Resultado da pesquisa (7)

Termo utilizado na pesquisa keratin

#1 - Detection of occult metastases of mammary carcinomas in lymph nodes of dogs by immunohistochemistry combined with histochemistry techniques

Abstract in English:

Lymph node status is considered an important clinical prognostic factor in canine mammary carcinomas and women’s breast neoplasms. However, occult isolated tumor cells (ITCs) can be missed during hematoxylin and eosin (HE) analyses. Immunohistochemistry (IHC) for cytokeratin can be used to detect carcinomatous occult ITCs in mammary drainage lymph nodes. However, brown pigments, such as hemosiderin and ceroid in lymph nodes, may hinder the search for occult metastases by IHC utilizing DAB (3,3′-diaminobenzidine) as the chromogen. The aim of this study was to identify ITCs in canine lymph nodes of cases in which it was not detectable by routine HE evaluation through IHC for cytokeratin (AE1/AE3) combined with histochemistry techniques, such as Perls’ Prussian blue and periodic acid-Schiff (PAS), to improve the detection of occult metastases when hemosiderin and ceroid were present in these lymph nodes. For this, 25 tubulopapillary mammary carcinomas with their respective submitted 29 regional lymph nodes, previously given as free of tumor cells by HE analyses, were selected. Mammary tumors were graduated, and vascular invasion was investigated in these tumors. The submitted lymph nodes were reevaluated in HE, looking for occult metastases. IHC for cytokeratin (AE1/AE3) was used to detect occult metastases in mammary lymph nodes. Subsequently, a combined technique of IHC with Perl’s Prussian blue (for hemosiderin) or PAS (for ceroid) was performed to optimize the detection of ITCs by IHC, distinguishing them from pigments. Occult metastases were classified by their microanatomical location in subcapsular, cortical and medullary. Hemosiderin and ceroid were searched in lymph nodes and quantified as low, moderate, or high. The amount of pigments with a percentage of ITCs was also compared. Isolated tumor cells were found in 24.1% (7/29) of mammary lymph nodes. These ITCs were located mainly in subcapsular sinuses (4/7; 57.1%), followed by cortical (2/7; 28.5%) and medullary sinuses (1/7; 14.3%). There were concomitant lymph nodes with ITCs in 33.4% (2/6) of cases with vascular invasion. Hemosiderin and ceroid were present in about 90% of the 29 lymph nodes analyzed. In 42.8% (3/7) of lymph nodes with ITCs, hemosiderin and/or ceroid were in the same location as ITCs. It was found that lymph nodes in which ITCs were detected also present high amounts of hemosiderin (3/7; 42.9%) and low amounts of ceroid (5/7; 71.4%). In this study, IHC for cytokeratin (AE1/AE3) was an efficient method to detect occult tumor cells. IHC combined with Perls’ Prussian blue or with PAS proved to be a helpful way to investigate the presence of occult metastases in the lymph nodes of mammary canine tumors. It allowed distinguishing hemosiderin and ceroid, respectively, from ITCs in the same slide of IHC (immunostained by DAB), favoring a more accurate analysis by pathologists, which can be useful for the oncological staging of these patients.

Abstract in Portuguese:

O status nodal é considerado um importante fator prognóstico clínico em cães com carcinomas mamários e em mulheres com neoplasmas mamários. No entanto, durante a análise histopatológica convencional (coloração de hematoxilina e eosina - HE), células neoplásicas podem permanecer ocultas no linfonodo. Imuno-histoquímica (IHQ) para citoqueratina pode ser utilizada para detectar células carcinomatosas isoladas ocultas em linfonodos de drenagem mamária. Entretanto, a presença de pigmentos marrons, como a hemossiderina e o ceroide em linfonodos, pode dificultar a procura por metástases ocultas durante a análise por IHQ utilizando o DAB (3,3′-diaminobenzidina) como cromógeno. O objetivo deste estudo foi identificar células tumorais isoladas (CTIs), não detectadas pela avaliação de rotina (HE), em linfonodos de cães, através de IHQ para citoqueratina (AE1/AE3) combinada com técnicas histoquímicas, como azul da Prússia e ácido periódico Schiff (PAS), para otimizar a detecção de metástases ocultas, quando os pigmentos hemossiderina e ceroide estavam presentes nos linfonodos. Para esta finalidade, 25 carcinomas mamários túbulo-papilares com seus respectivos 29 linfonodos regionais remetidos, previamente diagnosticados como livres de células neoplásicas pelo HE foram selecionados. Os tumores mamários foram graduados e a presença de invasão vascular foi investigada nestes tumores. Os linfonodos submetidos foram reavaliados histologicamente no HE, à procura de metástases ocultas. IHQ para citoqueratina (AE1/A3) foi utilizada para detectar metástases ocultas nos linfonodos mamários. Subsequentemente, técnicas combinadas de IHQ com azul da Prússia (para hemossiderina) ou PAS (para ceroide) foram realizadas para otimizar a detecção de CTIs através da IHQ, distinguindo-as dos pigmentos. As metástases ocultas foram classificadas pela sua região microanatômica nodal em subcapsular, cortical e medular. Hemossiderina e ceroide foram identificados no linfonodo e classificados de acordo com sua quantidade em baixa, moderada e alta. Também foram comparadas a quantidade de pigmentos com a porcentagem de CTIs. Foram encontradas CTIs em 24,1% (7/29) dos linfonodos mamários. Estas CTIs estavam localizadas principalmente em seios subcapsulares (4/7; 57,1%), seguido pela cortical (2/7; 28,5%) e seios medulares (1/7; 14,3%). Em 33,4% (2/6) dos casos com invasão vascular havia, concomitantemente, linfonodos de drenagem com CTIs. Hemossiderina e ceroide estavam presentes em cerca de 90% dos 29 linfonodos analisados. Em 42,8% (3/7) dos linfonodos com CTIs, hemossiderina e/ou ceroide estavam na mesma localização das CTIs. Os linfonodos que apresentaram CTIs também apresentavam grande quantidade de hemossiderina (3/7; 42,9%) e pequena quantidade de ceroide (5/7; 71,4%). Neste estudo, IHQ para citoqueratina (AE1/AE3) foi um método eficiente para detecção de células tumorais ocultas. A técnica combinada de IHQ com azul da Prússia ou com o ácido periódico de Schiff (PAS) mostrou ser uma maneira útil de investigar a presença de metástases ocultas em linfonodos de cães com tumores mamários caninos, distinguindo a hemossiderina e o ceroide, respectivamente, de CTIs na mesma lâmina de IHQ (imunomarcadas por DAB), favorecendo uma análise mais acurada pelos patologistas, o que pode ser útil no estadiamento oncológico destes pacientes.


#2 - Malignant epithelioid mesothelioma in senile Red Sindhi cows from Brazil

Abstract in English:

Mesotheliomas in cattle are often described as isolated case reports, and investigations of multiple cases within the same bovine herd are lacking. A series of cases of malignant epithelial mesothelioma, tubulopapilary type, is described in five 15 to 21-year-old Red Sindhi cows from the same herd. Clinical signs included three to eight months of progressive emaciation, dehydration, subcutaneous edema of the lower extremities, and abdominal distension. Grossly, severe subcutaneous edema and hydroperitoneum were noted. Multiple organs’ parietal and visceral serosal surfaces had multifocal to coalescing yellow, firm, sessile nodules ranging from 0.1 to 29.0cm. Similar free nodules floated in the peritoneal fluid. Histologically, the masses comprised a layer of cubic to columnar neoplastic cells forming papillary or cystic proliferation supported by a dense fibrovascular stroma. Neoplastic cells had strong and diffuse cytoplasmic immunolabeling for pan-cytokeratin but were negative for cytokeratin 7 and vimentin. Ultrastructurally, neoplastic cells had delicate microvilli and tight and anchoring junctions. Within the cytoplasm, a moderate amount of loose aggregate of intermediary filament with small mitochondria was observed. Epidemiological investigation evidenced endogamy in this herd. Asbestos exposure was not detected. The diagnosis was based on clinical, gross, histological, and immunohistochemical findings and confirmed by transmission electron microscopy features. A definitive underlying etiology remains unknown.

