Luciana Sonne

Co-infection by porcine circovirus type 2 and porcine parvovirus in aborted fetuses and stillborn piglets in southern Brazil

Porcine circovirus types 1 and 2 (PCV1, PCV2) and porcine parvovirus (PPV) are widespread in pig populations around the world. Nevertheless, only PCV2 has been associated with different clinical syndromes, thus representing a major problem to the pig industry. The association of cases of swine abortions and stillborns with PCV1 and PCV2 and PPV was studied retrospectively (2005-2007). Additional pathogens were also investigated in lesioned fetuses. The studied litters included stillborn piglets and several mummified fetuses of varied sizes. Ventricular dilatation, myocardial pale areas, and mesocolic edema were the gross lesions. Escherichia coli was detected as co-infecting with PCV2 the cases in which mesocolic edema was seen. Microscopic lesions included non-suppurative myocarditis, myocardial necrosis and fibrosis, mineralization foci and intranuclear inclusion bodies in cardiomyocytes, and interstitial mononuclear pneumonia. Samples from 7 (5.78 per cent) of 121 aborted fetuses and stillborn piglets had lesions consistent with a viral cause and showed both positive anti-PCV2 immunostaining as well as PCV2-PCR. In samples from 3 (2.47 per cent) of these 7 fetuses, co-infection with PPV was confirmed by Nested-PCR. Both viruses were detected in fetuses at different stages of gestation. Viral antigens of PCV2 were detected by immunohistochemistry mainly in macrophages and myocytes. PCV1 individually was not detected in any of these affected fetuses, but it was associated with PCV2 and/or PPV in some of them. These findings indicate that PCV2 alone or in association with PPV should be kept in mind when investigating causes of infectious abortion in pigs in Brazil.

Senecio brasiliensis (Asteraceae) poisoning in Murrah buffaloes in Rio Grande do Sul 1

Descreve-se a ocorrencia de um surto de intoxicacao espontânea por Senecio brasiliensis em bufalos Murrah (Bubalus bubalis) em uma propriedade localizada no municipio de Nova Prata, Estado do Rio Grande do Sul, no periodo de junho a agosto de 2006. De um total de 90 bufalos, 13 adoeceram e 11 morreram. Os animais eram mantidos em areas de pastoreio altamente infestadas por S. brasiliensis. Os principais sinais clinicos relatados foram letargia, apatia, emagrecimento progressivo, diarreia e decubito permanente. Necropsia foi feita em dois dos 11 animais mortos. As lesoes foram caracteristicas de intoxicacoes por alcaloides pirrolizidinicos. A grande quantidade da planta, forte estiagem e desnutricao consequente foram os principais achados epidemiologicos associados com a mortalidade.

Natural Infection of Wild Canids (Cerdocyon thous and Lycalopex gymnocercus) with the Intraendothelial Piroplasm Rangelia vitalii in Southern Brazil

Abstract Rangelia vitalii is a piroplasm that infects canines, causing lesions typical of a hemolytic disorder. Two wild canids, a crab-eating fox (Cerdocyon thous) and a Pampas fox (Lycalopex gymnocercus), were presented for necropsy in Setor de Patologia Veterinária at the Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil. On gross examination, both animals had pale mucosae and moderate tick infestation (Amblyomma aureolatum). There was severe splenomegaly, and the liver had a diffusely orange-reddish lobular pattern. The mesenteric lymph nodes were brownish and slightly enlarged. Structures compatible with R. vitalii were observed in the cytoplasm of endothelial cells in the liver, stomach, heart, kidney, lungs, lymph nodes, and bladder. The agent was characterized by PCR and genetic sequencing of liver samples and ticks. We show that parasitism with R. vitalii follows an epidemiologic cycle in which wild canids act as reservoirs.

