpus cavernosum of rats, without altered serum and cavernosal miR-21 gene expression.

The capybaras (Hydrochoerus hydrochaeris) are the largest rodent found throughout South America and are present in almost all the Brazilian territory, however, still lack basic descriptions about the species, such as about their cranial anatomy. This study was carried out to investigate the anatomical features in the capybara skull. Eight skulls and two heads, without sexual distinction, were used for the osteological, radiographic and tomographic identification of their structures. The skull of the capybara could be divided into a neurocranium and a viscerocranium. The capybara had a more robust and rectangular skull, elongated face caudally, thinned in the nasal region and slightly convex in the parietal region. The zygomatic arch was expanded and wide, the orbit had a circular shape, the infraorbital foramen was well developed, external acoustic meatus and tympanic bulla were relatively small, and the paracondylar process was large. These anatomical characteristics are compatible with the eating habit and semi-aquatic life of capybaras, which can be compared with characteristics reported for animals of similar habits. The radiographic image allowed to identify structures such as the frontal sinus, whereas 3D tomographic reconstruction was essential to have a spatial view of the skull of the capybara., (© 2020 Blackwell Verlag GmbH.)

The maternal nutritional status is essential to the health and well-being of the fetus. Maternal protein restriction during the perinatal stage causes sperm alterations in the offspring that are associated with epididymal dysfunctions. Vascular endothelial growth factor (VEGF) and its receptor, VEGFr-2, as well as aquaporins (AQPs) are important regulators of angiogenesis and the epididymal microenvironment and are associated with male fertility. We investigated the effects of maternal protein restriction on epididymal angiogenesis and AQP expression in the early stages of postnatal epididymal development. Pregnant rats were divided into two experimental groups that received either a normoprotein (17% protein) or low-protein diet (6% protein) during gestation and lactation. At postnatal day (PND)7 and PND14, male offspring were euthanized, the epididymides were subjected to morphometric and microvascular density analyses and to VEGF-A, VEGF-r2, AQP1 and AQP9 expression analyses. The maternal low-protein diet decreased AQP9 and VEGFr-2 expression, decreased epididymal microvascularity and altered the morphometric features of the epididymal epithelium; no changes in AQP1 expression were observed at the beginning of postnatal epididymal development. Maternal protein restriction alters microvascularization and affects molecules involved in the epidydimal microenvironment, resulting in morphometric alterations related to a delay in the beginning of epididymis postnatal development.

Opossums, the largest marsupials found in Brazil, are animals of great interest due to their commonality in large urban centres and their frequent use as laboratory animals. Thus, this study was designed to describe the vaginal complex in ten female opossums by gross anatomy and light microscopy. The vaginal complex comprises two lateral vaginae, a vaginal cul-de-sac and a urogenital sinus. No marked morphological contrast of the vaginal complex was observed in the proestrus and metestrus phases of the females studied. The epithelium lining of cul-de-sac was simple columnar and folded. The lateral vagina was lined by a stratified squamous epithelium that was keratinised in its cranial portion and nonkeratinised in the caudal region. The urogenital sinus was also lined by a stratified squamous epithelium. The morphology of vaginal complex of white-eared opossum is similar to those reported for other marsupials, showing similar histological features., (© 2018 Blackwell Verlag GmbH.)

This study aimed to describe the radiographic anatomy and osteology and to evaluate angular radiographic measurements-Norberg angle, inclination angle and anteversion angle-of the pelvic limbs in free-ranging capybaras. Twenty cadavers of free-ranging capybaras (Hydrochoerus hydrochaeris), including five adults and 15 subadults, were studied. Ventrodorsal, craniocaudal, dorsoplantar and mediolateral radiographic views of the pelvic limbs were obtained. The radiographic features were described together with bone samples. The hip bone (os coxae), shaped like an isosceles trapezoid, was elongated and narrow with the presence of an oblong obturator foramen, sagittal ilial wing and rectilinear ilial body. The femoral shaft was relatively straight, while the greater trochanter was projected above the femoral head. No sesamoid bones of the gastrocnemius and popliteus muscles were observed radiographically or for those animals used in gross macroscopy. The fibula was located lateral and parallel to the tibia. Eight tarsal bones, four metatarsal bones and three digits were identified. The mean radiographic measurements included Norberg angle of 125.9°; respective angles of femoral inclination by the Hauptman B and Tomlinson methods of 139.9 and 141°; anteversion angle of the femoral head and neck of 29.80°. The bones of the pelvic limbs in capybaras have several anatomical characters and radiological features that are shared with members of the caviomorph superfamily Cavioidea. The radiographic angles measured in this study help characterize the functional morphology of this species., (© 2018 Blackwell Verlag GmbH.)