Abstract in Portuguese:

Mesotelioma em bovinos são frequentemente relatados como casos isolados, descrições de múltiplos casos no mesmo rebanho bovino não foram encontrados. Descreve-se uma série de casos de mesotelioma epitelial maligno, tipo tubulopapilar, em cinco vacas Red Sindi de 15 a 21 anos de idade do mesmo rebanho. Os sinais clínicos incluíram emagrecimento progressivo, desidratação, edema subcutâneo das extremidades dos membros e distensão abdominal em um curso clínico que variou de três a oito meses. Macroscopicamente, observou-se edema subcutâneo acentuado e hidroperitônio. Nas serosas parietais e viscerais de múltiplos órgãos haviam nódulos multifocais a coalescentes amarelo-claros, firmes e sésseis que variavam de 0,1 a 29,0 centímetros de diâmetro. Nódulos livres semelhantes também flutuavam no líquido peritoneal. Histologicamente, as massas eram compostas por uma camada de células cúbicas a colunares formando proliferação papilar ou cística sustentada por estroma fibrovascular denso. As células neoplásicas apresentavam imunomarcação citoplasmática forte e difusa para pan-citoqueratina, mas eram negativas para citoqueratina 7 e vimentina. Ultraestruturalmente, as células neoplásicas apresentavam delicadas microvilosidades e junções comunicantes e de ancoragem. No citoplasma observou-se moderada quantidade de agregados de filamentos intermediários soltos e pequenas mitocôndrias. A investigação epidemiológica revelou que não houve inserção de bovinos de outros rebanhos por mais de 30 anos e evidenciou endogamia. Não foram encontradas possíveis fontes de amianto para os bovinos deste rebanho. O diagnóstico de mesotelioma foi baseado em características clínicas, macroscópicas, histológicas, imuno-histoquímicas e confirmado pelos achados de microscopia eletrônica. A etiologia permanece desconhecida.


#3 - Isolation, cultivation and immunofluorescence characterization of lamellar keratinocytes from equine hoof by using explants

Abstract in English:

The importance of the hoof to the horse health is clear, and the current knowledge regarding the cellular aspects of hoof keratinocytes is poor. Studies on equine keratinocyte culture are scarce. Developing keratinocyte cultures in vitro is a condition for studies on molecular biology, cell growth and differentiation. Some methods have already been established, such as those for skin keratinocyte culture. However, few methodologies are found for lamellar keratinocytes. The objective of this study was to standardize the equine hoof keratinocyte isolation and cultivation, and then characterize the cell immunophenotype. For this, the primary culture method used was through explants obtained from three regions of the equine hoof (medial dorsal, dorsal, and lateral dorsal). After the cell isolation and cultivation, the cell culture and its explants were stained with anti-pan cytokeratin (pan-CK) (AE1/AE3), vimentin (V9), p63 (4A4), and Ki-67 (MIB-1) antibodies. Cells were grown to third passage, were positive for pan-CK, p63 and Ki-67, and few cells had vimentin positive expression. As for the explants, the epidermal laminae were not stained for vimentin or Ki-67. However, some cells presented positive pan-CK and p63 expression. This study demonstrated the viability of lamellar explants of equine hooves as a form of isolating keratinocytes in primary cultures, as well as characterized the proliferation ability of such keratinocytes in monolayers.

Abstract in Portuguese:

É notória a importância do casco na saúde dos equinos, mas o conhecimento em nível celular é pouco entendido. Estudos envolvendo o cultivo de queratinócitos equinos são escassos. Sabe-se que o desenvolvimento de cultivos de queratinócitos in vitro é uma condição para estudos sobre a biologia molecular, crescimento e diferenciação celular. Alguns métodos já estão estabelecidos, como para cultivo de queratinócitos de pele, mas poucas metodologias são encontradas para queratinócitos lamelares. O objetivo desse estudo foi padronizar o cultivo de queratinócitos provenientes de casco equino visando futuramente associar ao estudo da medicina regenerativa para assim estabelecer um modelo experimental in vitro e indicar o uso criterioso de terapias regenerativas para a laminite equina. Desta forma, o cultivo em monocamada e a caracterização de queratinócitos lamelares foram realizados. Para isso, o método de cultura primária utilizado foi através de explantes obtidos de três regiões do casco (dorso-medial, dorsal e dorso-lateral). As células foram caracterizadas para os marcadores anti pan-cytokeratin (AE1/AE3), vimentin (V9), p63 (4A4) e Ki-67 (MIB-1) nos cultivos e nos explantes. As  células foram cultivadas até terceira passagem, tendo marcação positiva para pan-CK, p63 e Ki-67 e fraca marcação para vimentina. Já as lâminas epidermais não tiveram marcação de vimentin e Ki-67, porém marcaram acentuadamente para pan-CK e p63. Este estudo demonstrou a exiquibilidade do uso de explantes lamelares do casco de equinos, como forma de isolamento de queratinócitos em cultivos primários, bem como caracterizou a habilidade de proliferação desses queratinócitos em monocamada.


