Skull of Capybara (Hydrochoerus hydrochaeris) - Morphometric Parameters

Background: The capybara (Hydrochoerus hydrochaeris) is the largest rodent in the world. They are territorial animals, and live in social groups, commonly occurring in anthropized area, what has attracted the attention of researchers in relation to this animal species, since it is the host of the Amblyomma cajennese tick that transmits spotted-fever to humans and are responsible for severe impact on livestock and public health. The skull is a part of the axial skeleton that enclosing the brain, sensory organs and digestive and respiratory structures. Moreover, the phenotypic appearance of the capybara head depends on the shape of the skull. Thus, the aim of this study was to describe the reference values of cranial measurements of capybaras. The knowledge of morphometric parameters of skull is pivotal for veterinary treatment of pathological conditions and taxonomic affiliation. Materials, Methods & Results: Eight capybaras (Hydrochoerus hydrochaeris) skulls were used in this study, irrespective of age and sex. The skulls belonging to the anatomical collection of the Laboratory of Wildlife Anatomy and Anatomical Museum, Department of Anatomy, Universidade Estadual Paulista Júlio de Mesquita Filho, UNESP, Botucatu, São Paulo. A total of 35 morphometric parameters were performed using a digital caliper and 6 cranial indices were calculated. All investigated features were expressed as mean ± standard deviation. Anatomically, capybara skull were elongated, rectangle-like and consisted of cranial and facial bones. The morphometric parameters were used to calculate the following craniometrics indices: skull index (57.86 ± 3.62), cranial index (50.49 ± 2.08), facial index (49.22 ± 3.82), basal index (33.98 ± 0.86), nasal index (26.73 ± 3.1), and the foramen magnum index (149.61 ± 1.07). Moreover, the facial part length (mean 137.90 mm) and cranium part length (mean 87.76 mm) also were calculated. The facial part length was a distance from the cribriform plate of the ethmoid bone to the rostral edge of the incisive bone and, the cranium part length was a distance from the external occipital protuberance to the cribriform plate of the ethmoid bone.  Discussion: This study established morphometric parameters in the capybara skull. The craniometric measurements showed in this study are compatible with reported in other studies in the capybara skull, although the most parameters measured in this study were not calculated in previous studies of the capybara skull. Moreover, none of the cranial indices calculated in this study were previously calculated. Based on some cranial measurements, the 8 capybaras used in this study could be classified into subadult (4) and adults (4). The foramen magnum showed a dorsal triangular notch in the capybara skull differently from described in the Cavia spp., and similar to reported to other rodent as Gambian rat and other mammals species such as maned wolf, four-toed hedgehog, and dromedaries. The rectangular shape of the capybara skull is different from that found in other caviids rodents such as Brazilian guinea pig. The capybara skull showed greater development of the facial part in relation to the cranial part, which allows to relate the skull shape with the skull shape presented by dolichocephalics dogs. This feature is commonly reported in large caviomorph rodents. Probably, this morphology is compatible with the ecology and phylogeny of the species. Keywords: capybaras, craniometry, cranium, veterinary anatomy, wildlife.

Unilateral Renal Agenesis in Chilean-Flamingo (Phoenicopterus chilensis)

