Fábio B. Rosa

Doenças de caprinos diagnosticadas na região Central no Rio Grande do Sul: 114 casos

A retrospective study of the goat necropsies performed over a period of 48 years (1964 to 2011) at the Laboratorio de Patologia Veterinaria, Universidade Federal de Santa Maria, Rio Grande do Sul (RS) state, Brazil, was performed. A total of 114 reports of goat necropsies were analyzed. Ninety five necropsies (83.33%) had a conclusive diagnosis and 19 (19.66%) had inconclusive diagnosis. Out of the conclusive cases, infectious and parasitary diseases were the most prevalent, followed, in decreasing order of prevalence, by metabolic and nutritional diseases, poisonings and toxi-infections, and developmental diseases. Other conditions or lesions that did not fit any of the above groups of diseases affected about 10% of the necropsied goats. Hemonchosis was the most prevalent cause of death in this study. Eimeriosis and listeriosis were also important causes of goat deaths. Among the metabolic and nutritional diseases, urolithiasis, osteoporosis, pregnancy toxemia, malnutrition, and white muscle disease were the most prevalent. Mostly the infectious and parasitary diseases and the metabolic and nutritional diseases occurred many times as outbreaks, causing even more important economic losses.

Aspectos clínico-hematológicos e lesões vesicais na intoxicação crônica espontânea por Pteridium aquilinum em bovinos

Spontaneous cases of chronic poisoning by Pteridium aquilinum in cattle were studied. The clinical forms of the disease were squamous cell carcinoma (SCCs) of the upper digestive tract (UDT) and bovine enzootic hematuria (BEH). The cases were from the midland Region of the Midwest of Rio Grande do Sul State, Brazil, and were submitted to the Laboratorio de Patologia Veterinaria of the Universidade Federal de Santa Maria. Clinical signs and blood work were evaluated at terminal phase of disease. Cattle with UDT SCCs had progressive weigth loss, ruminal atony, cough, dysphagia, bloating, and regurgitation. In cattle with BEH, hematuria was observed in all cases, followed by progressive weight loss. Non-regenerative anemia was detected in 33.33% of the cattle with UDT SCCs form and in 66.66% of the cattle with BEH form. Changes in white blood count occurred in some cases but drop in lymphocyte numbers was uncommon in both forms of disease. For the morphological study, urinary bladders from 46 cattle with UDT SCCs and 11 cattle with BEH were analyzed. Grossly, 16/46 bladders from the UDT SCCs form had gross lesions (red or pale vesical nodules, hemorrhages, and papilomas; red urine was detected at necropsy of only three cases). In BEH form, the bladder had nodules, large neoplastic masses, red urine, papilomas, and hemorrhages. Pyelonephritis and hydronephrosis were seen in a few cases. Microscopically, in the UDT SCCs form, 44/46 (95.65%) bladders had 22 different types of morphological changes, characterized by neoplastic lesions (5/22) and non-neoplastic lesions (17/22); the latter were subdivided in non-neoplastic epithelial changes (6/17), general changes of the lamina propria (6/17), and inflammatory changes (5/17). The bladder changes in BEH form were of 19 different types, characterized by neoplastic lesions (5/19) and non-neoplastic lesions (14/19), which were subdivided in non-neoplastic epitelial changes (9/14), general changes of the lamina propria (3/14), and inflammatory changes (2/14). In BEH, mesenchymal neoplasms were more observed than epithelial ones, and most of them were malignant. Immunohistochemistry was utilized to characterize the histogenesis of poorly differentiated neoplasms. In conclusion, the morphological study demonstrated that urinary bladder lesions identical to the those seen in cattle with BEH, are very often present in cattle with the UDT SCCs form.Spontaneous cases of chronic poisoning by Pteridium aquilinum in cattle were studied. The clinical forms of the disease were squamous cell carcinoma (SCCs) of the upper digestive tract (UDT) and bovine enzootic hematuria (BEH). The cases were from the midland Region of the Midwest of Rio Grande do Sul State, Brazil, and were submitted to the Laboratorio de Patologia Veterinaria of the Universidade Federal de Santa Maria. Clinical signs and blood work were evaluated at terminal phase of disease. Cattle with UDT SCCs had progressive weigth loss, ruminal atony, cough, dysphagia, bloating, and regurgitation. In cattle with BEH, hematuria was observed in all cases, followed by progressive weight loss. Non-regenerative anemia was detected in 33.33% of the cattle with UDT SCCs form and in 66.66% of the cattle with BEH form. Changes in white blood count occurred in some cases but drop in lymphocyte numbers was uncommon in both forms of disease. For the morphological study, urinary bladders from 46 cattle with UDT SCCs and 11 cattle with BEH were analyzed. Grossly, 16/46 bladders from the UDT SCCs form had gross lesions (red or pale vesical nodules, hemorrhages, and papilomas; red urine was detected at necropsy of only three cases). In BEH form, the bladder had nodules, large neoplastic masses, red urine, papilomas, and hemorrhages. Pyelonephritis and hydronephrosis were seen in a few cases. Microscopically, in the UDT SCCs form, 44/46 (95.65%) bladders had 22 different types of morphological changes, characterized by neoplastic lesions (5/22) and non-neoplastic lesions (17/22); the latter were subdivided in non-neoplastic epithelial changes (6/17), general changes of the lamina propria (6/17), and inflammatory changes (5/17). The bladder changes in BEH form were of 19 different types, characterized by neoplastic lesions (5/19) and non-neoplastic lesions (14/19), which were subdivided in non-neoplastic epitelial changes (9/14), general changes of the lamina propria (3/14), and inflammatory changes (2/14). In BEH, mesenchymal neoplasms were more observed than epithelial ones, and most of them were malignant. Immunohistochemistry was utilized to characterize the histogenesis of poorly differentiated neoplasms. In conclusion, the morphological study demonstrated that urinary bladder lesions identical to the those seen in cattle with BEH, are very often present in cattle with the UDT SCCs form.