#4 - Standardization of a PCR multiplex for the detection of dermatophytes in dogs and cats fur and crusts, 38(9):1824-1828

Abstract in English:

ABSTRACT.- Leal C.A.S., Kim P.C.P., Almeida J.C., Melo R.P.B., Santos A.S., Lima D.C.V., Pinheiro Júnior J.W. & Mota R.A. 2018. [Standardization of a PCR multiplex for the detection of dermatophytes in dogs and cats fur and crusts.] Padronização de multiplex PCR para detecção de dermatófitos em pelos e crostas de cães e gatos. Pesquisa Veterinária Brasileira 38(9):1824-1828. Laboratório de Doenças Infecciosas dos Animais Domésticos, Departamento de Medicina Veterinária, Universidade Federal Rural de Pernambuco, Av. Dom Manoel de Medeiros s/n, Dois Irmãos, Recife, PE 52171-900, Brazil. E-mail: c_adrianosl@hotmail.com The aim of this study was to standardize a multiplex PCR (mPCR) reaction to detect Microsporum canis, Microsporum gypseum and the Trichophyton mentagrophytes complex in dog and cat fur and/or crusts. 250 fur and/or crusts samples from dogs and cats were analyzed by direct examination and culture, DNA from them was extracted for mPCR. Primers were designed and the DNA extracted from colonies of M. canis (URM 6273), M. gypseum (URM 6921) and T. mentagrophytes (URM 6211) from the Collection of Cultures - URM Micoteca - Department of Mycology, Biological Sciences Center of the Federal University of Pernambuco (CCB / UFPE). As negative controls, sterile distilled water and DNA extracted from Alternaria sp., were used to verify the specificity of the primers. Of the total samples analyzed, 15 (6%) were identified in culture as dermatophytes, and of these, 10 were M. canis, three M. gypseum and two T. mentagrophytes (complex). Of these 15 positive samples, 11 (73.3%) were detected by mPCR. Besides these, six others, negative in culture, were identified as M. gypseum. There was good agreement between culture results and mPCR (Kappa: 0.66). The protocol standardized in this study can be used as a screening method, because it has a sensitivity greater than that of the culture, used in parallel to the routine exams, allowing a diagnosis in a shorter time.

Abstract in Portuguese:

RESUMO.- Leal C.A.S., Kim P.C.P., Almeida J.C., Melo R.P.B., Santos A.S., Lima D.C.V., Pinheiro Júnior J.W. & Mota R.A. 2018. [Standardization of a PCR multiplex for the detection of dermatophytes in dogs and cats fur and crusts.] Padronização de multiplex PCR para detecção de dermatófitos em pelos e crostas de cães e gatos. Pesquisa Veterinária Brasileira 38(9):1824-1828. Laboratório de Doenças Infecciosas dos Animais Domésticos, Departamento de Medicina Veterinária, Universidade Federal Rural de Pernambuco, Av. Dom Manoel de Medeiros s/n, Dois Irmãos, Recife, PE 52171-900, Brazil. E-mail: c_adrianosl@hotmail.com Objetivou-se padronizar uma reação do tipo multiplex PCR (mPCR) para detectar Microsporum canis, Microsporum gypseum e o complexo Trichophyton mentagrophytes em amostras de pelos e/ou crostas de cães e gatos. 250 amostras de pelos e/ou crostas de cães e gatos foram analisadas por meio de exame direto e cultura, o DNA das mesmas foi extraído para mPCR. Primers foram desenhados e como controle positivo da reação utilizou-se o DNA extraído de colônias de M. canis (URM 6273), M. gypseum (URM 6921) e T. mentagrophytes (URM 6211), provenientes da Coleção de Culturas (Micoteca URM), Departamento de Micologia, Centro de Ciências Biológicas da Universidade Federal de Pernambuco (CCB/UFPE). Como controles negativos de reação, utilizou-se água destilada esterilizada e DNA extraído de Alternaria sp. para verificar a especificidade dos primers. Do total de amostras analisadas, 15 (6%) foram identificadas, em cultura, como dermatófitos, e destas, 10 foram M. canis, três M. gypseum e dois T. mentagrophytes (complexo). Destas 15 amostras positivas, 11 (73,3%) foram detectadas por meio da mPCR. Além destas, seis outras, negativas em cultura, foram identificadas como M. gypseum. Verificou-se uma boa concordância entre os resultados da cultura e mPCR (Kappa: 0,66). O protocolo padronizado neste estudo pode ser utilizado como um método de triagem, por apresentar uma sensibilidade maior que a da cultura, usado paralelamente aos exames de rotina, permitindo um diagnóstico em menor tempo.


