Behavioral, productive, and reproductive aspects of the water buffalo in Mexico

Water buffalo (Bubalus bubalis) production in Mexico has generated particular interest in understanding the bases of the development of this species. As a result, alliances have emerged between scientific, governmental, industrial, and productive sectors and other organisms involved with this species nationally and internationally. We must recognize that thanks to specific anatomical characteristics, water buffaloes present a low incidence of complications during calving, though they are not exempt from obstetric and perinatological problems that can end in morbidity and mortality for mother and/or offspring, with losses for both branches of dual-purpose production systems: calves-milk and meat, and draft animals. This article analyzes scientific advances related to water buffalo production in Mexico, including productivity, thermoregulation, behavior, and physiology, and key subthemes like obstetric and perinatological handling, imprinting, milking, and dual-purpose production systems. It highlights features inherent to milk production and the neurophysiological and metabolic processes involved in obtaining meat and milk. Finally, it presents a brief overview of current legislation and summarizes key areas of opportunity.(AU)

Radiographic pelvimetry in the Tamandua tetradactyla / Pelvimetria radiográfica em Tamandua tetradactyla

The pelvis, formed by the ilium, ischium and pubis, forms the coxal, which is the largest of the flat bones of the skeleton, with an important role in the physiology of birth. Vastly studied in domestic animals, there is still much to be investigated regarding the anatomical classification in wild animals, mainly aiming to improve the understanding of the reproductive management of the species. Tamandua tetradactyla is one of these species in which morphological studies are still scarce, especially when it comes to reproductive aspects. In this context, we carried out the pelvimetry of T. tetradactyla using radiographic images to anatomically and obstetrically classify the pelvis of this species, classifying it as dolicopelvic, with evidence of homoscedasticity of the samples. Verification of the existence of a relationship between the variables studied by the statistical method of Pearson coefficients showed positive correlations of high intensity for the diameters studied (P < 0.01). Thus, we believed that our findings may support future reproductive studies in this species.

A pelve, constituída pelo ílio, ísquio e púbis, forma o coxal, sendo este o maior dos ossos planos constituintes do esqueleto, com importante papel na fisiologia do parto. Vastamente estudada em animais domésticos, ainda existe muito à se investigar quanto a classificação anatômica nos animais selvagens, visando principalmente melhorar a compreensão do manejo reprodutivo das espécies. Tamandua tetradactyla é uma dessas espécies em que estudos morfológicos ainda são escassos, principalmente quando se trata de aspectos reprodutivos. Neste contexto realizamos a pelvimetria do T. tetradactyla por meio de imagens radiográficas para classificar anato-obstetricamente a pelve desta espécie classificando-a como dolicopélvica, sendo evidenciada homoscedasticidade das amostras. A verificação da existência de relação entre as variáveis estudadas pelo método estatístico dos coeficientes de Pearson mostrou correlação positivas de alta intensidade para os diâmetros estudados (P< 0,01). Assim, acreditamos que nossos achados poderão subsidiar futuros estudos reprodutivos nesta espécie.

Morphological study of the digestive tract of the cardinal tetra, Paracheirodon axelrodi (Characiformes: Characidae)

The cardinal tetra Paracheirodon axelrodi is a species of the family Characidae of great interest as an ornamental fish. Many aspects of the biology of this species are still unknown. The present work presents a complete description of the different components of the digestive tract of P. axelrodi, analyzing its global anatomical arrangement, the adjacent glands (liver and pancreas) and the previously ignored pyloric caeca, using histological and histochemical techniques with light microscopy and scanning electron microscopy. Three levels of analysis were performed: macroscopic anatomy, histology of the gastrointestinal tract and scanning electron microscopy of mucosal surfaces. The intestinal coefficient (Ci) of P. axelrodi calculated here (0.94) is within the expected range for a carnivorous species. The anatomy of the alimentary and the resulting Ci is consistent with carnivorous diet in line with dietary studies in the wild in this species. The digestive tract, including adjacent glands (liver and pancreas), presented a relatively conserved general pattern within that described for other species of the family Characidae, especially at the histological level.(AU)

El tetra cardenal Paracheirodon axelrodi es una especie de la familia Characidae de gran interés como pez ornamental. Muchos aspectos de la biología de esta especie son aún desconocidos. En este trabajo se presenta una descripción completa de los diferentes componentes del tracto digestivo de P. axelrodi, analizando su disposición anatómica global, las glándulas adyacentes (hígado y páncreas) y la presencia de ciegos pilóricos, mediante técnicas histológicas e histoquímicas con microscopía óptica y electrónica de barrido. Se realizaron tres niveles de análisis: anatomía macroscópica, histología del tracto gastrointestinal y microscopía electrónica de barrido de las superficies mucosas. El coeficiente intestinal (Ci) de P. axelrodi calculado aquí (0,94) está dentro del rango esperado para una especie carnívora. Los estudios anatómicos del tracto alimentario y el Ci son consistentes con una dieta carnívora en línea con los estudios de la dieta en ejemplares silvestres en esta especie. El tracto digestivo, incluyendo las glándulas adyacentes (hígado y páncreas), presentó un patrón general relativamente conservado dentro de lo descrito para otras especies de la familia Characidae, especialmente a nivel histológico.(AU)

Carcinoma de células escamosas (cce) em cão na região prepucial: relato de caso / Squamous cell carcinoma (scc) in dog in the preputial region: case report / Carcinoma de células escamosas (cce) en perro de la región prepucial: reporte de un caso

A expectativa de vida dos animais de companhia vem aumentando devido as mudanças comportamentais e de cuidados dos tutores. Em analogia, com as idades cada vez mais avançadas, é comum o desenvolvimento de doenças associadas, sendo o tumor o mais comum entre elas. Todavia, as neoplasias mais comuns na clínica de pequenos animais estão associadas ao sistema tegumentar. O carcinoma de células escamosas (CCE), ou carcinoma espinocelular, é uma neoplasia de epitélio, maligno, de crescimento lento e de baixo potencial metastático. Sua etiologia ainda não é precisamente conhecida e a causa exógena mais comum e descrita pela literatura é a exposição à luz ultravioleta, gerando consequentes lesões nas estruturas genéticas e imunogênicas na pele. Além disso, essas lesões apresentam-se de forma mais comum em animais de pelagem clara, com grande exposição solar e em área anatômicas hipopigmentadas. O prognóstico varia de acordo com a localização e o estágio clínico, sendo favorável o diagnóstico realizado precocemente, e o tratamento consiste na avaliação clínica seguida do protocolo adequado O presente relato de caso tem como objetivo principal reunir e discutir informações associadas sobre o carcinoma de células escamosas em caninos e felinos, abordando aspectos clínicos e patológicos, a fim de facilitar o raciocínio sobre o CCE, desde sua abordagem inicial, até seu diagnóstico final e estadiamento.(AU)