Características histomorfológicas e histoquímicas determinantes no diagnóstico da criptococose em animais de companhia

Seven cases of cryptococosis (six cats and one dog) were studied to establish the determining histomorphological and histochemical characteristics in the histopathological diagnosis of this condition. Additional data related to the epidemiology, clinical aspects, sites of the lesions, and gross findings were obtained from the necropsy and biopsy protocols. Histologically, yeasts were observed inside macrophages or free in the parenchyma, associated with scarse to severe lymphohistioplasmacytic inflammatory reaction. In the hematoxylin-eosin (HE) sections, the yeasts were round, with a central cell containing a nucleus, surrounded by a clear halo (usually non-stained capsule). The techniques of periodic Schiff acid (PAS), Groccot (GMS), and Fontana-Masson (FM) were utilized and demonstrated the wall of the yeast cells. The FM stain showed the melanin present in these cells. The Alcian blue and Mayers mucicarmin stains showed mainly the yeast polysaccharide capsule. The diameter of the cells ranged from 1.67 to 10.00µm and the full diameter of the encapsulated yeasts varied between 4.17 e 34.16µm. Yeast buddings were better observed through the PAS stain and were narrow based, simple or multiple, mainly in the opposite poles of the cells or forming chains. The definitive diagnosis of cryptococosis was established through the histopathological exam, based on the specific morphology of the agent (encapsulated yeast) and on histochemical proprieties, mostly in the cases without fungal culture.

Aspectos epidemiológicos, clinicopatológicos e imuno-histoquímicos de carcinomas de células escamosas vulvares em 33 vacas

Vulvar squamous cell carcinomas (VSCCs) in cattle were retrospectively studied regarding the prevalence, epidemiology, clinicopathological, and immunohistochemical aspects. The degree of vulvar pigmentation was also evaluated. In the 48 years analyzed, necropsy and biopsy reports of 7,483 cattle were found. Out of these, 664 (8.87%) cases of various neoplasms were identified; 33 (4.97%) of these cases were of VSCCs. Nineteen cows were Holstein, three were Charolais, one was Jersey, and 10 were mix breed cows. Grossly, the main change was vulvar swelling, with bleeding and concomitant myiasis. The tumor masses were firm, ulcerated and with yellow areas. It was possible to reevaluate microscopically 30 out of the 33 cases. Eight of them were well differentiated, 17 were moderately differentiated, and five were poorly differentiated VSCCs. The evaluation of squamous intraepithelial lesions (SILs) was performed in 21 cases. Epithelial hyperplasia was observed in 10 cases, mild dysplasia in two, moderate in one, and severe in five cases; in three cases no SILs were observed. Fontana-Masson stain for melanin was performed in 21 cases. In 17 cases the epidermal pigmentation was absent; it was mild in two and moderate in other two cases. Independently of the degree of differentiation, most neoplastic keratinocytes were strongly positive for bovine pancytokeratine through the immunohistochemistry (IHC) technique. Bovine papillomavirus was not detected by IHC in this study.

