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This study describes the pathologic findings of 24 humpback whales (Megaptera novaeangliae) found stranded along the Brazilian coast from 2004 to 2016. Eighteen (75%) animals evaluated were found stranded alive. From these, 13 died naturally on shore and five were euthanized. Six died at sea and were washed ashore. Of the 24, 19 (79.2%) were calves, four (16.7%) were juveniles, and one (4.2%) was an adult. The most probable cause of stranding and/or death (CSD) was determined in 23/24 (95.8%) individuals. In calves, CSD included neonatal respiratory distress (13/19; 68.4%), infectious disease (septicemia, omphaloarteritis and urachocystitis; 3/19; 15.8%), trauma of unknown origin (2/19; 10.5%), and vehicular trauma (vessel strike; 1/19; 5.3%). In juveniles and adult individuals, CSD was: emaciation (2/5; 40%), sunlight-thermal burn shock (1/5; 20%); and discospondylitis (1/5; 20%). In one juvenile, the CSD was undetermined (1/5; 20%). This study integrates novel findings and published case reports to delineate the pathology of a South-western Atlantic population of humpback whales. This foundation will aid in the assessment of the population health and establish a baseline for development of conservation policies.

A retrospective study of 24 cases of papillomas in dogs was performed from January 2001 to March 2011. Additionally, immunohistochemistry (IHC) was used to characterize and evaluate the samples. We found that disease was observed more in mixed breed dogs, ages ranging from 6 months to 10 years (mean 3.1 years), and there was no gender predilection. The main lesion sites were the skin (75%), lips (16.7%), and eyelids (8.3%). Upon histological evaluation, we observed papillary exophytic proliferation of squamous epithelium and papillary endophytic proliferation (inverted) in 87.5% and 12.5% of cases, respectively. The tumors were characterized by spinous layer hyperplasia (87.5%) with koilocytes (70.8%) and intranuclear pale basophilic inclusions bodies (8.3%), prominent granular layer with large amounts of keratohyalin granules (95.8%), and hyperkeratosis in the stratum corneum (100%). Positive immunostaining for Papillomavirus was found in 83.3% of cases, which were distributed between the granular layer and the stratum corneum. These findings indicate the following: that papillomas in dogs are caused by Papillomavirus, the viral cytopathic effect induces epithelial lesions, viral particles are found inside the cell nuclei, and inclusions bodies are rare.

In this retrospective study was determined the frequency of canine skin peripheral nerve sheath tumors (PNST) in cases diagnosed by the Setor de Patologia Veterinária of the Universidade Federal do Rio Grande do Sul (SPV-UFRGS), Brazil, between the years 2000 and 2012. The canine profiles, as well as histological, immunohistochemical and prognostic aspects of the tumors were based on 70 samples, comprising 40 females, 29 males and one unspecified sample. Between 2000 and 2012, 2,984 skin tumors of dogs were diagnosed in the SPV-UFRGS, totaling 2.34% of skin neoplasms in dogs. Animals that comprised the largest amount of samples (43%) were those with no breed (SRD), followed by German Shepherds (10%). Females were more affected than males (40/70 - 57% and 29/70 - 41% respectively). Skin PNST of this research showed predominant localization on the limbs (40% in the forelimbs and 29% in the hindlimbs); affecting adult dogs, mostly aged between 8 and 11 years (54%). The samples were routinely processed for hematoxylin and eosin, and were also evaluated by toluidine blue and Masson's trichrome staining, and immunohistochemistry (IHC) anti-vimentin, -S-100, -GFAP, -actin, von Willebrand factor and neurofilament. Anisocytosis and anisokaryosis, mitotic index, intratumoral necrosis, invasion of adjacent tissues, tumor location, local recurrence and metastasis were related to the diagnosis of benign (49/70) or malignant tumor (21/70). The Antoni A histological pattern was observed more frequently in benign tumors. The immunohistochemistry helped to diagnose PNST, and anti-vimentin and anti-protein S-100 showed the highest rates of immunostaining. Throughout statistical analysis of animals with tumor recurrence, it was found that the chance of an animal with a malignant peripheral nerve sheath tumor to develop recurrence is 4.61 times higher than in an animal that had a benign tumor.

RESUMO.-Mycobacterium sp. induz inflamação granulomatosa em diferentes espécies animais. Mycobacterium bovis e o complexo Mycobacterium avium são importantes pató-genos de bovinos e suínos e podem causar infecção em humanos, principalmente imunossuprimidos. Perdas na produção, barreiras comerciais e prejuízos por condenação de carcaças em abatedouro/frigorífico estão atrelados à ocorrência dessas infecções, com prejuízos econômicos signifi- Mycobacterium bovis and the Mycobacterium avium complex are important cattle and swine pathogens that can also infect humans, especially those immunosuppressed. Losses in production, commercial barriers and carcasses condemnations in slaughtering are related to this infection, which implies in large economic losses. It was carried out a study on bovine tuberculosis lesions and granulomatous lymphadenitis in pigs, diagnosed by the Setor de Patologia Veterinária from the Universidade Federal do Rio Grande do Sul (SPV-UFRGS), Brazil, between January 2007 and December 2011. Data concerning breed, sex, age and clinical history were retrieved from the files and analyzed. Histological features of the lesions in lymph nodes and lungs were evaluated in Hematoxylin-Eosin staining. Multinucleated giant cells were predominant in bovine tuberculosis lesions and epithelioid macrophages were abundant in swine. Ziehl-Neelsen and Masson's trichrome techniques were used respectively to demonstrate the alcohol-acid resistant bacillus and fibrous connective tissue in the lesions. The immunohistochemistry technique was performed to characterize the lymphocytic infiltrate. Anti-CD3 antibodies were utilized to immunolabeling lymphocytes T; and anti-CD79αcy to lymphocytes B. Lymphocytes T were predominant in both species lesions; confirmed statistically by paired t test, which showed significantly differ means of T and B lymphocytes, with t=5,501 (p<0.001) for the bovines tuberculosis lesions, and t=5.826 (p<0.001), for the cases of pigs lymphadenitis. In addition, macrophages were immunolabeled by antibody anti-CD68 to bovine, and lysozyme to swine; and polyclonal anti-Mycobacterium tuberculosis antibody were used successfully to detect Mycobacterium sp. in bovine and swine lesions, apart from in the swine samples there was also anti-Mycobacterium avium immunolabelling.INDEX TERMS: Mycobacterium spp., infectious diseases, cattle, swine, immunohistochemistry.