The life expectancy of companion animals has been increasing due to behavioral and care changes of the guardians. In analogy, with the increasingly advanced ages, the development of associated diseases is common, the tumor being the most common among them. However, the most common neoplasms in the small animal clinic are associated with the integumentary system. Squamous cell carcinoma (SCC), or squamous cell carcinoma, is a malignant, slow-growing, low-potential metastatic epithelial neoplasm. Its etiology is not yet precisely known and the most common exogenous cause described by the literature is exposure to ultraviolet light, generating consequent lesions on the genetic and immunogenic structures in the skin. In addition, these lesions are more common in light-haired animals, with high exposure to the sun, and in hypopigmented anatomical areas. The prognosis varies according to the location and clinical stage, being favorable to the early diagnosis, and the treatment consists in the clinical evaluation followed by the appropriate protocol. The present case report has as its main objective to gather and discuss associated information about squamous cell carcinoma in canines and cats, addressing clinical and pathological aspects, in order to facilitate the reasoning about the CCE, from its initial approach, to its final diagnosis and staging.(AU)

La esperanza de vida de los animales de compañía ha ido en aumento debido a los cambios de comportamiento y cuidado de los guardianes. Por analogía, con las edades cada vez más avanzadas, el desarrollo de enfermedades asociadas es común, siendo el tumor el más común entre ellos. Sin embargo, las neoplasias más comunes en la clínica de animales pequeños se asocian con el sistema tegumentario. El carcinoma epidermoide (CCE), o carcinoma epidermoide, es una neoplasia epitelial metastásica maligna de crecimiento lento y bajo potencial. Su etiología aún no se conoce con precisión y la causa exógena más común descrita por la literatura es la exposición a la luz ultravioleta, generando lesiones consecuentes en las estructuras genéticas e inmunogénicas de la piel. Además, estas lesiones son más comunes en animales de pelo claro, con alta exposición al sol, y en áreas anatómicas hipopigmentadas. El pronóstico varía según la localización y el estadio clínico, siendo favorable al diagnóstico precoz, y el tratamiento consiste en la evaluación clínica seguida del protocolo adecuado. El presente reporte de caso tiene como objetivo principal reunir y discutir información asociada sobre el carcinoma epidermoide en caninos y gatos, abordando aspectos clínicos y patológicos, con el fin de facilitar el razonamiento sobre el CCE, desde su abordaje inicial, hasta su diagnóstico final y estadificación.(AU)

Mastectomia a campo em ruminantes - aspectos cirúrgicos e clínico-patológicos / Field mastectomy in ruminants - surgical and clinicopathological aspects

Background: We report the case of 3 cows, 1 ewe, and 1 doe, with chronic mastitis and which underwent a mastectomy. All animals had a history of mastitis, edema with purulent secretion in the udder region, areas of abscess formation, fibrosis, hypogalactia, and agalactia. The animals had already been treated with systemic antibiotic therapy and anti-inflammatory drugs without response. The objective of this work is to describe the surgical and clinicopathological aspects of performing a radical mastectomy in the field in 3 cows and 1 ewe, and a partial mastectomy in a doe, with both procedures performed successfully and considered efficient to maintain the survival of the affected animals, in addition to being economically viable. Cases: In all animals reported in the study, a general and a specific clinical examination were performed, where on palpation of the udder were observed an increase in the region of the mammary apparatus, fluid fluctuation, areas of fibrosis with increased stiffness, and loss of udder functionality. In the case of the doe, there was a functional teat, which was preserved during the surgical procedure. Radical mastectomy was performed in 3 cows and 1 ewe, and the doe underwent a partial mastectomy, with preservation of the functional teat. All animals have fasted for food and water for 48 h. In cows, the anesthetic protocol consisted of 2% xylazine hydrochloride [0.15 mg/kg, intramuscularly (IM)], followed by an epidural block in the lumbosacral region with 2% lidocaine hydrochloride [10 mL]. The midazolam hydrochloride [0.1 mg/kg, intravenously (IV)] and 2% xylazine hydrochloride [0.05 mg/kg, IM] were administered to the ewe and the doe, also associated with lumbosacral epidural anesthesia with 2% lidocaine hydrochloride [5 mL]. The animals were positioned in the right lateral decubitus position and the entire abdominal and udder region were shaved and sanitized for the surgical procedures of radical mastectomy and partial mastectomy, with the use of degerming and topical povidone-iodine. The postoperative period consisted of penicillin-based antibiotic therapy associated with streptomycin [24,000 IU/kg, IM, 10 consecutive days] and flunixin meglumine [2 mg/kg, IM, 3 consecutive days] in cows; enrofloxacin [2.5 mg/kg, IM, 7 consecutive days] and flunixin meglumine [0.5 mg/kg, IM, 5 consecutive days] in the ewe; oxytetracycline [10 mg/kg, IM, 5 applications on alternate days] and flunixin meglumine [0.5 mg/kg, IM, 3 consecutive days] in the doe. In all animals, the cleaning of the surgical wound was performed daily with 10% topical Povidone-iodine and Permethrin ointment, for 14 days, when the stitches were removed. Discussion: The choice of the surgical procedure resulted in improvement of the clinical conditions and increased survival of all animals, and in the case of the doe, partial mastectomy contributed to the preservation of the functional teat, preserving its productive capacity. All anesthetic protocols used and the anatomical positioning of the animals were satisfactory for performing the procedures. Although they are techniques described in the literature with great blood loss, especially in cows, blood transfusion was not required in any of the animals. The stitches were removed 14 days after the surgical procedures, and the surgical wound was completely healed.

Anatomical description of the ventral and dorsal cervical rootlets in rats: A microsurgical study

Purpose: To describe the anatomical aspects of the cervical rootlets and to quantify the number of rootlets that compose C1 to T1. Methods: Twenty male rats were used in this study. The dorsal rootlets from C1 to T1 were analyzed. To study the ventral rootlets, the posterior root avulsion was performed using a microhook, allowing exposure of the ventral roots through manipulation of the denticulate ligament and arachnoid mater. The parameters analyzed were the number of ventral and dorsal rootlets by side and level. Results: The formation of the respective spinal nerve was observed in the spinal roots the union of the ventral and dorsal roots. In four animals the C1 spinal root had no dorsal and/or ventral contribution. There is no normal pattern of numerical normality of the dorsal and ventral rootlets. The average number of fascicles per root was 4.08, with a slight superiority on the left side. There was a slight superiority of the dorsal rootlets compared to the ventral rootlets. Conclusions: This investigation was the first to study cervical rootlets in rats. In 20% of the sample studied, the dorsal root of C1 was absent mainly on the left side. There is a nonlinear numerical increase from C1 to T1 in the rootlets. There is a numerical predominance of cervical fascicles on the left side, confronting several studies related to the functional predominance of right laterality, requiring new studies that correlate these variables.

