Clavicle in Carnivorans: A Forgotten Bone.

The clavicle is a bone whose development is related to the versatility of the thoracic limbs in mammals. Studies with vestigial structures are scarce and controversial, especially in the order Carnivora. The objective of this study was to verify the presence and to investigate the shape and constitution of the clavicle in neotropical carnivores. In order to do this, 108 cadavers of 19 different species were collected dead on highways and were analyzed. The clavicles were submitted to dissections, longitudinal length measurements, radiographs, histological sections and, in some cases, diaphanization. Sixteen of the 19 species had clavicles in both sides, being significantly larger (P < 0.05) and distinctly more radiopaque in the felids than in the other families. There were no macro or microscopic evidence of clavicle in the specimens of Nasua nasua (n = 6), Conepatus semistriatus (n = 2), and Conepatus chinga (n = 1). The clavicle of the males of Lycalopex gymnocercus, Galictis cuja, and Leopardus geoffroyi was significantly larger (P < 0.05). The predominating contour of the clavicles was a thin stick with cranial convexity. The histological sections demonstrated compact bone consisting of trabecula and lamellae filled by bone marrow and different levels of occupation by chondroid matrix. It can be proposed the clavicles of the order Carnivora, although vestigial and rarely absent, have their presence, constitution and shape more associated with the phylogenetic proximity and evolutionary history of the species than to the variety of movements the thoracic limbs perform in free-living conditions. Anat Rec, 2019. © 2019 American Association for Anatomy Anat Rec, 303:1831-1841, 2020. © 2019 American Association for Anatomy.

Evaluation of monosodium iodoacetate dosage to induce knee osteoarthritis: Relation with oxidative stress and pain.

AIM: To determine the dose of monosodium iodoacetate (MIA) required to induce oxidative stress, as well as pain and edema; to confirm the induction of knee osteoarthritis (OA) symptoms in rats by the presence of reactive oxygen species (ROS) and reduction of antioxidant agents; and to verify the presence of histopathological injury in these affected joints. METHOD: Biological markers of oxidative stress, pain, knee edema, and cartilage degeneration provided by different doses of MIA (0.5; 1.0 or 1.5 mg) in rat knee joints were analyzed. The animal evaluations were conducted during 15 days for mechanical and cold hypersensitivity, spontaneous pain and edema. After that, blood serum, intra-articular lavage and structures of knee, spinal cord and brainstem were collected for biochemical analysis; moreover, the knees were removed for histological evaluation. RESULTS: This study demonstrates that the highest dose of MIA (1.5 mg) increased the oxidative stress markers and reduced the antioxidant reactions, both in the focus of the lesion and in distant sites. MIA also induced the inflammatory process, characterized by pain, edema, increase in neutrophil count and articular damage. CONCLUSION: This model provides a basis for the exploration of underlying mechanisms in OA and the identification of mechanisms that may guide therapy and the discovery of OA signals and symptoms.

Natural Sarcocystis gigantea infection in sheep from Southern Brazil / Infecção natural por Sarcocystis gigantea em ovinos no Rio Grande do Sul

ABSTRACT: Protozoal diseases caused by species of Sarcocystiscan cause serious damage in sheep flocks, inducing decreased growth conversion rates and partial or complete loss of carcasses at the slaughterhouse. This article describes an outbreak of Sarcocystis giganteainfection in sheep slaughtered in a farm in Rio Grande do Sul State, Brazil. Between July and September 2013, three sheep showed multiple nodules in the esophagus that were microscopically characterized as encapsulated cysts filled with elongated, basophilic, nucleated structures morphologically consistent with S. giganteabradyzoites. Diagnosis was made based on the epidemiological, macroscopic, and microscopic findings. This is the first report of this infection in sheep in Rio Grande do Sul and should be recognized by veterinarians, especially during meat inspection.

RESUMO: Doenças causadas por protozoários do gênero Sarcocystispodem causar sérios prejuízos em rebanhos de ovinos, por induzirem retardo no crescimento e condenação parcial ou total das carcaças em abatedouro. O presente trabalho descreve a infecção natural por Sarcocystis giganteaem ovinos abatidos em uma propriedade rural no Rio grande do Sul. Entre julho e setembro de 2013, três ovinos apresentaram múltiplos nódulos no esôfago, os quais, microscopicamente, corresponderam a cistos circundados por cápsula rugosa, repletos de estruturas alongadas, basofílicas e nucleadas, morfologicamente compatíveis com bradizoítos de S. gigantea.Os dados epidemiológicos unidos aos achados macroscópicos e microscópicos permitiram o diagnóstico conclusivo. Esse foi o primeiro relato dessa infecção no Rio Grande Sul e deve ser reconhecida por veterinários de campo e especialmente no momento da inspeção das carcaças no abatedouro.

