Daniele Mariath Bassuino

Natural Outbreak of BVDV-1d–Induced Mucosal Disease Lacking Intestinal Lesions

Bovine viral diarrhea virus (BVDV) belongs to the Pestivirus genus, which is further divided into subgenotypes (1a–1u and 2a–c). When persistent infection occurs, the calf will be immunotolerant to BVDV and possibly develop mucosal disease. This study describes an outbreak of BVDV-1d–induced mucosal disease lacking intestinal lesions. Eleven calves presented with anorexia, sialorrhea, lameness, recumbency, and death. Three calves were necropsied, showing ulceration of the interdigital skin and the oral and nasal mucosa; linear ulcers in the tongue, esophagus, and rumen; and rounded ulcers in the abomasum. Microscopically, mucosa and skin had superficial necrosis, with single-cell necrosis and vacuolation in epithelial cells, and severe parakeratosis. Immunohistochemistry (IHC) showed BVDV antigen in the cytoplasm of epithelial cells in skin and mucosa. All 11 dead calves were positive upon reverse transcription-polymerase chain reaction (RT-PCR) for the detection of Pestivirus along with another 11 live calves from the herd, which were positive again by RT-PCR and IHC after a 4-week interval. Sequencing of the 5′ untranslated region and N-terminal protease showed that viruses from these 22 calves were homologous and of subgenotype BVDV-1d. Cytopathic BVDV was isolated from 8 of 11 dead calves, but only noncytopathic BVDV was isolated from the 11 live animals. The findings indicate that this was an outbreak of mucosal disease caused by BVDV-1d, with high morbidity, and lesions restricted to the upper alimentary system and skin and absent from intestine. Thus, the epidemiological and pathological features in this form of mucosal disease may be similar to vesicular diseases, including foot and mouth disease.

Characterization of spinal cord lesions in cattle and horses with rabies the importance of correct sampling

Twenty-six cattle and 7 horses were diagnosed with rabies. Samples of brain and spinal cord were processed for hematoxylin and eosin staining and immunohistochemistry (IHC). In addition, refrigerated fragments of brain and spinal cord were tested by direct fluorescent antibody test and intracerebral inoculation in mice. Statistical analyses and Fisher exact test were performed by commercial software. Histologic lesions were observed in the spinal cord in all of the cattle and horses. Inflammatory lesions in horses were moderate at the thoracic, lumbar, and sacral levels, and marked at the lumbar enlargement level. Gitter cells were present in large numbers in the lumbar enlargement region. IHC staining intensity ranged from moderate to strong. Inflammatory lesions in cattle were moderate in all spinal cord sections, and gitter cells were present in small numbers. IHC staining intensity was strong in all spinal cord sections. Only 2 horses exhibited lesions in the brain, which were located mainly in the obex and cerebellum; different from that observed in cattle, which had lesions in 25 cases. Fisher exact test showed that the odds of detecting lesions caused by rabies in horses are 3.5 times higher when spinal cord sections are analyzed, as compared to analysis of brain samples alone.

Retrospective canine skin peripheral nerve sheath tumors data with emphasis on histologic, immunohistochemical and prognostic factors

Neste estudo retrospectivo foi determinada a frequencia dos tumores de bainha de nervo periferico (TBNP) na pele de caes diagnosticados pelo Setor de Patologia Veterinaria da Universidade Federal do Rio Grande do Sul (SPV-UFRGS), Brasil, no periodo de 2000 a 2012. O historico dos caes, assim como a histologia, a imuno-histoquimica e o prognostico em relacao aos tumores foram baseados em 70 amostras histologicas, correspondendo a 40 femeas (57%), 29 machos (41%) e uma amostra sem a informacao do sexo. De 2000 a 2012, foram diagnosticados 2984 tumores de pele de caes pelo SPV-UFRGS, totalizando 2,34% das neoplasias em caes. A maior parte das amostras (43%) foi proveniente de animais sem raca definida (SRD), seguidos pelos da raca Pastor Alemao (10%). A localizacao predominante dos TBNP desta pesquisa ocorreu em membros (40% em membro toracico e 29% em membro pelvico), afetando principalmente caes de oito a 11 anos idade (54%). As amostras foram processadas rotineiramente para coloracao de Hematoxilina e eosina, e foram realizadas as coloracoes de azul de toluidina e tricromio de Masson, assim como realizada imuno-histoquimica (IHQ) anti-vimentina, -S-100, -GFAP, -actina, von Willbrand e neurofilamento. Os fatores anisocitose e anisocariose, indice mitotico, necrose intratumoral, invasao tumoral em tecidos adjacentes, localizacao tumoral, local de recorrencia e metastase foram relacionados com o diagnostico de benignidade (49/70) ou malignidade (21/70). O padrao histologico de Antoni A foi observado com mais frequencia em tumores benignos. A IHQ auxiliou no diagnostico dos TBNP, com maiores indices de imunomarcacao anti-vimentina e S-100. A analise estatistica das amostras de animais que apresentaram recidiva tumoral evidenciou que a chance de um animal com tumor de bainha de nervo periferico maligno desenvolver recidiva e 4,61 vezes maior do que em animais que apresentam tumor benigno.