Morphological study of the pineal gland of Alouatta belzebul / Estudo morfológico da glândula pineal de Alouatta belzebul

The pineal is a neuroendocrine gland responsible for the synthesis and release of melatonin. It is present in the brain of vertebrates, but its morphology and location vary considerably among species. For the species Alouatta belzebul, although some anatomical aspects of the nervous system have been described, there is no information on the morphology and histological composition of this gland. Thus, the present study aimed to describe the morphological, morphometric, and histological aspects of the pineal of Alouatta belzebul. Seven adult specimens were dissected from which the location of the gland in relation to the surrounding brain structures was described, and its length and width were measured. Histological slides were then prepared and stained using hematoxylin-eosin and PAS techniques. It was observed that the pineal of Alouatta belzebul is located superior and cranial to the cerebellum, superior to the superior colliculi and below the splenium of the corpus callosum and was classified as sub-callosal. It had an average length of 2.6mm and an average width of 1.14mm. Histologically the gland is composed of irregular strands of pinealocytes and gliocytes. The pinealocytes showed pigments similar to melanin.

A pineal é uma glândula neuroendócrina responsável pela síntese e liberação de melatonina. Está presente no encéfalo dos vertebrados, mas sua morfologia e localização variam consideravelmente entre as espécies. Para a espécie Alouatta belzebul, apesar de terem sido descritos alguns aspectos anatômicos do sistema nervoso, não há informações sobre a morfologia e composição histológica desta glândula. Assim, o presente estudo teve como objetivo descrever os aspectos morfológicos, morfométricos e histológicos da pineal de Alouatta belzebul. Foram dissecados sete encéfalos de espécimes adultos dos quais se descreveu a localização da glândula em relação às estruturas encefálicas circunvizinhas e foram realizadas medidas de comprimento e largura da mesma. Em seguida foram preparadas lâminas histológicas e coradas pelas técnicas de hematoxilina-eosina e PAS. Observou-se que a pineal de Alouatta belzebul localiza-se superior e cranialmente ao cerebelo, superior aos colículos superiores e abaixo do esplênio do corpo caloso e foi classificada como subcalosa. Apresentou comprimento médio de 2,6mm e largura média de 1,14mm. Histologicamente a glândula é composta por cordões irregulares de pinealócitos e gliócitos. Os pinealócitos apresentaram pigmentos semelhante à melanina.

Melanomas em cães no Sertão do Nordeste do Brasil - epidemiologia, fatores de risco e achados clinicopatológicos / Melanoma in dogs in the backlands of Northeastern Brazil - epidemiology, risk factors and clinicopathological findings

Background: Melanoma is a malignant neoplasm that arises from melanocytes and malanoblasts. It is also more frequently reported in dogs than in other species. They may arise from melanocytes in the skin, on the surfaces of the mucous membranes, and eyes. The aim of this study was to describe the epidemiological aspects, risk factors and clinicopathological findings of melanoma in dogs in the backlands, northeastern Brazil. Materials, Methods & Results: A retrospective study was carried out in all biopsy samples and necropsy examinations of dogs, from January 2003 to December 2021, at the Animal Pathology Laboratory of the Federal University of Campina Grande, Patos, Paraiba, northeastern Brazil. Epidemiological data, clinical signs, and gross lesions were reviewed from the diagnostic laboratory reports. Samples of the skin, lymph nodes, central nervous system and organs of the thoracic and abdominal cavities were fixed in 10% buffered formalin, processed routinely for histopathology, embedded in paraffin wax, cut into 4 µm sections, and stained with hematoxylin and eosin (HE). Histological sections were also submitted to immunohistochemistry with the primary antibody anti-Melan A. Of the 4717 records found, 1158 (24.5%) were diagnosed with neoplasms, of which 48 (4.14%) cases were of melanoma. Of this total, 28 (58.3%) dogs were elderly, 19 (39.6%) were adults, and 1 (2.1%) was young. Mixed breed animals were the most affected (42.6%), followed by the pinscher breed (19.1%). According to the anatomical region, the most affected site was the skin (38/53=71.7%), followed by the oral cavity (12/53=22.65%) and the eyes (3/53=5.7%). Grossly, the skin lesions were characterized by exophytic and usually blackened, sometimes irregular and firm, nodules. At cut, they had a smooth, compact and blackened surface. Lesions in the oral cavity were characterized by blackened, irregular and infiltrating nodules or masses. The ocular lesions were always unilateral and were characterized by an enlarged and diffusely blackened eyeball, with areas of ulceration and subversion of tissue architecture. In 5 animals there was more than one anatomical site affected, totaling 53 lesions. In 9 (17%) cases, metastases were identified, 8 in regional lymph nodes and 1 in the lung. Histopathology showed a densely non-encapsulated, poorly delimited, expansive and infiltrative neoplasm, composed of neoplastic cells arranged in islands or nests and supported by fibrovascular stroma, containing a variable amount of brownish pigment (melanin). Immunohistochemistry showed strong immunostaining of the neoplastic cells in brown by the anti-Melan A antibody. Discussion: The diagnosis of melanoma was established based on epidemiological, clinical, anatomopathological, and immunohistochemical findings. Gender is not a predisposing factor, and although there was no statistically significant relationship, males were more affected. Senescence is a conditioning risk factor. Elderly animals were more affected (P < 0.0001) than adult ones, with OR = 4.38; and young ones (P = 0.0051), with OR = 12.65. Some breeds, especially those with marked skin pigmentation, were more affected, however the most affected ones in this survey were pinscher and poodle. Cutaneous melanoma accounted for almost 72% of cases, contesting recent studies where oral cavity melanoma was more frequent. Therefore, it is believed that the climatic conditions of the backlands sub-region, in northeastern Brazil, associated with the individual characteristics of the dogs, are involved in the development of these neoplasms, since the climate is predominantly dry, with high temperatures throughout the year, with maximums that can reach 40ºC, favoring the exposure to high incidence of ultraviolet radiation.