#5 - Transitional cell carcinoma of urinary bladder with metastasis in lumbar vertebrae and spinal cord compression in an ocelot (Leopardus pardalis), 35(1):75-79

Abstract in English:

ABSTRACT.- Nakagaki K.Y.R., Lima P.A., Utiumi K.U., Pires M.A.M., Zanatta R., Boabaid F.M., Colodel E.M. & Raymundo D.L. 2015. Transitional cell carcinoma of urinary bladder with metastasis in lumbar vertebrae and spinal cord compression in an ocelot (Leopardus pardalis. Pesquisa Veterinária Brasileira 35(1):75-79. Setor de Patologia Veterinária, Departamento de Medicina Veterinária, Universidade Federal de Lavras, Cx. Postal 3037, Lavras, MG 37200-000, Brazil. E-mail: djeison.raymundo@dmv.ufla.br This paper reports a case of nonpapillary and infiltrative transitional cell carcinoma (TCC) of the urinary bladder with metastasis of lumbar vertebrae and spinal cord compression in an adult female ocelot (Leopardus pardalis), from the Mato Grosso state, Brazil. The ocelot had pelvic limb paralysis and skin ulcers in the posterior region of the body and was submitted to euthanasia procedure. At necropsy was observed a multilobulated and irregular shaped, yellowish to white nodule in the urinary bladder. The nodule had a soft consistency and arised from the mucosa of the urinary bladder extending throughout the muscular layers and the serosa. Nodules of similar appearance infiltrating the vertebral column the at L6 and L7 vertebrae with corresponding spinal canal invasion were also observed. The histological evaluation showed epithelial neoplastic proliferation in the urinary bladder with characteristics of nonpapillary and infiltrative TCC, with positive immunohistochemical staining for pancytokeratin, and strong immunostaining for cytokeratin of low molecular weight, and weak or absent labeling for high molecular weight cytokeratin. This is the first report of TCC of urinary bladder in ocelot in Brazil.

Abstract in Portuguese:

RESUMO.- Nakagaki K.Y.R., Lima P.A., Utiumi K.U., Pires M.A.M., Zanatta R., Boabaid F.M., Colodel E.M. & Raymundo D.L. 2015. Transitional cell carcinoma of urinary bladder with metastasis in lumbar vertebrae and spinal cord compression in an ocelot (Leopardus pardalis. [Carcinoma de células de transição de bexiga urinária com metástase em vértebras lombares e compressão de medula espinhal em uma jaguatirica (Leopardus pardalis).] Pesquisa Veterinária Brasileira 35(1):75-79. Setor de Patologia Veterinária, Departamento de Medicina Veterinária, Universidade Federal de Lavras, Cx. Postal 3037, Lavras, MG 37200-000, Brazil. E-mail: djeison.raymundo@dmv.ufla.br O presente trabalho relata um caso de carcinoma de células de transição (TCC) da bexiga urinária com metástase em vértebras lombares e compressão da medula espinhal em uma jaguatirica fêmea adulta (Leopardus pardalis), no estado do Mato Grosso. A jaguatirica manifestava paralisia de membros pélvicos e úlceras de decúbito na região posterior do corpo e foi submetida a eutanásia. Na necropsia observou-se um nódulo multilobulado e irregular, brancoamarelado na bexiga urinária, de consistência macia com origem na mucosa vesical e que se estendia às camadas musculares e à serosa. Nódulos de aspecto semelhante infiltrando as vértebras L6 e L7 e invasão do canal vertebral correspondente. No exame histológico foi observada proliferação neoplásica na bexiga urinária com com características de TCC não papilar e infiltrativo, com marcação imuno-histoquímica positiva para pancitoqueratina, forte marcação para citoqueratina de baixo peso molecular e fraca ou inexistente para citoqueratina de alto peso molecular. Este é o primeiro relato de TCC em bexiga urinária de jaguatirica no Brasil.


