Neuropathology of natural canid alphaherpesvirus 1 infection in dogs

The neuropathology of canid alphaherpesvirus 1 (CaHV-1) infection in dogs has been reported, but the importance of the cerebellar lesions in the routine diagnosis remains relatively understated in the veterinary literature. Here we characterize the neuropathology of natural CaHV-1 infection in 25 dogs. The disease affected predominantly male dogs (22 cases). Clinical signs in 15 cases varied and sudden death was reported in 10 cases. All dogs had the typical areas of necrosis and hemorrhage in multiple organs with eosinophilic intranuclear viral inclusions in epithelial and/or inflammatory cells in multiple organs in 21 cases. Cerebral swelling and reddening were reported in 3 cases. Neurohistologic changes consisted of mild lymphoplasmacytic meningoencephalitis with occasional vasculitis and widespread glial nodules. Rare intranuclear viral inclusions (4 cases) were observed in endothelial cells or inflammatory cells in glial nodules. Cerebellum was examined in 11 cases and had extensive segmental necrosis of Purkinje cell layer (8 cases) and granule neurons in the internal (9 cases) or external (2 cases) granular cell layer. Intranuclear viral inclusions were observed in 8 cases and occurred in necrotic granule neurons in the inner granular cell layer (7 cases), outer granular cell layer (2 cases), Purkinje neurons (1 case), or endothelial cells (1 case). Diagnostic confirmation in 23 cases was based on routine histology and fluorescent antibody testing for CaHV-1 on fresh or frozen tissue samples. A routine diagnosis was based solely on the visualization of intranuclear viral inclusions in 2 cases.(AU)

Cutaneous apocrine adenocarcinoma in a goat

Apocrine neoplasms are rare in goats. This report describes an apocrine adenocarcinoma in a 5-year-old female Boer goat with an ulcerated, exophytic, multilobulated mass on the left dorsolateral cervical area. Histologically, the dermis was effaced and expanded by a poorly demarcated epithelial neoplasm with desmoplasia. Neoplastic cells were arranged in acini with papillary projections into the lumen and had cuboidal or columnar, eosinophilic, occasionally vacuolated cytoplasm. Nuclei were round and had finely stippled chromatin with one nucleolus. Neoplastic cells contained periodic acid-Schiff (PAS)­positive and diastase­resistant, alcian blue­positive cytoplasmic granules. There were 6 mitoses in 2.37 mm2 (equivalent to 10 FN22/40X fields). Histologic and histochemical features in the current case were consistent with a cutaneous apocrine gland adenocarcinoma.(AU)

Down the rabbit hole: a quick guide for histopathology description

ABSTRACT: Histopathology is an old science that is still currently utilized for disease diagnosis and research. The routinely processed histologic slides stained with hematoxylin and eosin are still used worldwide in most if not every histopathology laboratory. The technique is inexpensive, quick to perform, and allows the diagnosis of a fantastic variety of tissue changes and diseases. Skills in description and interpretation in histopathology are a craft that can be learned by repeatedly and systematically observing simple rules. In this article, we offer a few advices to help trainees in veterinary pathology at the start of their careers. Those advices are drawn from our experience in the diagnostic pathology routine and from the veterinary pathology literature. To enhance the understanding of these important steps in the histopathologic description of tissues, we decided to illustrate most concepts expressed here. We hope that our effort can add a bit to the development of future pathologists. Just like Alice, let us follow the White Rabbit into his burrow for this challenging experience!

RESUMO: A histopatologia é uma ciência antiga, mas ainda usada para diagnosticar e investigar a patogênese de doenças. As lâminas histológicas processadas rotineiramente e coradas por hematoxilina e eosina ainda são utilizadas em virtualmente todos os laboratórios de histopatologia do mundo. A técnica não é cara, é de execução rápida e permite o diagnóstico de uma fantástica variedade de doenças. As habilidades em descrever e interpretar os achados histopatológicos é um ofício que pode ser aprendido pela observação repetida e sistemática de regras simples. Para ajudar os estudantes de patologia no início de suas carreiras, abordamos aqui algumas dessas regras, extraídas tanto de nossa experiência quanto da literatura relacionada à patologia veterinária. Para aumentar a compreensão dos tópicos, decidimos ilustrar praticamente todos os conceitos expressados neste manuscrito. Esperamos que nosso esforço possa contribuir um pouco para o desenvolvimento de aspirantes a patologistas. Assim como Alice no País das Maravilhas, vamos seguir o coelho branco até a sua toca para essa aventura desafiadora.