Oropharyngeal morphological aspects of Arapaima gigas (Schinz, 1822) / Aspectos morfológicos orofaríngicos de Arapaima gigas (Schinz, 1822)

The study of the functional anatomy of the digestive system of fish, in particular the oropharyngeal cavity, is of great importance because it allows inferences about the feeding habit, mechanisms of capture, selection, and processing of food carried out by different species. Thus, the aim of this stu-dy was to describe the anatomical adaptations of the oropharyngeal cavity of the pirarucu (Arapai-ma gigas Schinz, 1822) using scanning electron microscopy (SEM) techniques. The oropharyngeal cavity of six specimens of pirarucu was collected in juvenile phase, from Aquaculture Research Cen-ter at the Universidade Federal de Rondônia (UNIR), created for commercial purposes. The anato-mical pieces were fixed in 10% buffered formalin and processed for SEM analysis. Anatomically, the oropharyngeal cavity of the pirarucu is composed of five pairs of branchial arches, apical portion of the tongue, floor of the tongue, lower pharyngeal area, and upper pharyngeal plate. In SEM, we observed that the mucosa of the apex of the tongue and the upper pharyngeal roof have a smooth texture and are covered by squamous cells with numerous small openings scattered over the surfa-ce. The portions of the floor of the tongue and the lower pharyngeal area, on the other hand, have adaptations in the form of a projectile and numerous sensory papillae, giving a rough texture to the region. Thus, the oropharyngeal cavity of pirarucu is adapted for the capture, apprehension, and swallowing of its prey, with signs of carnivory.(AU)

O estudo da anatomia funcional do aparelho digestivo dos peixes, em particular da cavidade orofa-ríngea, é de grande importância, pois permite inferências sobre o hábito alimentar, mecanismos de captura, seleção e processamento de alimentos realizados por diferentes espécies. Assim, o objetivo do estudo foi descrever as adaptações anatômicas da cavidade orofaríngea do pirarucu (Arapaima gigas Schinz, 1822) por meio de técnicas de microscopia de varredura eletrônica (MEV). A cavidade orofaríngea de seis espécimes de pirarucu foi coletada na fase juvenil, no Centro de Pesquisa em Aquicultura da Universidade Federal de Rondônia (UNIR), criado para fins comerciais. As peças anatômicas foram fixadas em formalina tamponada a 10% e processadas para análise em MEV. Ana-tomicamente, a cavidade orofaríngea do pirarucu é composta por cinco pares de arcos branquiais, porção apical da língua, assoalho da língua, região faríngea inferior e placa faríngea superior. Na MEV, a pesquisa observou que a mucosa do ápice da língua e o teto faríngeo superior possuem textura lisa e são recobertos por células escamosas com numerosas pequenas aberturas espalha-das pela superfície. As porções do assoalho da língua e da região faríngea inferior, por outro lado, apresentam adaptações em forma de projétil e numerosas papilas sensoriais, conferindo textura áspera à região. Assim, a cavidade orofaríngea do pirarucu é adaptada para a captura, a apreensão e a deglutição de sua presa, com sinais de carnivoria.(AU)

Anatomical description of the extratemporal facial nerve under high-definition system: a microsurgical study in rats

Purpose: To describe the microsurgical anatomical aspects of the extratemporal facial nerve of Wistar rats under a high-definition video system. Methods: Ten male Wistar rats (12­15 weeks old), without veterinary diseases, weighing 220­280 g, were used in this study. All animals in this study were submitted to the same protocol and by the same surgeon. A 10-mm incision was made below the bony prominence of the right or left ear, and extended towards the angle of the mandible. The dissection was performed and the main branches of the facial nerve were dissected. Results: The main trunk of the facial nerve has a length of 0.88 ± 0.10 mm and a length of 3.81 ± 1.03 mm, measured from its emergence from the stylomastoid foramen to its bifurcation. Seven branches originating from the facial nerve were identified: posterior auricular, posterior cervical, cervical, mandibular, buccal, temporal, and zygomatic. Conclusions: The anatomy of the facial nerve is comparable to that of humans, with some variations. The most observed anatomical division was the distribution in posterior auricular, posterior cervical, cervical, mandibular, buccal, temporal, and zygomatic branches. There is no statistical difference between the thickness and distance of the structures compared to the contralateral side.

Segunda opinião diagnóstica na anatomia patológica / Second opinion on pathological anatomy

A anatomia patológica, veterinária e humana, no contexto mundial, adota, com cada vez mais frequência, a prática de segunda opinião diagnóstica, como método de verificação e confirmação de pareceres técnicos, objetivando uma maior acurácia e precisão dos diagnósticos fornecidos. Este trabalho tem por objetivo discorrer sobre a importância da segunda opinião diagnóstica na anatomia patológica e seus aspectos éticos. A segunda opinião reflete uma medida de precisão diagnóstica e, apesar de alguns sítios anatômicos ou áreas de subespecialidade apresentarem maiores frequências de grandes discordâncias diagnósticas, quase todas as áreas no âmbito da anatomia patológica podem ser clinicamente afetadas pela segunda opinião. Dadas as variações entre as instituições, recomenda-se a revisão de segunda opinião de todos os locais anatômicos em todas as instituições, públicas e privadas, para maximizar a descoberta de divergências clinicamente relevantes.

Human and veterinary medicine pathological Anatomy in the world context, increasingly adopts the practice of second diagnostic opinion, as a method of verification and confirmation of technical opinions, aiming at greater accuracy and precision of the diagnoses provided. This work aims to discuss the importance of the second diagnostic opinion in pathological anatomy and its ethical aspects. The second opinion reflects a measure of diagnostic accuracy, and although some anatomical sites or areas of subspecialty have higher frequencies of major diagnostic disagreements, almost all areas within the pathological anatomy can be clinically affected by the second opinion. Given the variations between institutions, a second opinion review of all anatomic sites in all institutions, public and private, is recommended to maximize the discovery of clinically relevant discrepancies.