Novos aspectos sobre a intoxicação por Trema micrantha (Cannabaceae) em equídeos

Trema micrantha e uma planta arborea distribuida amplamente no Brasil. Descrevem-se nesse trabalho novos aspectos epidemiologicos e patologicos relacionados com a intoxicacao por essa planta em equideos. Dois equinos adultos da raca Crioula e dois asininos, de localidades distintas, foram intoxicados naturalmente por Trema micrantha, apos consumirem grande quantidade da planta que ficou disponivel a eles apos uma poda. Alem disso, um cavalo adulto, de outra propriedade, que estava passando por restricao alimentar, se intoxicou apos consumir as partes baixas de um grande numero de arvores jovens de T. micrantha. Clinicamente, em todos os equideos a doenca se caracterizou por alteracoes neurologicas, que apareceram tres a quatro dias apos o consumo da planta, com curso clinico de dois a quatro dias (abreviadas por eutanasia). Os principais achados de necropsia foram observados no figado, que estavam levemente aumentados e com padrao lobular evidente e no sistema nervoso central (SNC), com multiplas areas amareladas, focos de malacia e hemorragia, principalmente, no tronco cerebral e cerebelo. Histologicamente, havia necrose hepatica aguda, edema acentuado no SNC com degeneracao fibrinoide da parede de vasos associada a hemorragia e trombose e, frequentemente, com infiltrado de neutrofilos. Outras alteracoes observadas nos encefalos foram: grande quantidade de astrocitos de Alzheimer tipo II na substância cinzenta, acumulos de celulas Gitter e degeneracao Walleriana proxima a focos de lesoes vasculares.

Granulomatous Necrotizing Myositis in Swine Affected by Porcine Circovirus Disease

Porcine circovirus type 2 (PCV2) is associated with multiple clinical syndromes in pigs, known as porcine circovirus diseases. This work describes an outbreak of porcine circovirus diseases with severe lesions affecting the skeletal muscle. Ninety-two pigs had apathy, weight loss, and diarrhea over a clinical course of 7 to 10 days. Approximately 30 of the pigs had stiff gait, muscle weakness, hind limb paresis, and recumbency. Twelve of the 92 pigs were necropsied, and 4 had pale discoloration of skeletal muscles with microscopic lesions of granulomatous necrotizing myositis. Immunohistochemistry of skeletal muscle showed that PCV2 antigen was located primarily in the cytoplasm and nuclei of macrophages, lymphocytes, and multinucleated giant cells, with a lower amount in the cytoplasm of endothelial cells, necrotic fibers, and satellite cells. Affected muscle samples were polymerase chain reaction–positive for PCV2 and the amplicon exhibited 99% identity with sequences belonging to the PCV2b genotype. Locomotor clinical signs and granulomatous necrotizing myositis should be considered as another expression of PCV2 infection in pigs.