Down the rabbit hole: a quick guide for histopathology description / Descendo a toca do coelho: um guia rápido para descrição histopatológica

Histopathology is an old science that is still currently utilized for disease diagnosis and research. The routinely processed histologic slides stained with hematoxylin and eosin are still used worldwide in most if not every histopathology laboratory. The technique is inexpensive, quick to perform, and allows the diagnosis of a fantastic variety of tissue changes and diseases. Skills in description and interpretation in histopathology are a craft that can be learned by repeatedly and systematically observing simple rules. In this article, we offer a few advices to help trainees in veterinary pathology at the start of their careers. Those advices are drawn from our experience in the diagnostic pathology routine and from the veterinary pathology literature. To enhance the understanding of these important steps in the histopathologic description of tissues, we decided to illustrate most concepts expressed here. We hope that our effort can add a bit to the development of future pathologists. Just like Alice, let us follow the White Rabbit into his burrow for this challenging experience!(AU)

A histopatologia é uma ciência antiga, mas ainda usada para diagnosticar e investigar a patogênese de doenças. As lâminas histológicas processadas rotineiramente e coradas por hematoxilina e eosina ainda são utilizadas em virtualmente todos os laboratórios de histopatologia do mundo. A técnica não é cara, é de execução rápida e permite o diagnóstico de uma fantástica variedade de doenças. As habilidades em descrever e interpretar os achados histopatológicos é um ofício que pode ser aprendido pela observação repetida e sistemática de regras simples. Para ajudar os estudantes de patologia no início de suas carreiras, abordamos aqui algumas dessas regras, extraídas tanto de nossa experiência quanto da literatura relacionada à patologia veterinária. Para aumentar a compreensão dos tópicos, decidimos ilustrar praticamente todos os conceitos expressados neste manuscrito. Esperamos que nosso esforço possa contribuir um pouco para o desenvolvimento de aspirantes a patologistas. Assim como Alice no País das Maravilhas, vamos seguir o coelho branco até a sua toca para essa aventura desafiadora.(AU)

Down the rabbit hole: a quick guide for histopathology description / Descendo a toca do coelho: um guia rápido para descrição histopatológica

Histopathology is an old science that is still currently utilized for disease diagnosis and research. The routinely processed histologic slides stained with hematoxylin and eosin are still used worldwide in most if not every histopathology laboratory. The technique is inexpensive, quick to perform, and allows the diagnosis of a fantastic variety of tissue changes and diseases. Skills in description and interpretation in histopathology are a craft that can be learned by repeatedly and systematically observing simple rules. In this article, we offer a few advices to help trainees in veterinary pathology at the start of their careers. Those advices are drawn from our experience in the diagnostic pathology routine and from the veterinary pathology literature. To enhance the understanding of these important steps in the histopathologic description of tissues, we decided to illustrate most concepts expressed here. We hope that our effort can add a bit to the development of future pathologists. Just like Alice, let us follow the White Rabbit into his burrow for this challenging experience!(AU)

A histopatologia é uma ciência antiga, mas ainda usada para diagnosticar e investigar a patogênese de doenças. As lâminas histológicas processadas rotineiramente e coradas por hematoxilina e eosina ainda são utilizadas em virtualmente todos os laboratórios de histopatologia do mundo. A técnica não é cara, é de execução rápida e permite o diagnóstico de uma fantástica variedade de doenças. As habilidades em descrever e interpretar os achados histopatológicos é um ofício que pode ser aprendido pela observação repetida e sistemática de regras simples. Para ajudar os estudantes de patologia no início de suas carreiras, abordamos aqui algumas dessas regras, extraídas tanto de nossa experiência quanto da literatura relacionada à patologia veterinária. Para aumentar a compreensão dos tópicos, decidimos ilustrar praticamente todos os conceitos expressados neste manuscrito. Esperamos que nosso esforço possa contribuir um pouco para o desenvolvimento de aspirantes a patologistas. Assim como Alice no País das Maravilhas, vamos seguir o coelho branco até a sua toca para essa aventura desafiadora.(AU)