Comparative anatomical studies on the cranial nerves of the fully formed embryos of the Nile tilapia Oreochromis niloticus (Ostiechthyes-Cichlidae). I. Nervus glossopharyngeus / Estudos anatômicos comparativos dos nervos cranianos de embriões totalmente formados da tilápia do Nilo Oreochromis niloticus (Ostiechthyes Cichlidae). I. Nervus glossopharyngeus

The organization of the roots, ganglia and the peripheral distribution of the cranial nerves of the fully formed embryos of Oreochromis niloticus are examined in the transverse serial sections. These nerves carry fibers, which were also analyzed. The results of this study demonstrated that the glossopharyngeal nerve originates by means of only one root, which leaves the cranium through the glossopharyngeal foramen. This nerve gives fibers (visceromotor) to the first internal and external levator arcus branchialis muscles. There is a single epibranchial (petrosal) ganglion located extracranially. Nervus glossopharyngeus has three rami; pharyngeus, pretramticus and posttrematicus. The ramus pharyngeus carries only viscerosensory fibers; general for the pharyngeal epithelium and special ones for the pseudobranch. General viscerosensory fibers are also carried by rami pretrematicus and posttrematicus for the pharyngeal epithelial lining. The special sensory fibers are carried by the ramus pretrematicus for the taste buds and by ramus posttrematicus for the gill filaments. The ramus pretrematicus also carries visceromotor fibers for the first adductor arcus branchialis and to the first obliquus ventralis muscles.

A organização das raízes, gânglios e a distribuição periférica dos nervos cranianos dos embriões totalmente formados de Oreochromis niloticus são examinados nas seções transversais seriais. Esses nervos carregam fibras, que também foram analisadas. Os resultados deste estudo demonstraram que o nervo glossofaríngeo se origina por meio de apenas uma raiz, que sai do crânio pelo forame glossofaríngeo. Este nervo fornece fibras (visceromotoras) para os primeiros músculos levantadores do arco branquial interno e externo. Existe um único gânglio epibranquial (petroso) localizado extracranialmente. Nervus glossopharyngeus tem três ramos; faríngeo, pretramticus e póstrematicus. O ramo faríngeo contém apenas fibras viscerossensoriais — gerais para o epitélio faríngeo e especiais para o pseudobrânquio. Fibras viscerossensoriais gerais também são transportadas por ramos pretrematicus e posttrematicus para o revestimento epitelial da faringe. As fibras sensoriais especiais são transportadas pelo ramus pretrematicus para as papilas gustativas e pelo ramus posttrematicus para os filamentos branquiais. O ramo pretrematicus também carrega fibras visceromotoras para o primeiro adutor arcus branchialis e para o primeiro músculo oblíquo ventral.

Comparative anatomical studies on the cranial nerves of the fully formed embryos of the Nile tilapia Oreochromis niloticus (Ostiechthyes-Cichlidae). I. Nervus glossopharyngeus / Estudos anatômicos comparativos dos nervos cranianos de embriões totalmente formados da tilápia do Nilo Oreochromis niloticus (Ostiechthyes Cichlidae). I. Nervus glossopharyngeus

The organization of the roots, ganglia and the peripheral distribution of the cranial nerves of the fully formed embryos of Oreochromis niloticus are examined in the transverse serial sections. These nerves carry fibers, which were also analyzed. The results of this study demonstrated that the glossopharyngeal nerve originates by means of only one root, which leaves the cranium through the glossopharyngeal foramen. This nerve gives fibers (visceromotor) to the first internal and external levator arcus branchialis muscles. There is a single epibranchial (petrosal) ganglion located extracranially. Nervus glossopharyngeus has three rami; pharyngeus, pretramticus and posttrematicus. The ramus pharyngeus carries only viscerosensory fibers; general for the pharyngeal epithelium and special ones for the pseudobranch. General viscerosensory fibers are also carried by rami pretrematicus and posttrematicus for the pharyngeal epithelial lining. The special sensory fibers are carried by the ramus pretrematicus for the taste buds and by ramus posttrematicus for the gill filaments. The ramus pretrematicus also carries visceromotor fibers for the first adductor arcus branchialis and to the first obliquus ventralis muscles.(AU)

A organização das raízes, gânglios e a distribuição periférica dos nervos cranianos dos embriões totalmente formados de Oreochromis niloticus são examinados nas seções transversais seriais. Esses nervos carregam fibras, que também foram analisadas. Os resultados deste estudo demonstraram que o nervo glossofaríngeo se origina por meio de apenas uma raiz, que sai do crânio pelo forame glossofaríngeo. Este nervo fornece fibras (visceromotoras) para os primeiros músculos levantadores do arco branquial interno e externo. Existe um único gânglio epibranquial (petroso) localizado extracranialmente. Nervus glossopharyngeus tem três ramos; faríngeo, pretramticus e póstrematicus. O ramo faríngeo contém apenas fibras viscerossensoriais — gerais para o epitélio faríngeo e especiais para o pseudobrânquio. Fibras viscerossensoriais gerais também são transportadas por ramos pretrematicus e posttrematicus para o revestimento epitelial da faringe. As fibras sensoriais especiais são transportadas pelo ramus pretrematicus para as papilas gustativas e pelo ramus posttrematicus para os filamentos branquiais. O ramo pretrematicus também carrega fibras visceromotoras para o primeiro adutor arcus branchialis e para o primeiro músculo oblíquo ventral.(AU)

Penile fractures in young bulls raised in feedlots in Southern Brazil

Background: Penile fracture is a pathology of young cattle that perform precocious and disordered breeding. The incompatibility of height between males and females and sodomy between males cause a great pressure on the sigmoid flexure and retractor muscle of the penis, which are the main causes and sites of organ injury. This study aimed to describe the epidemiological and pathological aspects of penile fractures observed in young bulls raised in pre-export feedlots (PEFs) in southern Brazil. Cases: In 2 PEFs located in the municipalities of Pelotas (property 1) and Capão do Leão (property 2), 3 male cattle [1 from property 1 and 2 from property 2] presented subcutaneous edema in the foreskin and perineum, associated with dysuria. The evolution of the clinical picture was approximately 20 days in all cases, with evolution to death. The bovine necropsied on property 1 had an increased volume and inguinal edema, involving the penis and scrotal sac. Necrosis of the subcutaneous tissue and local musculature was also observed. The testicles were surrounded by the necrotic tissue, and the right testis was swollen, with flaccid parenchyma adhering to the tunica albuginea. In the necropsy of 1 bull from property 2, an increase in the inguinal volume was observed, with an extensive area of necrosis and edema extending from the prepuce to the caudal musculature of the scrotal sac. There were also marked varicosis in the sigmoid flexure and necrosis of the adjacent region, without the involvement of the corpus cavernosum. During the necropsy of the 2 young bulls, fragments of organs from the abdominal, thoracic, and brain cavities were collected and fixed in 10% buffered formalin. From the bull of the property 2, an anatomical piece consisting of the penis, prepuce, and testicles was also collected and fixed in 10% buffered formalin. After 48 h, the tissue samples were cleaved, embedded in paraffin, cut into 3-µm-thick sections, and stained using hematoxylin and eosin (HE). A histological evaluation of the penile lesions in both cattle revealed intense hemorrhage, congestion, and necrosis of the muscles and tissues adjacent to the corpus cavernosum. In addition to areas of dystrophic calcification, neutrophil and macrophage infiltration was also observed. In the bull from the property 1, an intense edema and proliferation of fibrous tissue surrounding the urethra were noted. There were also marked tubular degeneration and intense infiltration of neutrophils, lymphocytes, and macrophages in the inner portion of the tunica albuginea. Discussion: In the present cases, the diagnosis was based on epidemiological data associated with clinical signs and pathology. The macroscopic lesions observed were probably due to the involvement of blood vessels adjacent to the penis, which suffered trauma during sodomy mating among cattle. These lesions have been described in other reports of this pathology and in diseases, such as acropostitis-phimosis, fibropapilloma of the glans, preputial abscess, and urolithiasis, and the differential diagnosis of these diseases must be carried out, as they have different etiologies. In the bulls of the present study, no lesions were observed in the corpus cavernosum, and this condition was attributed to the presence of varicosis and accumulation of urine in the prepuce, due to the difficulty in exposing the penis. Histologically, there were intense hemorrhage, congestion, and necrosis of the muscles and tissues adjacent to the corpus cavernosum, with the infiltration of neutrophils and macrophages, and areas of dystrophic calcification. The presence of necrotic lesions in tissues adjacent to the penis may be related to hypoxia, vascular lesions, or the action of chemical elements present in the urine. In both cases, vascular lesions were present, which were attributed to the main triggering factor for the disease.