Prevalência de neoplasmas cutâneos em cães da região metropolitana de Porto Alegre, RS: 1.017 casos (2002-2007)

The aim of this study was to perform a retrospective study of cutaneous neoplasms diagnosed in dogs. The evaluation was established by analyzing the diagnostic files at the Veterinary Pathology Sector, UFRGS, Brazil, over a 6-year period (2002 to 2007). During this period a total of 1869 (37.3%) skin samples were obtained from 5016 different tissue samples of dogs submitted for examination. Among the referred skin samples, 1002 were from dogs with the diagnosis of cutaneous neoplasia and 15 dogs exhibited more than one type of skin tumor, what amounted to a total of 1017 (20.3%) cutaneous tumor samples. Results confirmed 50.5% (514/1017), 45.1% (459/1017), and 3.9% (40/1017) of respectively mesenquimal, epithelial, and melanocytic origin. Mast cell tumor was the most frequent neoplasia, diagnosed in 228 cases (22.4%), and was followed by squamous cell carcinoma (7.5%), lipoma (7.3%), perianal gland adenoma (7.1%), and trichoblastoma (5.8%). Purebred dogs such as Cocker Spaniel, Boxer, Poodle and German Sheepdog were the most representative breeds affected by various neoplasms. The data obtained, compared to data from previous studies, emphasize the variables breed, age and sex related to some skin tumors, and reinforce the importance and prevalence of different types of skin tumors in dogs.

Surto de babesiose cerebral em bovinos no Estado do Rio Grande do Sul

An outbreak of cattle mortality due to Babesia bovis infection in the county of Picada Cafe, Rio Grande do Sul, southern Brazil, in April 2007 is described. Twenty eight heifers (50.9%) died, out of a herd of 55 animals, in five days. The disease occurred approximately 20 days after heifers were transferred to this farm. The clinical signs included fever, anemia, aggressiveness, incoordination, petechiae in the mucous membranes and death after 1 to 2 days. The necropsy revealed pale mucous membranes, splenomegaly, enlarged and yellowish liver, congested and edematous gall bladder containing viscous granular bile. The kidneys and urine were dark red. The gray matter of cerebrum and cerebellum had a characteristic cherry-pink color. Hemorrhage was seen in the epicardium and endocardium. The histological findings consisted of hemoglobinuric nephrosis, paracentral hepatic necrosis, bile stasis, spleen congestion. The gray matter of the brain exhibited congestion with erythrocytes parasitized by Babesia bovis, which were also seen in the brain impression smear. The death of 28 heifers in 5 days was attributed to inadequate immunity against the parasite. The application of imidocarb dipropionate in animals presenting the initial stage of the disease and in all other animals of the herd was adopted as preventive treatment and no new cases of the disease happened in the next two months, when they were sent to slaughter.

Achados patológicos e imuno-histoquímicos em cães infectados naturalmente pelo vírus da cinomose canina

Canine distemper is a viral disease that affects mainly respiratory, gastrointestinal and nervous system. The present study analyzes pathologic and immunohistochemical findings in 54 dogs with canine distemper of a total of 760 canine necropsies performed from July 2006 to October 2007. The gross lesions were characterized by mucopurulent oculonasal discharge, hyperkeratosis of footpads, red and not collapsed lungs, thymic atrophy, watery intestinal content, hyperemia and enlarged Peyers patches. The histological findings were characterized by interstitial pneumonia, lymphoid depletion, white matter demyelization, perivascular cuffs and intracytoplasmatic and intranuclear inclusion bodies located in epithelial cells of gastric mucosa, urinary bladder, bronchial, renal pelvis, footpads, eyelid, skin of the ear, tonsil, central nervous system and mononuclear cells in lymph nodes, spleen, and tonsils. Viral antigen was detected by an immunohistochemical procedure using a mouse monoclonal anti-canine distemper antibody. The footpads were the more constantly (67.4% of the cases) immunolabeled tissue, followed by stomach with 62.7%. Immunohistochemistry was demonstrated to be a useful tool for the study of viral antigen distribution in distemper affected dogs as well as it indicated which is the best tissue to be examined in order to confirm a suspected case of canine.

OUTBREAK OF TYPE C BOTULISM IN CAPTIVE WILD BIRDS

Abstract:  In late summer 2010, an outbreak of type C botulism affected the birds kept in a dam at a southern Brazilian zoo. A total of 14 (10 black-necked swans, Cygnus melancoryphus; 3 Muscovy ducks, Cairina moschata; and 1 fulvous whistling-duck, Dendrocygna bicolor) out of 100 birds died after showing flaccid paralysis of the skeletal muscles characterized by general locomotion deficit, flight and swimming disorders, dropped neck, and severe dyspnea. Carcasses of dead birds (some infested by larvae of sarcophagus fly) scattered in the bird enclosure, and oxygen-free, organically rich mud and/or shallow standing waters present at the edges of the weir were identified as possible toxin sources. Postmortem examinations revealed no significant pathological changes. Epidemiologic and clinical findings indicated the diagnosis of type C botulism toxin, which was confirmed by mouse bioassay and seroneutralization.