Uterine leiomyosarcoma with secondary acute hemoabdomen in a goat

Neoplasms of the reproductive tract are uncommonly reported in goats. Here we describe a case of sudden death caused by acute hemoabdomen due to a ruptured uterine leiomyosarcoma in a 7-year-old female mixed breed goat. Gross changes included oral and ocular pallor, as well as 3 liters of blood and blood clots in the abdominal cavity. The uterine body wall was irregularly thickened and firm, and had a 2 cm in diameter, transmural perforation. The uterine lumen was filled with dark red to brown blood clots admixed with friable necrotic material. Histologically, a poorly-demarcated neoplasm expanded and effaced the uterine wall. The neoplasm consisted of densely packed bundles and streams of elongate neoplastic cells with moderate pleomorphism and abundant eosinophilic cytoplasm and elongate nuclei with coarsely stippled chromatin. The mitotic count was 4 per 2.37 mm2. Multiple areas of necrosis and clusters of lymphocytes and plasma cells were present throughout the neoplasm. Neoplastic cells exhibited diffuse immunolabeling for smooth muscle actin and patchy immunolabeling for desmin, consistent with a uterine leiomyosarcoma.(AU)

Ulcerative dermatitis due to feline infectious peritonitis virus infection in a cat

Feline infectious peritonitis (FIP) is one of the most prevalent viral diseases of wild and domestic cats. Despite of its multisystemic character, cutaneous lesions of FIP have been rarely described. A skin biopsy from a 14-month-old maleneutered domestic shorthaired cat with a slightly raised, 5 mm in diameter ulcer on the dorsal cervical area and apresumptive clinical diagnosis of FIP was submitted for histological examination. Histological changes consisted of ulcerative dermatitis with perivascular, periadnexal, and interstitial accumulations of neutrophils, macrophages, lymphocytes, and plasma cells with areas of vasculitis. Immunohistochemistry for feline coronavirus revealed intralesional clusters of antigen within macrophages. FIP should be considered in cases of papular to nodular or ulcerative skin lesions in cats when occurring in conjunction with clinical signs of systemic disease consistent with FIP.

Uterine leiomyosarcoma with secondary acute hemoabdomen in a goat

Neoplasms of the reproductive tract are uncommonly reported in goats. Here we describe a case of sudden death caused by acute hemoabdomen due to a ruptured uterine leiomyosarcoma in a 7-year-old female mixed breed goat. Gross changes included oral and ocular pallor, as well as 3 liters of blood and blood clots in the abdominal cavity. The uterine body wall was irregularly thickened and firm, and had a 2 cm in diameter, transmural perforation. The uterine lumen was filled with dark red to brown blood clots admixed with friable necrotic material. Histologically, a poorly-demarcated neoplasm expanded and effaced the uterine wall. The neoplasm consisted of densely packed bundles and streams of elongate neoplastic cells with moderate pleomorphism and abundant eosinophilic cytoplasm and elongate nuclei with coarsely stippled chromatin. The mitotic count was 4 per 2.37 mm2. Multiple areas of necrosis and clusters of lymphocytes and plasma cells were present throughout the neoplasm. Neoplastic cells exhibited diffuse immunolabeling for smooth muscle actin and patchy immunolabeling for desmin, consistent with a uterine leiomyosarcoma.