Cardiovascular system of agouti (Dasyprocta prymnolopha)

Background: The species Dasyprocta prymnolopha is a wild rodent with a geographic distribution that extends from Mexico to South America, including Brazil. Agouti has been the subject of morphophysiological research, but data on the cardiovascular system remains limited. Therefore, the objective was to describe the macroscopic and microscopic morphology, including the study of the cardiac and coronary system syntopy of the species D. prymnolopha. Materials, Methods & Results: Twelve Dasyprocta primnolopha adults were used, 6 males and 6 females. Topographic analysis of the heart was evaluated in situ, with subsequent measurement, anatomovascular description and macroscopic study of cardiac and coronary vascularization. A microscopic investigation and identification of structural cardiac aspects were also carried out in adult agoutis, the biological samples of the heart were submitted to histological techniques and stained with Hematoxylin and Eosin and Masson's Trichrome. The heart is located between the end of the 2nd and the beginning of the 5th intercostal space, with the apex reaching the 6th space. It presents the presence of 2 ligaments: phrenopericardium and sternopericardium. The right atrioventricular valve is composed of 2 cusps, the parietal and the septal, with variations within the same species for 3 cusps. Projections that interconnect the papillary muscles with each other were observed. In the left ventricle there are variations in the number of papillary muscles (range 2 to 4). In the region of the aortic valve, 5 ostia were observed in the left aortic sinus in all animals. The coronary circulation has a predominantly left distribution. Histologically, the heart consists of 3 main layers: endocardium, myocardium, and epicardium. The cusp valves of the atrioventricular openings are composed of endocardial folds that contain a central plate of dense connective tissue, and inserted in this cardiac musculature was observed the cardiac skeleton, with its fibrous ring consisting of collagen and elastic fibers that surrounds the atrioventricular opening. Discussion: Cardiac assessment in wild animals is challenging, as in-depth knowledge of the morphology of the cardiovascular system is required for the use of diagnostic tools. In this first anatomical study of the heart, this organ presents syntopy with those of other rodents, but the topography may vary in individuals of the same species, which may be related to the accentuated vertebral curve. The phrenopericardial and sternopericardial ligaments were observed in this research, although there are no reports in other species of Dasyprocta sp. The arrangement of the arteries has, as a particularity, the larger left atrium in relation to the heart/atrium size ratio when compared to other domestic species, covering the left coronary sinus until it reaches the left atrial surface. In the agouti, it was observed that the vascularization is left, with the left coronary artery giving rise to both the paraconal and subsinuous interventricular branch, a fact found in animals such as ruminants, dogs. In the histological observations of the present study, the heart was similar to that of other mammals. Our data reveal morphological characteristics similar to those of other mammals, but with very expressive characteristics that differ even within the species. It is important to generate new information to elucidate cardiac and coronary diagnostic analyses, which can be extended to different species.

Aneurisma aórtico torácico com trombose associada em Bugio-preto (Alouatta caraya) / Thoracic aortic aneurysm with associated thrombosis in black-and-gold howler monkey (Alouatta caraya)

O aneurisma é uma dilatação anormal e permanente das artérias, resultante do enfraquecimento da parede do vaso adelgaçamento da camada média e enfraquecimento da camada elástica. Em animais, a maioria dos casos de aneurisma tem origem idiopática e são detectados acidentalmente durante a necropsia. O objetivo deste trabalho é relatar um caso de aneurisma aórtico com trombose associada em Bugio-preto(Alouatta caraya), bem como seus aspectos patológicos. O animal era adulto, macho, pertencente ao Centro Nacional de Primatas (CENP), na cidade de Ananindeua-PA, foi encaminhado para exame necroscópico para investigação da causa mortis. No histórico do animal, não constava qualquer enfermidade. O animal apresentava bom escore de condição corporal com preservação da topografia anatômica dos órgãos. Entretanto, observou-se presença de aumento de volume localizado em aorta torácica, a 1,4 cm da base do coração. Na abertura aórtica foi observado dilatações de tamanhos variados e, no interior da maior dilatação, notou-se uma estrutura de coloração vermelho escuro, aderida, de aspecto seco e superfície áspera, medindo 1,5 cm. Aneurismas aórticos em primatas não humanos não são comuns, porém já foram reportados na literatura. O diagnóstico precoce utilizando exames complementares é importante, porém, ainda há recursos não empregados na rotina veterinária tornando ainda mais difícil o diagnóstico e prevenção. Por isso, na medicina veterinária, os aneurismas são detectados acidentalmente durante a necropsia. Com base nos achados anatomopatológicos, concluiu-se que o animal veio a óbito por trombose associada a aneurisma aórtico.