#6 - Patogênese das lesões associadas à intoxicação por Ramaria flavo-brunnescens em bovinos, p.533-544

Abstract in English:

ABSTRACT.- Trost M.E., Kommers G.D., Barros C.S.L & Schild A.L. 2009. [Patogenesis of lesions associated with poisoning by Ramaria flavo-brunnescens in cattle.] Patogênese das lesões associadas à intoxicação por Ramaria flavo-brunnescens em bovinos. Pesquisa Veterinária Brasileira 29(7):533-544. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: glaukommers@yahoo.com The pathogenesis of the lesions of Ramaria flavo-brunnescens poisoning in cattle was studied throughout the retrospective evaluation of selected tissues from nine spontaneous and four experimental cases of the disease. The pathogenesis of lesions observed in the tongue, esophagus, hoof, and tail was investigated analyzing microscopic lesions, histochemical and histochemical-ultrastructural changes. Histochemical techniques utilized were Masson’s Trichrome and Selective Oxidation of Keratin (SOK). The histochemical-ultrastructural study was acomplished throughout the Swift method under transmission electron microscopy. Hair shafts of the tip of the tail were analyzed under polarized light. Lesions of varying degrees of severity were observed. All changes observed in the keratinized structures studied, mostly in the hard keratin, showed defective keratinization. The morphologic study and the results obtained with SOK and Swift techniques showed that the defective keratinization results of low amounts of sulphur containing amino acids (cystine) in hard keratin structures. This is probably the main pathogenetic mechanism of the lesions observed in R. flavo brunnescens poisoning in cattle.

Abstract in Portuguese:

ABSTRACT.- Trost M.E., Kommers G.D., Barros C.S.L & Schild A.L. 2009. [Patogenesis of lesions associated with poisoning by Ramaria flavo-brunnescens in cattle.] Patogênese das lesões associadas à intoxicação por Ramaria flavo-brunnescens em bovinos. Pesquisa Veterinária Brasileira 29(7):533-544. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: glaukommers@yahoo.com The pathogenesis of the lesions of Ramaria flavo-brunnescens poisoning in cattle was studied throughout the retrospective evaluation of selected tissues from nine spontaneous and four experimental cases of the disease. The pathogenesis of lesions observed in the tongue, esophagus, hoof, and tail was investigated analyzing microscopic lesions, histochemical and histochemical-ultrastructural changes. Histochemical techniques utilized were Masson’s Trichrome and Selective Oxidation of Keratin (SOK). The histochemical-ultrastructural study was acomplished throughout the Swift method under transmission electron microscopy. Hair shafts of the tip of the tail were analyzed under polarized light. Lesions of varying degrees of severity were observed. All changes observed in the keratinized structures studied, mostly in the hard keratin, showed defective keratinization. The morphologic study and the results obtained with SOK and Swift techniques showed that the defective keratinization results of low amounts of sulphur containing amino acids (cystine) in hard keratin structures. This is probably the main pathogenetic mechanism of the lesions observed in R. flavo brunnescens poisoning in cattle.


#7 - Intoxicação por Ramaria flavo-brunnescens (Clavariaceae) em bovinos

Abstract in English:

ABSTRACT.- Barros R.R., Irigoyen L.F., Kommers G.D., Rech R.R., Fighera R.A. & Barros C.S.L. 2006. [Poisoning by Ramaria flavo-brunnescens (Clavariaceae) in cattle.] Intoxicação por Ramaria flavo-brunnescens (Clavariaceae) em bovinos. Pesquisa Veterinária Brasileira 26(2):87-96. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br Two oubreaks of poisoning by the mushroom Ramaria flavo-brunnescens are reported in cattle from two farms located in the municipalities of Santa Maria and São Gabriel, state of Rio Grande do Sul, during April-May 2005. Out of a total of 180 yearling calves that had access to a pasture with eucalyptus woods, 19 were affected and 10 died. The clinical courses were 8-15 days and clinical signs included depression, weight loss, dehydration, drooling, loosening and loss of the long hairs of the tip of the tail, smoothening of the dorsal surface of the tongue with occasional ulceration, loosening of the corneal encasement of horns, hard and ball-shaped feces covered with a film of mucous, hypopion, hyphema and corneal opacity. Two calves had leucocytosis due to mild regenerative left shift. Nine calves were necropsied. Necropsy findings confirmed the clinical observation and additionaly included fibrinonecrotic esophagitis, mainly in the distal third of the esophageal mucosa. Histopathological changes in the skin of the tail included orthokeratotic hyperkeratosis; hair folicles with irregular contours, thickening of the tricolemmal keratin layer with occasional formation of keratin plugs, and degeneration and necrosis of the outer root sheath. At the laminar region of the hooves, there was hyperplasia of the top of epidermal laminae with irregular keratinization and retention of nuclei; several epidermal laminae were shortened and fused. There was hemorrhage, fibrin and neutrophilic infiltrate in the dermal laminae. In the mucosa of the tongue there was thinning of the covering epithelium, atrophy and loss of filiform papillae, multifocal areas of dyskeratosis, and spongiosis of the basal cell layer. In some parts the epithelium was lost and the surface consisted of granulation tissue and mixed inflammatory cell infiltrate. The esophageal mucosae of six calves had varying degree of epithelial necrosis and inflammation. The loss of the covering epithelium revealed an underneath area of granulation tissue with heavy inflammatory infiltrate composed predominantly of neutrophils and macrophages. In six calves there were focal symmetric bilateral areas of malacia observed at the level of obex in the medulla oblongata and affecting the white matter and parts of the dorsal nucleus of the vagus and of the hypoglossal nucleus. The epidemiology, clinical signs, pathology, and pathogenesis of poisoning by R. flavo-brunnescens in cattle are discussed.

Abstract in Portuguese:

ABSTRACT.- Barros R.R., Irigoyen L.F., Kommers G.D., Rech R.R., Fighera R.A. & Barros C.S.L. 2006. [Poisoning by Ramaria flavo-brunnescens (Clavariaceae) in cattle.] Intoxicação por Ramaria flavo-brunnescens (Clavariaceae) em bovinos. Pesquisa Veterinária Brasileira 26(2):87-96. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br Two oubreaks of poisoning by the mushroom Ramaria flavo-brunnescens are reported in cattle from two farms located in the municipalities of Santa Maria and São Gabriel, state of Rio Grande do Sul, during April-May 2005. Out of a total of 180 yearling calves that had access to a pasture with eucalyptus woods, 19 were affected and 10 died. The clinical courses were 8-15 days and clinical signs included depression, weight loss, dehydration, drooling, loosening and loss of the long hairs of the tip of the tail, smoothening of the dorsal surface of the tongue with occasional ulceration, loosening of the corneal encasement of horns, hard and ball-shaped feces covered with a film of mucous, hypopion, hyphema and corneal opacity. Two calves had leucocytosis due to mild regenerative left shift. Nine calves were necropsied. Necropsy findings confirmed the clinical observation and additionaly included fibrinonecrotic esophagitis, mainly in the distal third of the esophageal mucosa. Histopathological changes in the skin of the tail included orthokeratotic hyperkeratosis; hair folicles with irregular contours, thickening of the tricolemmal keratin layer with occasional formation of keratin plugs, and degeneration and necrosis of the outer root sheath. At the laminar region of the hooves, there was hyperplasia of the top of epidermal laminae with irregular keratinization and retention of nuclei; several epidermal laminae were shortened and fused. There was hemorrhage, fibrin and neutrophilic infiltrate in the dermal laminae. In the mucosa of the tongue there was thinning of the covering epithelium, atrophy and loss of filiform papillae, multifocal areas of dyskeratosis, and spongiosis of the basal cell layer. In some parts the epithelium was lost and the surface consisted of granulation tissue and mixed inflammatory cell infiltrate. The esophageal mucosae of six calves had varying degree of epithelial necrosis and inflammation. The loss of the covering epithelium revealed an underneath area of granulation tissue with heavy inflammatory infiltrate composed predominantly of neutrophils and macrophages. In six calves there were focal symmetric bilateral areas of malacia observed at the level of obex in the medulla oblongata and affecting the white matter and parts of the dorsal nucleus of the vagus and of the hypoglossal nucleus. The epidemiology, clinical signs, pathology, and pathogenesis of poisoning by R. flavo-brunnescens in cattle are discussed.


Colégio Brasileiro de Patologia Animal SciELO Brasil CAPES CNPQ UFRRJ CFMV