Patella, the kneecap, is the best known and largest of the sesamoid bones and is present in the quadriceps femoris tendon. Typical patella appears in all extant mammals, with the exception of some marsupials and bats. No description about the white-eared opossum stifle was found in the available literature up to now. Thus, the knee joints of 16 Didelphis albiventris were examined by gross anatomy, histology, radiography and computed tomography images to determine the presence or absence of ossified patella in this animal. The most remarkable observation in white-eared opossum is the absence of a bony patella. The femoral trochlea is shallow, and the lateral gastrocnemius sesamoids are shown up in all opossums. The quadriceps femoris tendon is composed mainly of dense regular connective tissue with a classic fibrocartilage pad on the superficial surface of the tendon. The absence of a true patella seems to be typical for marsupials., (© 2017 Blackwell Verlag GmbH.)

Background: Although normal synovial fluid has been well characterized in domestic animals such as dogs, cats, horses, and cows, the available information on larger rodents is scarce., Objectives: The purpose of the study was to analyze the physical, chemical, and cytologic characteristics of the synovial fluid in stifle joints of Capybaras., Methods: Five free-ranging adult female Capybaras (Hydrochoerus hydrochaeris), weighing from 37 to 56 kg were used. Synovial fluid was obtained by aspiration of 10 stifle joints. Samples were analyzed for physical, chemical, and cytologic properties., Results: Spontaneous clotting was negative in 9 samples. Most synovial fluids had pH 8, and protein concentrations ranged from 1.6 to 3.6 g/dL. The mucin clot test was good in all 6 samples that were tested. Nucleated cell counts ranged from 140 to 508 cells/μL. Relative differential leukocyte counts demonstrated a predominance of mononuclear cells (97.6%), including 76.2% undifferentiated mononuclear cells, 18.1% macrophages, and 3.66% lymphocytes. Polymorphonuclear cells included 1.83% neutrophils and 0.2% eosinophils., Conclusion: The synovial stifle joint fluid of healthy free-ranging adult Capybaras is clear, colorless, viscous, and with chemical features and cytologic findings similar to those seen in domestic animals., (© 2017 American Society for Veterinary Clinical Pathology.)

This study aimed to evaluate the stifle joint of marsh deer using imaging studies and in comparison with gross anatomy. Ten hindlimbs from 5 marsh deer (Blastocerus dichotomus) were used. Radiography, computed tomography (CT) and magnetic resonance imaging (MRI) were performed in each stifle joint. Two hindlimbs were dissected to describe stifle gross anatomy. The other limbs were sectioned in sagittal, dorsal or transverse planes. In the craniocaudal radiographic view, the lateral femoral condyle was broader than the medial femoral condyle. The femoral trochlea was asymmetrical. Subsequent multiplanar reconstruction revealed in the cranial view that the external surface of the patella was roughened, the medial trochlea ridge was larger than the lateral one, and the extensor fossa at the lateral condyle was next to the lateral ridge. The popliteal fossa was better visualized via the lateral view. Sagittal MRI images identified lateral and medial menisci, caudolateral and craniomedial bundles of cranial cruciate ligament, caudal cruciate ligament, patellar ligament and common extensor tendon. In conclusion, the marsh deer stifle presents some anatomical characteristics of the ovine stifle joint., (© 2014 Blackwell Verlag GmbH.)

The features of paca epididymis, based on its appearance in light microscope, is described in this paper. The cellular population of the epithelial lining comprises principal cells, basal cells, apical cells, narrows cells, and hallo cells. The epididymis is divided in five distinct and continuous regions, Zone I, or initial segment, and zone II, are both localized into the head. Zone III comprises the distal head and all the body. Zones IV and V are restricted to the tail, in the proximal and distal cauda epididymis respectively. Each zone can be readily distinguished on the basis of morphological characteristics. The height of epididymal epithelium is greater in zone I. There is a progressive increase in the diameter of the tubular lumen through the different areas, with the maximum in the zone V. The presence of a high epithelium, and the virtual absence of sperm in zone I suggest fast transit of spermatozoa in this region. Zone V comprises the distal tail, has smaller epithelial lining, greater luminal diameter, shorter stereocilia than the other zones, and contains spermatozoa packed inside the lumen, that characterizes this zone as a place of sperm storage. The findings are compared with other reports in rodents and other domestic animals, to contribute to the understanding of epididymal morphophysiology.

The ultrastructure of the epididymal duct of the dog is described in this paper. The epididymis was divided into three morphofunctional segments: initial, middle and terminal. The cellular population of the lining epithelium is formed from principal, apical, basal and clear cells. The peritubular stroma and the tubular interstitium surrounding the epithelium are also described. The outcome is compared to the description made in other species of mammals.