Ulcerative dermatitis due to feline infectious peritonitis virus infection in a cat

Feline infectious peritonitis (FIP) is one of the most prevalent viral diseases of wild and domestic cats. Despite of its multisystemic character, cutaneous lesions of FIP have been rarely described. A skin biopsy from a 14-month-old maleneutered domestic shorthaired cat with a slightly raised, 5 mm in diameter ulcer on the dorsal cervical area and apresumptive clinical diagnosis of FIP was submitted for histological examination. Histological changes consisted of ulcerative dermatitis with perivascular, periadnexal, and interstitial accumulations of neutrophils, macrophages, lymphocytes, and plasma cells with areas of vasculitis. Immunohistochemistry for feline coronavirus revealed intralesional clusters of antigen within macrophages. FIP should be considered in cases of papular to nodular or ulcerative skin lesions in cats when occurring in conjunction with clinical signs of systemic disease consistent with FIP.(AU)

Nephroblastoma in a black-tufted marmoset (Callithrix penicillata) / Nefroblastoma em um sagui-de-tufos-pretos (Callithrix penicillata)

A renal nephroblastoma is described in a free-living black-tufted marmoset (Callithrix penicillata) in Central Brazil. The monkey was found dead and subjected to necropsy. Gross anatomic changes consisted of a ruptured left kidney, which was almost completely effaced by a white to yellow, partially encapsulated friable mass. The left ureter was distended due to obstruction by a red, spherical, 2mm in diameter friable mass. The urinary bladder was also distended. Histologically the renal and ureteral masses consisted of a triphasic embryonal neoplasm composed of embryonic epithelium forming glomeruli and tubules, polygonal blastemal cells, and a mesenchymal stroma. The embryonic epithelium exhibited rare nuclear immunoreactivity for WT-1, whereas blastemal cells exhibited robust cytoplasmic and rare nuclear immunoreactivity for WT-1; blastemal cells were also immunoreactive for vimentin. No immunoreactivity was detected for pan-cytokeratin (AE1/AE3), actin, and desmin. Morphological and immunohistochemical features of the present neoplasm are consistent with those described for renal nephroblastoma.(AU)

Descreve-se um caso de nefroblastoma maligno em um sagui de vida livre no Brasil Central. O macaco foi encontrado morto e encaminhado para necropsia. Na macroscopia, o rim esquerdo apresentava-se rompido e o parênquima estava substituído por um tecido neoplásico friável, parcialmente encapsulado e de superfície natural branca e de corte amarela. O ureter esquerdo apresentava-se distendido devido à obstrução por uma massa friável, vermelha, esférica, de 2mm de diâmetro. Histologicamente, as massas renal e ureteral consistiam de uma neoplasia embrionária composta por três populaçõies de células neoplásicas, composta por epitélio embrionário formando glomérulos e túbulos, células blastemais poligonais e um estroma mesenquimal. O epitélio embrionário exibiu imunorreactividade nuclear rara para WT-1, enquanto que as células blastemais exibiram imunorreactividade nuclear citoplasmática e rara para WT-1; As células blastemais também foram imunorreativas à vimentina. Nenhuma imunorreatividade foi detectada para pan-citoqueratina (AE1/AE3), actina e desmina. As características morfológicas e imuno-histoquímicas da presente neoplasia são consistentes com as descritas para o nefroblastoma renal.(AU)

Nephroblastoma in a black-tufted marmoset (Callithrix penicillata) / Nefroblastoma em um sagui-de-tufos-pretos (Callithrix penicillata)

A renal nephroblastoma is described in a free-living black-tufted marmoset (Callithrix penicillata) in Central Brazil. The monkey was found dead and subjected to necropsy. Gross anatomic changes consisted of a ruptured left kidney, which was almost completely effaced by a white to yellow, partially encapsulated friable mass. The left ureter was distended due to obstruction by a red, spherical, 2mm in diameter friable mass. The urinary bladder was also distended. Histologically the renal and ureteral masses consisted of a triphasic embryonal neoplasm composed of embryonic epithelium forming glomeruli and tubules, polygonal blastemal cells, and a mesenchymal stroma. The embryonic epithelium exhibited rare nuclear immunoreactivity for WT-1, whereas blastemal cells exhibited robust cytoplasmic and rare nuclear immunoreactivity for WT-1; blastemal cells were also immunoreactive for vimentin. No immunoreactivity was detected for pan-cytokeratin (AE1/AE3), actin, and desmin. Morphological and immunohistochemical features of the present neoplasm are consistent with those described for renal nephroblastoma.(AU)