Remoção da cartilagem articular associada ou não a implante homógeno ou enxerto autógeno de osso esponjoso em cães submetidos à artrodese atlantoaxial / Joint cartilage removal associated or not to homologous implant or autologous cancellous bone graft in dogs submitted to atlantoaxial arthrodesis

O objetivo deste estudo foi avaliar o grau de fusão articular e formação óssea na articulação atlantoaxial de cães submetidos à artrodese após a remoção da cartilagem articular associada ou não ao implante homógeno ou enxerto autógeno de osso esponjoso. Foram utilizados 12 cães, adultos, distribuídos aleatoriamente em três grupos iguais. Grupo I (GI): realizada apenas a remoção da cartilagem articular e imobilização articular com pinos e resina acrílica. Grupo II (GII): feita a remoção da cartilagem articular e imobilização da articulação, seguida da colocação e modelagem do implante ósseo esponjoso homógeno entre as superfícies articulares. Grupo III (GIII): foi realizado o mesmo procedimento do GII, mais o enxerto ósseo esponjoso autógeno no local determinado. Realizaram-se exames radiográficos em todos os animais aos 30, 60 e 90 dias de pós-operatório (PO). Aos 90 dias de PO foi feita a eutanásia para o emprego do teste de palpação manual, avaliação tomográfica e histopatológica. Para análise estatística da associação entre o grau de fusão articular, aplicou-se o Teste Qui-quadrado de independência. Os resultados dos testes foram avaliados pela significância exata e considerados significantes a 5% (P<0,05). Pelo teste de palpação manual e pelas imagens tomográficas, não houve diferença entre os grupos aos 90 dias de PO. A análise radiográfica da articulação atlantoaxial mostrou que o grau de fusão era semelhante entre os tratamentos entre os tempos de evolução. Com relação ao estudo histopatológico da articulação atlantoaxial dos cães, decorridos 90 dias de PO, foi verificado que a proliferação óssea no grupo I apresentou grau de intensidade proporcional, no grupo II, 75% leve e 25% acentuada e, no grupo III, 25% moderada e 75% acentuada. Não existe diferença quanto ao grau de fusão articular e formação óssea quando a técnica de artrodese atlantoaxial em cães for associada ao enxerto de osso esponjoso autógeno ou implante homógeno. A remoção da cartilagem articular isoladamente é uma alternativa eficiente e apresenta resultados semelhantes, quando associada ao enxerto autógeno ou implante homógeno.

The aim of this study was to evaluate the degree of joint fusion and bone formation in dogs undergoing atlantoaxial arthrodesis after removal of articular cartilage associated or not to implant homogenous or autogenous cancellous bone. Twelve dogs, weighing between 8 and 12kg were randomly divided into three groups. Group I (GI) performed only the removal of joint cartilage and joint immobilization with acrylic resin and pins. Group II (GII): after removel of joint cartilage and articular immobilization was performed modeling and placement of homogenous cancellous bone at the given location. The volume of homograft placed in the joint was measured using a precision balance and all animals received the same amount. Group III (GIII): this was the same procedure as GI, however, was used autogenous cancellous bone graft at the given location. Radiographic examinations were performed on all animals at 30, 60 and 90 days postoperatively. At 90 days of PO was carried out euthanasia of animals for testing of manual palpation and CT evaluation and histological. Samples were kept in solution in 10% buffered formaldehyde for fixation for a minimum of 72 hours and after, decalcified in formic acid and sodium citrate for subsequent processing and included in paraffin. Sections were stained with hematoxylin-eosin for light microscopy evaluation. Statistical analysis of the association between the degree of joint fusion assessed by manual palpation, the digitized radiographic images and CT scans and treatment groups, we applied the Chi-square test of independence. The test results were evaluated by the exact significance and considered statistically significant at 5% significance (P<0.05). By manual palpation test and by the CT images can be seen that there was no statistically significant difference between groups at 90 days postoperatively. Radiographic analysis of the atlantoaxial joint showed that the degree of fusion was similar among treatments, no statistical difference at 30, 60 and 90 days postoperatively. Regarding the histopathological study of atlantoaxial joint of dogs after 90 days postoperatively was found that bone formation in group I had 25% of each intensity (absent, mild, moderate, severe) in group II, 75% lighter and 25% sharp and in group III, 25% moderate and 75% severe. It can be concluded that the use of graft homogenous preserved in 98% glycerin in dogs undergoing atlantoaxial fusion method is a viable alternative for treatment of atlantoaxial instability. There is no difference in the degree of joint fusion and bone formation when the technique of atlantoaxial arthrodesis in dogs is associated with autogenous cancellous bone graft or implant homogenous. The removal of articular cartilage alone is an effective and shows similar results to the use of autograft or homogenous implant.