Utilização de três métodos imuno-histoquímicos na detecção de aspergilose e zigomicose em animais

Aiming to optimize the usage of the immunohistochemical technique (IHC) in the detection of Aspergillus spp. and zygomycetes (members of the Mucoraceae family), two fungal-specific monoclonal antibodies were used in tissue fragments (formalin-fixed paraffin-embedded), previously diagnosed by histomorphology as aspergillosis and zygomycosis. Tissues were submitted to three different detection systems (two biotinilated and one non biotinilated). Both antibodies showed high specificity and sensitivity in the examined tissues. No cross-reactions were observed between the antibodies used and the agents evaluated (including cases of aspergillosis, zygomycosis, candidiasis and pythiosis). However, nonspecific reactions in hyphae were observed in some cases, but were eliminated by mean of one of the detection systems used. In the aspergillosis cases, with the streptavidin-biotin-alkaline phosphatase method, nonspecific reactions were not observed. In the zygomycosis cases, nonspecific reactions did not occur using a polymer (nonbiotinilated). The IHC technique showed to be a useful tool detecting and confirming aspergillosis and zygomycosis in this retrospective study.

Enterite granulomatosa associada a larvas de ciatostomíneos em eqüinos no Rio Grande do Sul

Five cases of granulomatous enteritis associated with cyathostomes are described in horses from three farms in Rio Grande do Sul, Brazil. The cases occurred from January 1999 to December 2007. The clinical course in two cases in which clinical follow-up was available was 10-14 days. Clinical signs presented by two horses were similar and included diarrhea (3/3), weight loss (2/3), pyrexia (1/3), tachycardia (1/3), and tachypnea (1/3). Gross changes consisted of thickening of the wall of large colon and cecum by edema and the occurrence of numerous 1-4mm, dark-tan, slightly raised multifocal pinpoints disseminated throughout the mucosa. Up on the incision of these pinpoints, brown-reddish, small (1-2mm) nematode larvae emerged. Large numbers of parasites with morphology compatible with small strongyles were observed in the lumina of large colon and cecum or adhered to the mucosae of these organs. Histologically, multiple granulomas were seen in the mucosa and submucosa of large colon and cecum. These granulomas consisted of moderate to severe inflammatory infiltrate of macrophages, epithelioid macrophages, and eosinophils surrounded by fewer lymphocytes and plasma cells. In the center of these granulomas, transversal cut sections of parasites with morphology compatible with cyathostomes larvae were observed. Additionally, there was edema and moderate to marked lymphohistioplasmacytic and eosinophilic inflammatory infiltrate throughout the mucosa and submucosa of the large colon and cecum; necrosis and lymphohistiocytic proliferation in the submucosal lymphoid follicles, with hyperplasia of goblet cells in the epithelial lining of these organs were also observed. The diagnosis of granulomatous enteritis associated with larval cyathostomiasis was made based on epidemiological, clinical, and gross findings which were confirmed by histopathology.

Epidemiologia e distribuição de lesões extrarrenais de uremia em 161 cães

The aim of this study was to determine the epidemiology and the morphological characteristics (including the anatomic localization) of the extrarenal uremic lesions, as well as to describe the main lesions of the urinary system associated with the occurrence of uremia, through analysis of the protocols of necropsies performed in dogs from January 1996 to December 2012 (17 years) at the Laboratorio de Patologia Veterinaria of the Universidade Federal de Santa Maria. A total of 4,201 dogs were necropsied and 161 (3.8%) had extrarenal uremic lesions. In 134 dogs (83.2%) clinical signs associated with uremia were reported. The extrarenal lesions more often observed, in descending order of prevalence, were ulcerative and hemorrhagic gastritis (56.5%), soft-tissue mineralization (55.9%), pulmonary edema (47.2%), ulcerative stomatitis and/or glossitis (30.4%), endocarditis/atrial and aortic thrombosis (28.6%), parathyroid hyperplasia (9.3%), fibrous osteodystrophy (8.1%), anemia (6.2%), ulcerative laryngitis (5%), ulcerative and hemorrhagic enteritis (3.7%), fibrinonecrotic esophagitis (1.9%), and fibrinous pericarditis (1.9%). In most of the cases, the extrarenal lesions of uremia were due to prolonged azotemia secondary to severe renal lesions, such as interstitial nephritis and glomerulonephritis (the most prevalent ones).