Descreve-se um caso de nefroblastoma maligno em um sagui de vida livre no Brasil Central. O macaco foi encontrado morto e encaminhado para necropsia. Na macroscopia, o rim esquerdo apresentava-se rompido e o parênquima estava substituído por um tecido neoplásico friável, parcialmente encapsulado e de superfície natural branca e de corte amarela. O ureter esquerdo apresentava-se distendido devido à obstrução por uma massa friável, vermelha, esférica, de 2mm de diâmetro. Histologicamente, as massas renal e ureteral consistiam de uma neoplasia embrionária composta por três populaçõies de células neoplásicas, composta por epitélio embrionário formando glomérulos e túbulos, células blastemais poligonais e um estroma mesenquimal. O epitélio embrionário exibiu imunorreactividade nuclear rara para WT-1, enquanto que as células blastemais exibiram imunorreactividade nuclear citoplasmática e rara para WT-1; As células blastemais também foram imunorreativas à vimentina. Nenhuma imunorreatividade foi detectada para pan-citoqueratina (AE1/AE3), actina e desmina. As características morfológicas e imuno-histoquímicas da presente neoplasia são consistentes com as descritas para o nefroblastoma renal.(AU)

Cystitis and peritonitis caused by Staphylococcus xylosus infection in a calf

Staphylococcus xylosus is a Gram-positive coagulase-negative staphylococcus with hemolytic activity and ability to form biofilms. This organism can be a component of the human skin microbiome, with rare reported cases of opportunistic infections. S. xylosus can be also isolated from the skin of healthy cattle, horses, pigs, dogs, laboratory mice, chickens, and pigeons. Reports of disease caused by S. xylosus are rare in veterinary medicine, with cases of bovine and ovine mastitis and dermatitis, and pneumonia in immunocompromised laboratory mice. This report describes the first case of transmural necrotizing cystitis and secondary peritonitis caused by S. xylosus in a 4-month-old male Holstein calf with a history of acute onset of recumbency and spontaneous death. Gross necropsy findings included marked urinary bladder distention and diffuse reddening, and large amounts of dark red, hemorrhagic contents. In addition, segments of small intestine and mesentery were adhered to the urinary bladder. Histological evaluation revealed transmural necrosuppurative cystitis with secondary peritonitis and intralesional Gram-positive and fewer Gram-negative cocci. Bacterial culture of urine samples yielded heavy growth of S. xylosus.(AU)

Cystitis and peritonitis caused by Staphylococcus xylosus infection in a calf

Staphylococcus xylosus is a Gram-positive coagulase-negative staphylococcus with hemolytic activity and ability to form biofilms. This organism can be a component of the human skin microbiome, with rare reported cases of opportunistic infections. S. xylosus can be also isolated from the skin of healthy cattle, horses, pigs, dogs, laboratory mice, chickens, and pigeons. Reports of disease caused by S. xylosus are rare in veterinary medicine, with cases of bovine and ovine mastitis and dermatitis, and pneumonia in immunocompromised laboratory mice. This report describes the first case of transmural necrotizing cystitis and secondary peritonitis caused by S. xylosus in a 4-month-old male Holstein calf with a history of acute onset of recumbency and spontaneous death. Gross necropsy findings included marked urinary bladder distention and diffuse reddening, and large amounts of dark red, hemorrhagic contents. In addition, segments of small intestine and mesentery were adhered to the urinary bladder. Histological evaluation revealed transmural necrosuppurative cystitis with secondary peritonitis and intralesional Gram-positive and fewer Gram-negative cocci. Bacterial culture of urine samples yielded heavy growth of S. xylosus.

Mixed apocrine adenocarcinoma of the tail in a cow

This report describes an uncommon case of neoplasm in domesticated animals, mixed apocrine adenocarcinoma (MAA). A cutaneous mass from the tail and anal region of an adult cow was detected during the routine antemortem examination of cattle in a slaughterhouse. The mass was ulcerated, firm, measured 23 x 20 x 20 cm and weighed 10 Kg. There were extensive areas of hemorrhage and necrosis admixed with irregular islands of bone. Histopathological examination revealed multiple cysts with papillary projections into lumen. Periodic acid-Schiff (PAS) reaction revealed amorphous eosinophilic secretory material into luminal spaces and on the apical surface of neoplastic cells. Immunohistochemical investigation revealed strong cytoplasmic immunostaining of the epithelial neoplastic cells for cytokeratin 19 (CK19) and strong positive immunostaining of the myoepithelial cells for smooth muscle actin (SMA) and S-100 protein. These gross and histopathological findings observed during this study led to a final diagnosis of MAA.