Molecular identification of bovine papillomaviruses associated with cutaneous warts in southern Brazil.

Bovine papillomaviruses (BPVs) are widespread pathogens mainly associated with benign, self-limiting, cutaneous lesions (warts). At least 8 viral types, defined by serology or nucleotide sequences of the L1 gene, have been identified to date. Different serotypes are associated with the specific type and morphology of the lesion and with particular geographical regions. This article describes the molecular identification of papillomaviruses from Brazilian cattle (n = 48) and horses (n = 1) through partial amplification and sequencing of the L1 gene. Bovine papillomavirus-1 (BPV-1) was identified in warts from 29 cattle (59%), BPV-6 from 9 cattle (18%), and BPV-2 in 8 lesions (16%). Warts of 2 cattle harbored L1 sequences of a new BPV type (BAA5), otherwise identified almost exclusively in healthy skin. The newly proposed BPV type "BR-UEL-4" was identified in a sarcoid tumor of a horse. Thus, the present report provides information on the main types of BPV involved in bovine papillomatosis in Brazil and reveals a new viral type associated with equine sarcoid, which to date has been attributed exclusively to BPV-1 and BPV-2.

Sarcoide equino associado ao papilomavírus bovino BR-UEL-4 / Equine sarcoid associated with bovine papillomavirus BR-UEL-4

Um equino, sem raça definida, macho com três anos de idade apresentou múltiplos nódulos na pele, em diversas regiões do corpo. As lesões localizavam-se predominantemente nos lábios, nas bochechas, na região submandibular e na região inguinal direita. Os tumores caracterizavam-se como sarcoides dos tipos misto, fibroblástico, verrucoso e oculto. Histologicamente apresentaram proliferação de fibroblastos dérmicos, muitas vezes ulcerado, com ou sem hiperplasia pseudoepiteliomatosa da epiderme e formação de pequenos grupos isolados de fibroblastos neoplásicos na derme superficial. Três amostras de tecido foram submetidas à extração de DNA e amplificação por PCR com oligonucleotídeos iniciadores genéricos direcionados para uma região interna do gene L1 dos papilomavírus. Os produtos resultantes da amplificação de duas amostras foram sequenciados e demonstraram identidade de 99 por cento com o papilomavírus bovino (BPV) BR-UEL-4. Essa é a primeira descrição da infecção de equinos, bem como de sua associação com sarcoide pelo BPV BR-UEL-4, um suposto novo tipo de BPV identificado recentemente no Brasil a partir de papilomas cutâneos em bovinos.

A 3-year-old, mixed breed, male horse showed multiple nodules in different areas of the skin. Lesions occurred predominantly on the lips, cheeks, and submandibular and right inguinal regions. The nodules were characterized as mixed, fibroblastic, verrucous and occult types of sarcoid. Histologically there was proliferation of dermal fibroblasts, with or without pseudoepitheliomatous hyperplasia of the epidermis (frequently ulcerated), and formation of small isolated groups of neoplastic fibroblasts in the superficial dermis. Three tissue samples were submitted to DNA extraction and PCR amplification with generic primers for the internal region of the papillomavirus L1 gene. The amplified products from two samples were sequenced and showed 99 percent identity with the bovine papillomavirus (BPV) BR-UEL-4. This is the first description of BPV BR-UEL-4 infecting a horse and causing sarcoid in this species. BPV BR-UEL-4 is a putative new BPV type recently identified in skin papillomas in a Brazilian cattle herd.

An outbreak of orthopoxvirus-associated disease in horses in southern Brazil.