Osteoporose em caprinos

A study of cases of osteoporosis in goats diagnosed in the Laboratorio de Patologia Veterinaria, Universidade Federal de Santa Maria, Rio Grande do Sul state, Brazil, was performed. The epidemiology, clinicopathological changes and possible pathogenetic mechanisms were determined and discussed. Five goats, females, mixed breed, with six months to six years of age were affected. The goats were kept on natural pasture without supplemental feed and under overcrowding condition. The main clinical signs were weight loss, limited mobility, and recumbence for long periods. The main gross bone changes, observed on the cutting surface, were depletion of cancellous bone (porosity) and marked reduction in the thickness of the cortical bone. Severe serous atrophy of medullary adipose tissue was also observed. Microscopically, in the evaluated regions (proximal humerus, distal radius, distal femur, proximal tibia and lumbar vertebral bodies), moderate to marked reduction in the number and thickness of bone trabeculae in the epiphyses and metaphyses of long bones and in the vertebral bodies were observed. The clinicopathological features indicated that the osteoporosis observed was probably caused by malnutrition. The bone changes (decrease in the number and thickness of trabeculae of cancellous bone) suggest that both mechanisms, poor bone formation and increased bone resorption, contributed to the occurrence of osteoporosis in the goats of this study.

Relação entre a linfopenia e a persistência da papilomatose alimentar em bovinos intoxicados crônica e espontaneamente por samambaia (Pteridium aquilinum)

Papilomavirus bovino tipo 4 (BPV-4) e responsavel pelo desenvolvimento de papilomas no trato alimentar superior (TAS) de bovinos. Os passos necessarios para o crescimento, o desenvolvimento e a regressao dos papilomas estao intimamente relacionados com o estado imunologico do animal. A ingestao de samambaia (Pteridium aquilinum) tem sido relacionada como o principal fator envolvido na persistencia da infeccao pelo BPV-4 no TAS. A teoria que estabelece a relacao entre papilomatose alimentar e a formacao de CCEs sugere a producao de um estado imunossupressivo cronico pela planta, permitindo a persistencia dos papilomas no TAS. Os papilomas serviriam entao como sitios de desenvolvimento dos CCEs atraves da interacao entre as proteinas do BPV-4 e os carcinogenos da samambaia. O objetivo deste estudo foi avaliar a relacao entre a quantidade de linfocitos circulantes e a papilomatose alimentar em casos de intoxicacao espontânea cronica por P. aquilinum em bovinos com CCE no TAS. Quarenta bovinos com CCEs no TAS foram avaliados quanto a idade, a intensidade da papilomatose alimentar no TAS e ao leucograma. Tres bovinos tinham leucopenia e um apresentava neutrofilia. A media de linfocitos foi de 5.395 (±1.696) na papilomatose leve, 4.560 (±1.561) na moderada e 5.007 (±1.786) na acentuada. Nao houve diferenca estatisticamente significativa entre o grau de papilomatose, a idade e a quantidade de linfocitos circulantes. Imunossupressao por linfopenia foi um achado esporadico (tres casos) neste estudo. Os resultados indicam que a persistencia da papilomatose alimentar em casos espontâneos de intoxicacao cronica por samambaia em bovinos nao tem relacao com a quantidade de linfocitos circulantes e que talvez esteja relacionada a outros fatores imunologicos.

Spontaneous poisoning by Brachiaria decumbens in goats

An outbreak of Brachiaria decumbens poisoning in goats in the state of Mato Grosso do Sul, Brazil, is described. Out of a herd of about 1,000 goats, seven goats died after showing photosensitivity (3 out 7 goats) and icterus (4/7). Other clinical signs included lethargy, dehydration and weight loss (7/7). At necropsy there was either hepatomegaly or liver atrophy; orange, yellow or gray discoloration - were observed in the liver of six goats. Two had accentuation of lobular pattern and punctate, linear or stellar fibrous depressions were randomly distributedover the capsular surface. Macroscopic changesattributedto liver failure consisting of hydropericardium (2/7) and ascites (2/7) were observed. Histologically, there was accumulation of refringent crystals in the bile ducts and infiltration of foamy macrophages in the liver of all goats. Foamy macrophages were also present in the hepatic and mesenteric lymph nodes of two goats. The diagnosis of B. decumbens poisoning was based on epidemiology, clinical signs, necropsy findings and histopathology.