Mixed apocrine adenocarcinoma of the tail in a cow

This report describes an uncommon case of neoplasm in domesticated animals, mixed apocrine adenocarcinoma (MAA). A cutaneous mass from the tail and anal region of an adult cow was detected during the routine antemortem examination of cattle in a slaughterhouse. The mass was ulcerated, firm, measured 23 x 20 x 20 cm and weighed 10 Kg. There were extensive areas of hemorrhage and necrosis admixed with irregular islands of bone. Histopathological examination revealed multiple cysts with papillary projections into lumen. Periodic acid-Schiff (PAS) reaction revealed amorphous eosinophilic secretory material into luminal spaces and on the apical surface of neoplastic cells. Immunohistochemical investigation revealed strong cytoplasmic immunostaining of the epithelial neoplastic cells for cytokeratin 19 (CK19) and strong positive immunostaining of the myoepithelial cells for smooth muscle actin (SMA) and S-100 protein. These gross and histopathological findings observed during this study led to a final diagnosis of MAA.(AU)

Anaplastic Ventricular Adenocarcinoma in a Blue and Gold Macaw (Ara ararauna)

A case of anaplastic ventricular adenocarcinoma in an adult, female captive blue and gold macaw (Ara ararauna) is reported. The bird died suddenly and was submitted to necropsy. The carcass was in poor body condition. A pale, firm neoplastic mass was observed infiltrating the wall of the proventricular-ventricular junction. Histologically, the neoplasm consisted of a poorly demarcated and highly invasive proliferation of cuboidal to columnar neoplastic epithelial cells arranged into small groups and admixed with a dense desmoplastic reaction. Numerous neoplastic cells showed a finely fibrillar, Alcian blue-positive cytoplasmic material. Neoplastic cells were strongly positive for pancytokeratin and negative for vimentin. The diagnosis of anaplastic ventricular adenocarcinoma was based on histological, histochemical, and immunohistochemical findings. These neoplasms are uncommon in psittacine birds and to the best of our knowledge have not been reported in this species.(AU)

Surto de ceratoconjuntivite infecciosa bovina e hemoncose causando mortalidade em bezerros / Outbreak of infectious bovine keratoconjunctivitis and haemonchosis causing moratality in calves

É descrito um surto de ceratoconjuntivite infecciosa bovina (CIB) e hemoncose intercorrente afetando um grupo de 116 bezerros de 1-2 anos de idade na região central do Rio Grande do Sul. Vinte bezerros foram afetados e nove morreram. Os sinais clínicos incluíam perda de peso, marcada palidez da mucosa oral, lacrimejamento, opacidade focal da córnea e avermelhamento da conjuntiva. Sinais mais avançados incluíam lacrimejamento copioso, opacidade da córnea, ceratocone, ceratomalacia e cegueira. O diagnóstico de CIB foi baseado nos achados epidemiológicos e clínico-patológicos e confirmado pela cultura de uma cepa hemolítica de Moraxella bovis dos olhos de dois terneiros afetados. O alto coeficiente de letalidade (45 por cento) neste surto foi atribuído a grave hemoncose intercorrente.(AU)

An outbreak of infectious bovine keratoconjunctivitis (IBK) with concomitant haemonchosis is described affecting a group of 116 yearling calves in southern Brazil. Twenty calves were affected and nine died. Clinical signs included wasting, marked oral mucosal pallor, serous ocular discharge, focal central corneal opacity, and reddening of the conjunctiva. More advanced stages displayed copious serous ocular discharge, corneal opacity, keratoconus, keratomalacia, and blindness. The diagnosis of IBK was based on the epidemiological, clinical, and pathological findings and confirmed by bacteriologic culture of a hemolytic strain of Moraxella bovis from the eye globe of two affected calves. The high lethality rate (45 percent) in this outbreak was caused by concomitant and severe haemonchosis.(AU)