Immunohistochemical study of genital and extragenital forms of canine transmissible venereal tumor in Brazil

Aiming to provide insight and discussing the problems related to the diagnosis and differential diagnosis of canine transmissible venereal tumor (CTVT), especially in its extragenital form, immunohistochemical evaluation was performed and a comparison was established by analysis of the microscopic appearance of 10 genital CTVTs and 13 exclusively extragenital CTVTs previously diagnosed by cytology and histopathology. CTVTs samples were incubated with biotinylated antibodies raised against specific membrane (anti-macrophage) and cytoplasmic antigens (anti-lysozyme, anti-S-100 protein, anti-vimentin and anti-CD18) and subsequently developed using streptavidin-biotin peroxidase and streptavidin-biotin-alkaline phosphatase methods. A strong reactivity with the anti-vimentin antibody was found in 100% of the tumors tested (22/22). No reactivity was found for the anti-lysozyme, anti-macrophage, anti-S-100 protein and anti-CD18. No histopathological or immunoreactivity differences between genital and extragenital CTVTs were found. These findings do not corroborate the hypothesis of histiocytic origin of CTVT (no reactivity to anti-lysozyme, anti-macrophage and anti-CD 18 antibodies). In addition, the antibody panel used is useful to narrow the differential diagnosis for lymphomas, histiocytic tumors, amelanotic melanomas, and poorly differentiated epithelial neoplasias, among others.

Achados clínicos e patológicos em cães infectados naturalmente por herpesvírus canino

The clinic and pathological findings and laboratorial testing of puppies with postmortem diagnosis of canine herpesvirus infection are described. The cases occurred in two households of Porto Alegre, RS, in April 2007 and July 2008. The puppies presented anorexia, depression, cry and dyspnea, followed by death about 24-72 hours after the onset of clinical signs. At necropsy multifocal pin point hemorrhages were observed in the kidneys. The liver was enlarged with petechiae and white foci on the surface. The lungs were red and did not collapse. The spleen was enlarged and, in some cases, with petechiae on the capsular surface. Mesenteric lymph nodes and thymus were enlarged. Microscopic lesions included hemorrhages and multifocal necrosis of the renal tubular epithelial cells, hepatocytes and lymphoid tissues. In the lungs there was severe multifocal alveolar necrosis with abundant fibrin deposits and a mixed inflammatory infiltrate of variable intensity. Intranuclear inclusion bodies were identified in the periphery of necrotic areas in hepatocytes, renal tubular epithelial cells and alveolar cells. Samples of liver, kidney and lung were positive in the direct immunofluorescence test for canine herpes virus type 1 (CHV-1). The diagnosis was based on epidemiological data, necropsy findings, histological lesions and positive immunofluorescence results using CHV-1 antibody in tissue samples. To our knowledge, this is the first report of the identification of CHV-1 in Brazil, although previous clinic and pathological findings already suggested the presence of the virus in Brazilian canine population.

Intoxicação por veneno de sapo em um canino

The toads of the genus Bufo produce, in their parotoid glands, a mucoid secretion containing toxins such as bufagins and Bufotoxins, which are cardiogenic steroids. The mucous membranes of dogs can absorb this venom when they attack the toads. A French bulldog with a history of probable toad venom intoxication was referred to Veterinary Pathology Section of Federal University of Rio Grande do Sul (UFRGS) for necropsy. The necropsy revealed enlarged, reddish, edematous lungs, and kidneys displaying a dark red color. The microscopic alterations indicated the presence of congestion, hemorrhage, and pulmonary edema. Congestion was observed in the kidneys, spleen and lymph nodes. The routine toxicological analyses for venom detection were negative. Nevertheless, the toad venom test result was positive as assessed by thin layer and gas chromatography, indicating that toad venom intoxication was the cause of death.