Background: Phoenicopterus chilensis is a South American wild bird classified a species near threatened in the National List of Endangered Species of the International Union for Conservation of Nature. With the increase of the contact between human population and wild animals, this species’ habitat is becoming increasingly vulnerable, with a declining population. Due to the importance of its conservation, the knowledge of abnormalities that affect this species becomes essential. This report aims to describe the first diagnosed case of unilateral renal agenesis in chilean-flamingo.Case: A captive male chilean-flamingo (Phoenicopterus chilensis) was found dead in its enclosure and then was referred at necropsy. The cause of death was the presence of tracheal fungal granuloma, caused by Aspergillus sp. Macroscopically, during the examination of the cellomatic cavity, the absence of the right kidney was noted, also evidencing the absence of the caudal renal vein. Emerging from the caudal division of the kidney was noted a blind-end renal vessel (Figure 1). For the histopathological examination, the remaining kidney was fixed in 10% formalin, processed by paraffin embedding technique and stained with Hematoxylin and Eosin (HE). When analyzing the left kidney parenchyma, preserved histological architecture was noted, without any changes in the tissue structures of the organ. Thus, no hypertrophy by compensatory mechanisms of the remaining kidney was observed (Figure 2).Discussion: Unilateral renal agenesis is a very rare congenital defect in dogs, cats and also in birds. It occurs in the complete absence of one of the kidneys, a situation with which the animal can live satisfactorily if there is a normal kidney to assume the functions. In association, ipsilateral ureteral agenesis and compensatory hypertrophy of the remaining kidney may occur. At the time of necropsy, due to the remaining kidney has normal size and within topographic limits, dorsally in contact with the pelvis and sinsacrum, the absence of compensatory hypertrophy was suspected, which was confirmed by histopathological examination. Clinical signs of unilateral renal agenesis, when present, are related to renal failure. The signs develop when the remaining kidney fails to fully absorb the other's functions and fails to maintain the organism's homeostasis. In the case of this report, the specimen showed no clinical signs related to renal agenesis, probably because was no functional compensation for the single kidney. This condition was only noticed after flamingo necropsy, who death because tracheal fungal granuloma, caused by Aspergillus sp. Other reported ways of diagnosing this malformation in animals while alive were imaging and abdominal cavity surgery. The etiopathogenesis of unilateral renal agenesis in animals is uncertain, however, the hereditary cause is commonly described in rats and small animals. It cannot be concluded that the same happened with the animal of this study due to the fact of lack of data regarding the parents and history of animal. It is concluded that in unilateral renal agenesis, the compensatory hypertrophy of the remaining kidney and any clinical symptoms may not be present. Necroscopic and complementary exams are essential to obtain the diagnosis of unilateral renal agenesis. Knowing that the chilean-flamingo is considered as a species near threatened of extinction, it is important to know the abnormalities that affect this species, because this information may be essential for conservation programs

Avaliação do escore de condição corporal de machos adultos de cachorros-do-mato (Cerdocyon thous) sob cuidados humanos

Os cachorros-do-mato (Cerdocyon thous) são canídeos silvestres adaptados ao ambiente antropizado, atingindo o sucesso reprodutivo nesse novo habitat. Fator primordial para não constar na lista de ameaçados de extinção, como o lobo-guará (Chrysocyon brachyurus) e o cachorro-vinagre (Speothos venaticus). A complexidade do diagnóstico de doenças metabólicas em animais selvagens ainda é um desafio, tanto em vista a grande quantidade de estudos e a evolução da medicina de cães e gatos. Em cativeiro, os animais selvagens estão mais propícios a desenvolver obesidade, por isso, medidas de padrão da espécie fundamentados na conformação e biometria do indivíduo são necessários para se obter maior controle, não se baseando em dados subjetivos que podem diferir de acordo com o profissional O método mais fidedigno para avaliação da condição de escore corporal dos cachorros-do-mato (C. thous) desse estudo foi o método aplicado em gatos domésticos, no qual é necessário a  medida da caixa torácica e o comprimento do meio da patela para a ponta dorsal do calcâneo

Dermatophytosis Caused by Microsporum canis in a Free-Living Maned Wolf (Chrysocyon brachyurus).

Background: Chrysocyon brachyurus is a South American wild canid considered a species near threatened by the International Union for Conservation of Nature and is classified as vulnerable in the National List of Endangered Species. With the increase of the contact between domestic animals, human population and wild animals, there was a greater exposure of the maned wolf to pathogens. Due to the importance of its conservation, the knowledge of emerging infectious diseases that affect this species becomes essential. This report aims to describe the first diagnosed case of dermatophytosis caused by Microsporum canis in a maned wolf.Case: A free-living female maned wolf (Chrysocyon brachyurus), approximately 60 days old, was rescued with presence of alopecia, non-pruritic lesions, one of circular shape located in the nasal plane and the other with signs of scaling and crusts in the region of the left pina. The animal was active, in good general condition and without other significantchanges to clinical examination. Skin scraping was performed for mycological culture of both lesions. Fungal growth on Sabouraud’s agar identified Microsporum canis. Topical therapy with ketoconazole ointment and cleaning of lesions with 0.2% chlorhexidine was instituted. After 20 days of treatment, remission of clinical signs and repilation of affected areas were observed. New mycological cultures of both areas were carried out, which were negative for Microsporum canis.Discussion: Although Microsporum canis is described as causing dermatophytosis in several animal species, it has apparently not yet been reported in maned wolves. Microsporum canis is one of the most isolated zoophilic dermatophytes in domestic cats and is also cited in reports of symptomatic wild felids, such as tigers, in which it has been identified as either the only agent of infection or in association with Trichophyton mentagrophytes. The occurrence is also high in domestic dogs. In the wild canids, Microsporum gypseum has been described in the gray wolf, Trichophyton mentagrophytes in wild foxes, and Microsporum canis in red fox, among others. The finding of zoophilic and geophilic dermatophyte fungi in healthy, free-living and captive wild animals confirms their role as carriers, probable reservoirs and disseminators of these organisms in the environment, and the potential risk they represent as causes of zoonoses. Zoophilic dermatophytes are usually transmitted by contact between individuals and contaminated fomites. In the case of M. canis in the red fox the contact was an asymptomatic domestic cat. In the present case the transmission was not determined, since the animal was rescued from the wild. Regarding the age group, young animals are more susceptible to dermatophytes than adults, probably related to the greater immunity of adults due to previous contacts or even the immaturity of the immune system of the young. The dermatophytosis diagnosis is generally based on anamnesis, physical examination of the lesion, Wood’s lamp examination, microscopic skin scraping, fungal culture, or even histology and PCR tests. In the present case, the final diagnosis was based upon by fungal culture in Sabouraud agar, which allowed to identify the dermatophyte species and,thus, the possible source of infection. Dermatophyte infections can be treated with systemic or topical antifungal medications. Because it was a young animal, it was chosen in the present case only for topical use, which proved to be adequate, probably due to the action of the drug in the areas of alopecia skin and the improvement of the systemic condition of theanimal. Knowing that the maned wolf is considered as a vulnerable species, it is important to know the diseases that affect this species, in order to carry out, when necessary, disease monitoring programs, preventive and therapies, which is essential for its preservation.Keywords: wild animal, disease, skin, dermatophyte