Equine salmonellosis in southern Brazil

The Salmonella sp. genus is identified in several species, and the zoonosis it causes is one of the most important types worldwide. The specifics of salmonellosis vary according to the function of the serovar involved, the species affected, age and predisposing factors. However, few cases of equine salmonellosis have been reported. This study presents ten confirmed salmonellosis cases in equines in southern Brazil. Six were adult animals with stress factors preceding the disease, while four were foals, three of which presented with hyperacute manifestations. The main clinical signs were diarrhea, anorexia, and hyperthermia. Lesions varied in distribution and severity, although fibrinonecrotic or necrohemorrhagic enteritis was observed in all animals, mainly in the large intestine (large colon and cecum—8/10) and small intestine (3/10). Substantial liquid content, mainly hemorrhagic, was observed in all animals. The most characteristic microscopic lesion was mucosa necrosis, which is often accompanied by fibrin deposition, followed by necrosis of follicular centers and vascular changes. Bacterial isolation revealed seven isolates. Five were serotyped, and the serovars Typhimurium and Anatum were associated with two cases each, while Muenster was associated with a case whose lesion pattern varied. Immunohistochemical staining was positive in all cases. All diagnoses were based on the clinical history, macroscopic and histological lesions, and the bacterial isolation and/or immunostaining associated with histological lesions.

Timpanismo em bovinos, secundário à obstrução esofágica por Citrus limon (limão siciliano)

Ruminal bloat (acute timpany) in ruminants is a marked rumen-reticular distension which results from more gas being produced during the physiologic process of fermentation than is eliminated by eructation. This condition may present itself as either primary timpany due to the formation of stable foam or secondary timpany resulting from functional and/or physical disturbances compromising eructation. This paper describes the epidemiological, clinical, and anatomopathological aspects of acute timpany in cattle secondary to esophageal obstruction by sicilian lemons. Five out of a herd of 210 cattle were affected. Cattle were supplemented with tangerine (Citrus reticulata) residues in a trough. In the last batch of this feed there were whole sicilian lemons mixed with the tangerine residue. The five affected cattle were 12-24 month-old Aberdeen-Angus. All of the five presented clinical signs characterized mainly by cyanotic mucous membranes, severe timpany, abdominal discomfort, marked dyspnea and tachycardia, ruminal atony, dehydration, recumbence and death. Clinical course lasted from 24 to 48 hours. Necropsy findings in the five affected cattle were similar and included complete esophageal obstruction by lemons in the cranial esophagus (immediately cranial to the larynx [1/5]) medial esophagus (at the thoracic inlet [1/5]) and caudal esophagus (close to the cardia [3/5]). At the occluded sites the esophageal mucosa was necrotic and ulcerated. Ruminal content was dried and admixed with whole lemons. In the esophagus o two affected bovine a bloat line was observed. Histological lesions were observed mainly in the esophagus at the sites of obstruction and consisted of marked degenerative, necrotic and ulcerative changes in the esophageal mucosal epithelium.

Cutaneous Pythiosis in calves: An epidemiologic, pathologic, serologic and molecular characterization

This study reports the epidemiological, pathological and mycological findings of cutaneous pythiosis in cattle in southern Brazil. 23 calves, that were kept next to a river with extensive marshy regions, presented ulcerated cutaneous lesions in thoracic and pelvic limbs, sometimes extending to the ventral thoracic region. Histopathological examination revealed multifocal pyogranulomas in the superficial and deep dermis. The Grocott-Methenamine silver, immunohistochemistry anti-Pythium insidiosum, ELISA serology and molecular characterization demonstrated the agent P. insidiosum in these cases.

Intoxicação aguda por cobre em ovinos

Cases of acute copper intoxication in Santa Ines sheep are described. The disease occurred on a farm in Rio Grande do Sul. Three ewes that had recently lambed and that were fed cattle diet became severely ill and died one week after ingestion of a commercial mineral mix for beef cattle. The sheep showed anorexia, lateral and sternal recumbency, fasciculation and muscle stiffness and death. At necropsy from one of these sheep, the main changes were moderate hepatomegaly, prominent hepatic lobular pattern, and multifocal randomly distributed erosions and ulcerations on the abomasal mucosa. Histological evaluation of the liver showed marked centrilobular hepatocellular necrosis; diffuse hepatocyte swelling predominantly in the periportal area, and a few Kupffer cells contained cytoplasmic pigment granules. The diagnosis was based on the clinical history, necropsy and histopathologic findings, and confirmed by the high copper concentrations detected in the liver, feed, and mineral mix samples.