An outbreak of severe cutaneous disease associated with an orthopoxvirus in horses in southern Brazil is described. Fourteen Crioulo mares and foals from a husbandry farm developed papules, and vesicles progressing to proliferative and exudative lesions on the muzzle, external nares, and external and internal lips. The vesicles eroded, and the proliferative lesions eventually bled and progressed to moist crusts and scars. The clinical signs lasted approximately 6-12 days, after which the animals progressively recovered. Direct electron microscopy of skin biopsies revealed brick-shaped, 250-300-nm virus particles with orthopoxvirus morphology. Histological examination of the lesions revealed vacuolar degeneration of the cells of the stratum spinosum and the presence of large intracytoplasmic, eosinophilic inclusion bodies. Polymerase chain reaction amplification of poxvirus A-type inclusion body gene confirmed the presence of orthopoxvirus DNA in horse tissues. Inoculation of tissue homogenates into the chorioallantoic membrane of chicken embryonated eggs and intraperitoneally in mice resulted in pock-like lesions with the microscopic appearance of poxvirus-induced histopathology. Taken together, these results demonstrate the association of an orthopoxvirus with the outbreak of cutaneous disease in horses. The origin of the agent causing the outbreak is uncertain because no similar condition has been reported in Brazil.

Poisoning of sheep by seeds of Crotalaria retusa: acquired resistance by continuous administration of low doses.

Seeds of Crotalaria retusa containing 6.84% (dry weight) of monocrotaline (MCT) were administered experimentally to sheep. Three sheep that received 136.8mg MCT/kg bw daily for 70 days had no clinical signs. Five out of six sheep ingesting single doses of 205.2 and 273.6mg MCT/kg bw died with acute (three sheep) or chronic intoxication (two sheep). Acute intoxicated sheep had periacinar liver necrosis and chronic intoxicated sheep liver fibrosis and megalocytosis. Another three sheep had no clinical signs after the ingestion of 20 daily doses of 136.8mg MCT/kg, followed by seven doses of 273.6mg MCT/kg, and one single dose of 342mg MCT/kg. These experiments demonstrated that sheep are susceptible to acute intoxication by MCT being intoxicated by a single oral dose of approximately 205.2mg/kg. In contrast, they develop strong resistance to MCT after the daily ingestion of non lethal doses (136.8mg/kg). It is suggested that chronic poisoning does not occur by the repeated ingestion of non acutely toxic doses, but probably by the ingestion of single toxic doses. It is also suggested that sheep do not become intoxicated with the ingestion of C. retusa in the vegetative non-seeding stage.

Aspectos imunoistoquímicos da hepatite infecciosa canina / Immunohistochemical aspects of canine infectious hepatitis

Tecidos de 27 cães que morreram de hepatite infecciosa canina (HIC) foram avaliados por imunoistoquímica (IHQ) para detecção de antígeno de adenovírus canino tipo 1 (CAV-1), por meio de um anticorpo monoclonal. Os tecidos examinados incluíram fígado, rim, baço, linfonodos, tonsilas, pulmão, intestino delgado, encéfalo e medula óssea. Para cada órgão foram atribuídos graus crescentes (de leve a acentuada) de intensidade de imunomarcação. O antígeno de CAV-1 estava presente na maioria dos órgãos examinados, principalmente em células endoteliais. Relacionando o tempo de evolução clínica da HIC com a intensidade da imunomarcação, o maior número de casos com evolução clínica hiperaguda ou aguda coincidiu com a maior intensidade de marcação do antígeno viral. A IHQ demonstrou ser um teste adequado para a detecção do antígeno de CAV-1 e pode ser usado para o estudo da patogênese da doença.

Tissues from 27 dogs died from infectious canine hepatitis (ICH) were evaluated by immunohistochemestry (IHC) for detection of canine adenovirus type 1 (CAV-1) antigen using a monoclonal antibody. Evaluated tissues included liver, kidney, spleen, lymph nodes, tonsils, lungs, small intestine, brain, and spinal cord. For each organ increasing degrees (from mild to marked) of intensity of immune staining were ascribed. CAV-1 was detected in most of the evaluated organs, mainly in the endothelial cells. Considering the clinical course of ICH and the intensity of IHC staining, cases with acute and peracute courses had more marked staining. IHC proved to be a reliable test for CAV-1 antigen detection and can be used for pathogenesis studies on ICH either in the spontaneous and experimental disease.