Intoxicação espontânea por antibióticos ionóforos em ovinos no Rio Grande do Sul / Spontaneous poisoning by ionophores in sheep in Rio Grande do Sul, Brazil

Um surto de intoxicação espontânea por antibióticos ionóforos em ovinos da região Central do Rio Grande do Sul é descrito. Os 16 ovinos afetados estavam em campo nativo e ingeriram acidentalmente um aditivo alimentar para frangos contendo 250g/kg de narasina. Os sinais clínicos consistiam de fraqueza, incoordenação, dispnéia, secreção nasal, decúbito e morte em poucas horas. Um ovino apresentou urina escura. Macroscopicamente havia ascite, hidrotórax, edema pulmonar e palidez hepática. Discreto grau de degeneração muscular na musculatura esquelética dos membros pélvicos e torácicos foi observado histologicamente. O diagnóstico de intoxicação por narasina foi realizado com base no histórico (ingestão de aditivo alimentar contendo narasina) e nos achados clinico-patológicos.(AU)

An outbreak of spontaneous ionophore toxicity in sheep grazing in native pasture in Rio Grande do Sul state, Brazil is described. Sixteen sheep which had accidental access to a chicken feed additive containing 250g/kg of narasin were affected. Clinical signs consisted of weakness, incoordination, dyspnea, nasal discharge, recumbency, and death in a few hours. One sheep showed dark red urine. Grossly there were ascites, hydrothorax, pulmonary edema, and hepatic paleness. Discrete skeletal muscle degeneration was observed histologically in the muscles of the pelvic and thoracic limbs. The diagnostic of narasin toxicosis was based on history (ingestion of feed additive containing narasin), clinical, and pathological findings.(AU)

Doenças neurológicas de ovinos na região central do Rio Grande do Sul / Neurological diseases in sheep from central Rio Grande do Sul state, southern Brazil

Neste trabalho são descritos aspectos epidemiológicos e clinico-patológicos das principais doenças neurológicas de ovinos diagnosticadas no Laboratório de Patologia Veterinária (LPV) da Universidade Federal de Santa Maria (UFSM) no período entre 1990 e 2007. A partir de uma busca nos arquivos do LPV-UFSM foram encontrados 586 exames de ovinos correspondentes a necropsias realizadas no laboratório ou a exames de amostras remetidas por veterinários de campo. Sessenta e nove casos experimentais foram excluídos do estudo. Os 517 casos restantes eram compostos de 361 casos (69,8 por cento) com diagnóstico conclusivo e 156 casos (30,2 por cento) com diagnóstico inconclusivo. Ovinos morreram em decorrência de doença neurológica em 58 casos (16 por cento) do grupo com diagnóstico conclusivo. As doenças diagnosticadas mais frequentemente foram cenurose (15 casos ou 25,8 por cento), listeriose (nove casos ou 15,5 por cento), tétano (oito casos ou 13,7 por cento), abscessos vertebrais (quatro casos ou 6,8 por cento) e abscessos encefálicos (três casos ou 5,1 por cento). Intoxicação por Erytroxylum argentinum, mielite supurativa pós-caudectomia, meningoencefalite fibrino-supurativa, polioencefalomalacia e raiva (dois casos ou 3,4 por cento cada) foram ocasionalmente diagnosticadas. Desmielinização medular, edema da substância branca encefálica, encefalomalacia focal simétrica, hidranencefalia, hipoplasia cerebelar, intoxicação por organofosforado, intoxicação por Solanum pseudocapsicum, mielite fibrino-supurativa e provável intoxicação por closantel (um caso ou 1,7 por cento cada) foram raramente observadas.(AU)