An aneurysm is an abnormal and permanent dilation of the arteries, resulting from the weakening of the vessel wall.thinning of the middle layer and weakening of the elastic layer. In animals, most cases of aneurysm are idiopathic. This paper aimed to report a case of aortic aneurysm with associated thrombosis in a black-and-gold howler monkey(Alouatta caraya), as well as its pathological aspects. The animal was an adult, male, belonging to the National Primate Center (CENP), in the city of Ananindeua-PA, that was referred for necroscopic examination to investigate the causa mortis. In the animal's history, there was no disease. The animal had a good body condition score with preservation of the anatomical topography of the organs. However, there was an increase in volume located in the thoracic aorta, 1.4 cm from the base of the heart. In the aortic opening, dilations of different sizes were observed, and inside the largest dilatation, a structure of dark red color, adhered, with a dry appearance and rough surface, measuring 1.5 cm was noted in addition to dilations of different sizes. Inside the largest cavitation, a dark red structure was observed, adhered, with a dry appearance and rough surface, measuring 1.5 cm. Aortic aneurysms in non-human primates are incommon, but have been reported in the literature. Early diagnosis using complementary exams is important, however, there are still resources not used in the veterinary routine, making diagnosis and prevention even more difficult. Therefore, in veterinary medicine, aneurysms are accidentally detected during necropsy. Based on the anatomopathological findings, it was concluded that the animal died due to thrombosis associated with an aortic aneurysm.

Hermafroditismo verdadeiro na espécie suína / True hermaphroditism in the swine specie

Os hermafroditas verdadeiros são animais com intersexualidade, nos quais as gônadas masculinas e femininas se desenvolvem simultaneamente no mesmo indivíduo. Este trabalho relata um caso de hermafrodita na espécie suína após descarte de uma fêmea por diagnóstico de anestro. Tratava-se de uma fêmea com 222 dias de idade e 150 kg a qual havia sido selecionada para reprodução e permanecia em anestro. O indivíduo foi descartado e enviado para o abate em frigorífico sob inspeção federal. Após o abate foi observado no sistema genital aspectos anatômicos sugestivos de hermafroditismo. O sistema genital foi coletado, inspecionado macroscopicamente e conservado em formol a 10% para avaliação microscópica. Durante a análise macroscópica foi verificada a presença de vulva e vagina, contendo um pênis rudimentar. O útero, a cérvix, os cornos uterinos e oviduto estavam presentes e com ausência de anormalidade. Havia um ovário esquerdo com aspectos morfológicos de ciclicidade e folículos contendo oócitos de alta qualidade. À direita, entretanto, foi constatada a presença de um testículo, epidídimo e plexo pampiniforme. A avaliação histopatológica comprovou os achados macroscópicos, demonstrando um ovário contendo folículos, corpos lúteos e cistos foliculares; plexo pampiniforme; testículo e epidídimo com aspecto histológico normal, porém, com ausência de células espermatogênicas. Assim, com base nos achados macro e microscópicos descritos nesse relato de caso, o indivíduo foi considerado como hermafrodita verdadeiro.(AU)

True hermaphrodites are intersexual animals, in which both male and female gonads develop simultaneously in the same individual. This paper reports a case of a true hermaphrodite in the swine species after its culling for anestrus. The specimen was a female of 222 days of age and 150 kg of body weight, that was selected for reproduction and was permanently in anestrus. This individual was culled and sent to an abattoir under federal inspection. After slaughtering, it was observed in the reproductive tract anatomical aspects that suggested hermaphroditism. The reproductive tract was collected, evaluated macroscopically, and preserved in formaldehyde at 10 % to be evaluated by light microscopy. During the macroscopic analysis, the presence of a vulva and a vagina with a rudimentary penis was detected. The uterus, the cervix, uterine horns, and the oviduct were present and abnormalities were not detected. The left ovary exhibited morphological signs of cyclicity and contained follicles with high quality oocytes. On the right side, however, it was observed a testicle, epididymis, and a pampiniform plexus. The histopathological assessment corroborated the macroscopic findings, which demonstrated that the ovary had follicles, corpus luteum, and follicular cysts, and pampiniform plexus, testicle and epididymis were histologically normal, though with the absence of spermatogenic cells. Thus, based on the macro and microscopic findings described herein, the individual was considered a true hermaphrodite.(AU)

Artéria subclávia direita aberrante em cão - aspectos clínicos e de imagem / Aberrant right subclavian artery in a dog - clinical and imaging aspects

Background: Aberrant right subclavian artery is only rarely observed in veterinary medicine. Some animals may present postprandial regurgitation and progressive weight loss, which is considered an incidental finding unrelated to clinical alterations. Advanced imaging techniques such as thoracic CT scan, magnetic resonance imaging (MRI) and contrast angiography are used for the accurate detection of lesions, anatomical changes and specific information about vascular rings. This paper describes the clinical changes, imaging exams and therapeutic approach in a female dog with megaesophagus induced by an aberrant right subclavian artery. Case: A 2-month-old female bull terrier, weighing 1.6 kg, with a history of regurgitation immediately or a few minutes after a meal, diarrhea, polyphagia, progressive emaciation and apathy for 45 days, was treated at a University Veterinary Hospital. The dog's physical examination revealed 7% dehydration and body condition score 1 (scale 1 to 5), but no cardiac or pulmonary alterations upon auscultation. The hematological analysis and renal and hepatic serum enzymes were within the normal range for the species. In view of the presumptive clinical diagnosis of vascular anomaly, suggested by the contrast X-ray examination, a chest tomography was performed, which revealed altered aortic arch shape and contours, and a posterior aneurysm in the area of abnormal connection of the right subclavian artery. The patient was released with a prescription for conservative dietary management for megaesophagus. Within two weeks, the patient returned with a report of a good response to the prescribed therapy, absence of vomiting and diarrhea, and an increase in body weight. Surgical correction was recommended, but has not been performed so far, but conservative treatment for megaesophagus was continued. No further episodes of regurgitation were identified during the nine-month follow-up period. Discussion: In the case reported here, the right subclavian artery is considered anatomically atypical because it arises directly from the aortic arch. This vascular anomaly passes on to the right pectoral limb, dorsal to the esophagus, contracting it in its dorsal aspect. It tends to affect purebred dogs, occurring more frequently in Irish setters, German shepherds and Labrador retrievers, although it has been described in other breeds such as the bull terrier documented here and mixed breed dogs. Vascular ring anomalies may not cause clinical changes in animals and represent only incidental findings, or they may lead to gastrointestinal changes resulting from esophageal stricture, contributing to megaesophagus and clinical signs of esophageal obstruction, especially in recently weaned puppies. Such alterations were observed in this case, with the dog presenting regurgitation, immediately or a few minutes after a meal, megaesophagus, diarrhea and progressive weight loss. A CT scan was performed to confirm the type and location of the vascular anomaly and diagnostic accuracy, as recommended in the literature. Dietary therapy is one of the approaches adopted for patients presenting with regurgitation resulting from megaesophagus secondary to vascular anomalies. The dog in this report responded well to the medical therapy; nevertheless, the treatment of choice to correct the esophageal obstruction caused by this anomaly is surgical sectioning of the aberrant vessel by right intercostal thoracotomy, given that the degree of esophageal dilation and dysfunction tends to increase over time. However, at this time, the animal's owner decided to suspend the recommended surgical procedure.