Skull of Capybara (Hydrochoerus hydrochaeris) - Morphometric Parameters

Background: The capybara (Hydrochoerus hydrochaeris) is the largest rodent in the world. They are territorial animals, and live in social groups, commonly occurring in anthropized area, what has attracted the attention of researchers in relation to this animal species, since it is the host of the Amblyomma cajennese tick that transmits spotted-fever to humans and are responsible for severe impact on livestock and public health. The skull is a part of the axial skeleton that enclosing the brain, sensory organs and digestive and respiratory structures. Moreover, the phenotypic appearance of the capybara head depends on the shape of the skull. Thus, the aim of this study was to describe the reference values of cranial measurements of capybaras. The knowledge of morphometric parameters of skull is pivotal for veterinary treatment of pathological conditions and taxonomic affiliation. Materials, Methods & Results: Eight capybaras (Hydrochoerus hydrochaeris) skulls were used in this study, irrespective of age and sex. The skulls belonging to the anatomical collection of the Laboratory of Wildlife Anatomy and Anatomical Museum, Department of Anatomy, Universidade Estadual Paulista Júlio de Mesquita Filho, UNESP, Botucatu, São Paulo. A total of 35 morphometric parameters were performed using a digital caliper and 6 cranial indices were calculated. All investigated features were expressed as mean ± standard deviation. Anatomically, capybara skull were elongated, rectangle-like and consisted of cranial and facial bones. The morphometric parameters were used to calculate the following craniometrics indices: skull index (57.86 ± 3.62), cranial index (50.49 ± 2.08), facial index (49.22 ± 3.82), basal index (33.98 ± 0.86), nasal index (26.73 ± 3.1), and the foramen magnum index (149.61 ± 1.07). Moreover, the facial part length (mean 137.90 mm) and cranium part length (mean 87.76 mm) also were calculated. The facial part length was a distance from the cribriform plate of the ethmoid bone to the rostral edge of the incisive bone and, the cranium part length was a distance from the external occipital protuberance to the cribriform plate of the ethmoid bone.  Discussion: This study established morphometric parameters in the capybara skull. The craniometric measurements showed in this study are compatible with reported in other studies in the capybara skull, although the most parameters measured in this study were not calculated in previous studies of the capybara skull. Moreover, none of the cranial indices calculated in this study were previously calculated. Based on some cranial measurements, the 8 capybaras used in this study could be classified into subadult (4) and adults (4). The foramen magnum showed a dorsal triangular notch in the capybara skull differently from described in the Cavia spp., and similar to reported to other rodent as Gambian rat and other mammals species such as maned wolf, four-toed hedgehog, and dromedaries. The rectangular shape of the capybara skull is different from that found in other caviids rodents such as Brazilian guinea pig. The capybara skull showed greater development of the facial part in relation to the cranial part, which allows to relate the skull shape with the skull shape presented by dolichocephalics dogs. This feature is commonly reported in large caviomorph rodents. Probably, this morphology is compatible with the ecology and phylogeny of the species. Keywords: capybaras, craniometry, cranium, veterinary anatomy, wildlife.