A retrospective study of neurological diseases of sheep in southern Brazil was conducted over an 18-year period (1990-2007). A data base search was carried out in the files of the Laboratory of Veterinary Pathology (LPV) of the Universidade Federal de Santa Maria (UFSM), central Rio Grande do Sul state, Brazil. A total of 586 sheep were examined. These cases corresponded to necropsies performed in the LPV-UFSM or to mailed in samples from practitioners. Out of these, 69 experimental cases were excluded from this study. The remaining 517 cases were composed of 361 (69.8 percent) cases with conclusive diagnoses and 156 (30.2 percent) cases with inconclusive diagnoses. In 58 (16 percent) occasions, sheep died in consequence of neurological disease. Most important diseases included coenurosis (15 cases or 25.8 percent), listeriosis (9 cases or 15.5 percent), tetanus (8 cases or 13.7 percent), vertebral abscesses (4 cases or 6.8 percent), and cerebral abscesses (3 cases or 5.1 percent). Poisoning by Erytroxylum argentinum, post-caudectomy suppurative myelitis, fibrinosuppurative meningoencephalitis, polioencephalomalacia, rabies (2 cases or 3.4 percent each) were occasionally diagnosed. Spinal cord demyelinization, encephalic white matter edema, focal symmetrical encephalomalacia, hydranencephalia, cerebellar hypoplasia, poisoning by organophosphate, poisoning by Solanum pseudocapsicum, fibrinosuppurative myelitis, and presumptive closantel toxicity (1 case or 1.7 percent each) were rarely seen.(AU)

Meningoencefalite por Listeria monocytogenes em ovinos / Meningoencephalitis in sheep caused by Listeria monocytogenes

São descritos sete casos de doença neurológica em ovinos por Listeria monocytogenes no Rio Grande do Sul e Paraná entre 2000 e 2007. Foram afetados ovinos com idades entre 12-24 meses. Os casos ocorreram no verão e início da primavera e os índices gerais de morbidade e letalidade foram de 3,15% e 100%, respectivamente. Quando essa informação estava disponível, nenhum dos ovinos afetados era alimentado com silagem. Em três propriedades havia contato próximo dos ovinos afetados com outras espécies. A evolução do quadro clínico foi de 12 horas a três dias e os sinais clínicos foram caracterizados por decúbito (7/7), desvio da cabeça (4/7), incoordenação (3/7), depressão (3/7), andar em círculos (2/7), cegueira unilateral, emagrecimento progressivo, febre, midríase, movimentos de pedalagem, nistagmo lateral, opistótono, paralisia flácida dos membros pélvicos ou dos quatro membros, salivação excessiva e tremores (1/7 cada). Histologicamente observou-se encefalite com microabscessos, predominantemente unilateral com variáveis graus de gliose e alterações degenerativas como esferóides axonais e infiltração de células Gitter. As lesões se estendiam desde a medula oblonga até o mesencéfalo. Antígenos de Listeria monocytogenes foram detectados por imuno-histoquímica em seções de tronco encefálico de todos os ovinos afetados. O diagnóstico foi realizado com base nos achados epidemiológicos e clinico-patológicos, e confirmado pela imuno-histoquímica (IHQ) utilizando anticorpo policlonal anti-L. monocytogenes.(AU)

Seven cases of neurological disease in sheep caused by Listeria monocytogenes in Rio Grande do Sul and Paraná state, southern Brazil are described. The cases occurred between 2000 and 2007 and 12-24-month-old sheep were affected. Overall morbidity and lethality rates were 3.15% and 100%, respectively. Cases occurred in the summer and early spring. When this information was available, affected sheep had not been fed with silage. In three farms there were close contact among affected sheep and other species. Clinical signs were characterized by recumbency (7/7), head tilt (4/7), incoordination (3/7), depression (3/7), circling (2/7), unilateral blindness, wasting, fever, midriasis, paddling, opisthotonus, hind or hind and fore limb paralysis, drooling, and muscle tremors (1/7 each). Clinical evolution varied from 12 hours to three days. Histological findings consisted of predominantly unilateral, microabscedative encephalitis with variable degrees of gliosis and degenerative lesions characterized by axonal spheroids and infiltration by Gitter cells. These lesions were observed extending from medulla oblongata to mesencephalon. Listeria monocytogenes antigen was showed by imunohistochemistry in routinely processed sections of brainstem from all seven affected sheep. The diagnostic was based on epidemiological, clinical, and pathological findings and confirmed by immunohistochemistry (IHQ) using polyclonal anti-L. monocytogenes antibody.(AU)