Birds of prey pellet analysis: morphometry and consumption interval of captive Accipitridae species / Análise de pelotas de aves de rapina: morfometria e intervalo de consumoem espécies da família Accipitridae em cativeiro

Pellet production is a typical characteristic of the digestive physiology of birds of prey. Alimentary pellets consist of non-digested parts of prey, such as fur, feathers, bones, and parts of insects, that are regurgitated. Obtained dietary samples, such as regurgitated pellets, can noninvasively contribute to the knowledge of the anatomical alimentary channel and the digestive efficiency of birds of prey. The aim of this study was to evaluate the pellet morphometry and meal-to-pellet interval (MPI) of the Accipitridae family subjected to two experimental diets. Heterospizias meridionalis, Rupornis magnirostris, and Geranoaetus albicaudatus were subjected to (1) mice and (2) quail pre-treating diets. Both diets were individually weighed and provided by removing excess feathers, skin, and some viscera. After consumption, the MPI was noted and, immediately after collection, the pellets were carefully weighed on a precision balance and morphometric measurements were taken using a caliper. Pellet weight, length, width, height, and volume were higher when raptors consumed mice. Differences in morphometric characteristics were found between species. Heterospizias meridionalis presented the highest values for the morphometric parameters evaluated. Consumption of mice increased the frequency of regurgitation and the number and weight of pellets egested, indicating that by providing this type of food, we can underestimate the consumption by birds if we do not consider nutritional losses by the pellets when calculating diets. Pellet assessment and MPI are important tools for monitoring the health and nutritional aspects of birds of prey.

A produção de pelotas é uma característica típica da fisiologia digestiva de aves de rapina. As pelotas alimentares consistem em partes não digestíveis de presas como peles, penas, ossos e partes de insetos que são expelidos. A obtenção de amostras como as pelotas podem colaborar de forma não invasiva com o conhecimento da anatomia do canal alimentar e eficiência digestiva de rapinantes. O objetivo desse estudo foi avaliar a morfometria e o intervalo entre consumo e egestão de pelotas (ICP) em indivíduos da família Accipitridae. Heterospizias meridionalis, Rupornis magnirostris e Geranoaetus albicaudatus foram submetidos a dietas pré processadas com(1) camundongos e (2) codornas. Ambas as dietas foram individualmente pesadas e fornecidas após a remoção do excesso de penas, pele e algumas vísceras. Após o consumo, o ICP foi calculado e imediatamente após a coleta as pelotas foram pesadas e avaliadas quanto a medidas morfométricas com a ajuda de um paquímetro. O peso, comprimento, largura, altura e volume das pelotas foram maiores quando as aves consumiram ratos. Diferenças morfométricas foram encontradas entre as espécies. Heterospizias meridionalis apresentaram os valores mais altos para os parâmetros morfométricos avaliados. O consumo de camundongos aumentou a frequência de egestão, o número e o peso das pelotas, indicando que, ao fornecer este tipo de alimento, podemos subestimar o consumo pelas aves se não considerarmos as perdas nutricionais pelas pelotas ao calcular as dietas. A avaliação de pelotas e ICP são ferramentas importantes para monitorar os aspectos sanitários e nutricionais em rapinantes.

Anatomical aspects of the forearm muscles of Myrmecophaga tridactyla / Aspectos anatômicos dos músculos do antebraço de Myrmecophaga tridactyla

The giant anteater is one of the species classified as vulnerable to extinction. Burning and being run over are among important causes in the decrease of individuals of this species and a better knowledge of the anatomy of these animals can contribute to the treatment of injured animals and their restoration to the environment. Thus, the objective of this work was to describe aspects of the anatomy of the muscles of the forearm of M. tridactyla. For this purpose, six adult specimens were used, three females and three males. The corpses were fixed with a 10% formaldehyde solution and preserved in vats containing the same solution. The thoracic limbs were dissected by routine dissection techniques. The forearm muscles of M. tridactyla were: brachioradialis; radial carpal extensor; common finger extensor; lateral finger extensor, ulnar carpal extensor; finger extensor I and II; long abductor of finger I; supinator, radial carpal flexor; ulnar flexor of the carpus, superficial flexor of the fingers, deep flexor of the fingers, pronator teres and square pronator, which were innervated by the radial, ulnar and median nerves. These muscles give a large volume to the forearm, are robust and have highly developed tendons, especially those involved with the flexion of the carpus, digits and elbow, actions that are fundamental to your defense habits and search for food.(AU)

O tamanduá-bandeira é uma das espécies classificadas em condição vulnerável à extinção. Queimadas e atropela-mentos estão entre causas importantes na diminuição de indivíduos desta espécie e um melhor conhecimento da anatomia des-tes animais pode contribuir para o tratamento de animais feridos e seu reestabelecimento ao meio ambiente. Assim, oobjetivo deste estudo foi descrever os aspectos da anatomia do antebraço do M. tridactyla. Para tanto, foram utilizados seis exemplares adultos, sendo três fêmeas e três machos. Os cadáveres foram fixados com solução aquosa de aldeído fórmico 10% e preser-vados em cubas contendo a mesma solução. Os membros torácicos foram dissecados pelas técnicas rotineiras de dissecação para evidenciação dos músculos, vasos e nervos da região. Os músculos do antebraço do M. tridactyla foram: braquiorradial; extensor radial do carpo; extensor comum dos dedos; extensor lateral dos dedos, extensor ulnar do carpo; extensor dos dedos I e II; abdutor longo do dedo I; supinador, flexor radial do carpo; flexor ulnar do carpo, flexor superficial dos dedos, flexor profundo dos dedos, pronador redondo e pronador quadrado. Estes músculos foram inervados pelos nervos ulnar e mediano. Juntos estes músculos conferem um grande volume ao antebraço, e suas características apontam para uma poderosa capaci-dade de exercer a flexão do carpo e dos dígitos, e ainda contribuir com os músculos do braço para a flexão do cotovelo, ações estas fundamentais aos seus hábitos de defesa e busca por alimento.(AU)