Cardiac hypertrophy associated with Corynebacterium spp. in Didelphis albiventris cubs

The purpose of this manuscript is to describe the clinical-pathological aspects of cardiac hypertrophy related to the presence of Corynebacterium spp. in three Didelphis albiventris cubs. In necropsy, macroscopically, in the heart, cardiomegaly, concentric hypertrophy of the ventricles and the ventricular septum were observed, with consequent reduction of the chamber. Microscopically, the primary lesions found in the heart were cardiomyocyte hypertrophy and necrosis, myocytolysis, and the presence of myriad basophilic bacteria. Liver fragments and endocardial swabs were sent for bacterial culture, in which pleomorphic Gram-positive rods grew, forming small and hemolytic colonies. Chemical tests demonstrated characteristics compatible with Corynebacterium spp. Thus, this report represents the first description of cardiac hypertrophy associated with Corynebacterium spp. in white-eared opossums cubs, representing an essential contribution to studying diseases in wild animals.(AU)

Urethral obstruction due to seminal vesiculitis in a sheep: case report / Obstrução uretral por vesiculite seminal em ovino: relato de caso

We report a case of urethral obstruction due to seminal vesiculitis in a Dorper sheep, with symptoms of anuria, rectal prolapse, orchitis/epididymitis, and uroperitoneum and biochemical tests indicating severe azotemia. The animal died due to advanced azotemia, and necropsy revealed kidneys with cortical and medullary necrosis, pyelonephritis of renal calyces, hydronephrosis, ruptured and necrotic bladder, and vesicular, bulbourethral, and ampoule accessory sex glands. There was prostate hyperplasia that revealed a large amount of pus in the cross section, which was also observed bilaterally in the epididymis and right testis. Morphotintorial and biochemical analyses of bacteria obtained from microbiological culture revealed Corynebacterium sp. and Escherichia coli. Infection, hyperplasia, and abscessation of accessory sex glands caused urethral compression, resulting in an obstructive condition, similar to urolithiasis, in addition to bacteremia. Hyperplastic seminal vesiculitis, although rare, must be included among the differential diagnoses of obstructive processes in the urinary tract of sheep.

Relata-se um caso de obstrução uretral decorrente de vesiculite seminal em carneiro da raça Dorper, com quadro de anúria, prolapso retal, orquite/epididimite e uroperitôneo, com exames bioquímicos indicativos de severa azotemia. Devido ao quadro avançado de azotemia, o animal faleceu e, na necropsia, foi observado:: rins com necrose de cortical e medular, pielonefrite dos cálices renais e hidronefrose, bexiga rompida e necrosada, assim como glândulas sexuais acessórias vesiculares, bulbouretrais e ampola. Havia hiperplasia de próstata que, ao corte transversal, revelou grande quantidade de pus, que também foi observado bilateralmente no epidídimo e no testículo direito. As análises morfotintoriais e bioquímicas das bactérias obtidas a partir do cultivo microbiológico foram compatíveis com Corynebacterium sp. e Escherichia coli. A infecção, a hiperplasia e a abscedação das glândulas sexuais acessória, causaram compressão uretral, levando a um quadro obstrutivo, semelhante à urolitíase, somado à bacteremia. A vesiculite seminal hiperplásica, apesar de rara, deve ser incluída entre os diagnósticos diferenciais dos processos obstrutivos do trato urinário de carneiros.

Soroprevalência da infecção por Corynebacterium pseudotuberulosis em caprinos no Nordeste brasileiro utilizando técnica de imunoabsorção enzimática (ELISA-indireto) / Serological study on Corynebacterium pseudotuberculosis infection in goats in the Brazilian Northeast using enzyme-linked immunosorbent assay (ELISA-indirect)

A caprinocultura na região Nordeste do Brasil desempenha importante função socioeconômica e estratégica. A rusticidade desta atividade nesta região, aliada a sua rápida expansão em outros estados, tem gerado perdas na sua cadeia produtiva a nível regional e nacional, causadas por doenças infecciosas, destacando-se a Linfadenite Caseosa (LC), afecção amplamente difundida nos rebanhos caprinos, acarretando sérios prejuízos econômicos à atividade. Embora LC tenha sido detectada como um problema endêmico no nordeste brasileiro, uma análise abrangente e mais recente desta prevalência nos rebanhos caprinos brasileiros se faz necessária. O objetivo desse estudo foi determinar a frequência de anticorpos anti-Corynebacterium pseudotuberculosis em cinco dos nove estados que compõem a região Nordeste do Brasil. Foram processadas amostras de soro de 2571 caprinos provenientes de 218 propriedades rurais oriundas de cinco estados da região Nordeste do Brasil, coletadas entre os anos de 2010 a 2012. O diagnóstico da infecção por C. pseudotuberculosis foi realizado pela técnica de ELISA-indireto. Em 88,5% (193/218) das propriedades investigadas, pelo menos um caprino foi soropositivo para C. pseudotuberculosis, sugerindo que o agente se encontra disseminado nos rebanhos do Nordeste, com a maior prevalência encontrada no Rio Grande do Norte (94,5%) e a menor no estado de Sergipe (70,3%). Foram identificados 783 (30,4%; IC 95%=28,7-32,2%) caprinos soropositivos, com a maior prevalência entre animais encontrada no Piauí (41,4%) e a menor no estado de Sergipe (22,5%). De um total de 279 reprodutores avaliados, 106 (37,9%) resultaram soropositivos, destacando-se o Rio Grande do Norte, com 45,30%, e Piauí com 46,8% dos reprodutores positivos para LC. Das 1420 matrizes testadas, 599(42,1%) apresentaram sorologia positiva para C. pseudotuberculosis. Entre os estados esta distribuição também se manteve semelhante, destacando-se o Rio Grande do Norte, com 47,5% e Piauí com 59,5% das matrizes positivos para LC. Entre os 872 caprinos jovens avaliados, 78 (8,9%) foram soropositivos para LC, observando-se uma diferença estatística na frequência de sopositividade obtidas entre os adultos e os jovens (P<0,001). Reforça-se a necessidade do diagnóstico da enfermidade em rebanhos caprinos da região Nordeste para possível implementação de programas de controle da doença e medidas mais precisas no manejo da LC junto aos criadores de caprinos.(AU)

Goat farming in the Northeast region of Brazil plays an important socioeconomic and strategic role. The rusticity of this activity in this region, allied with its rapid expansion in other states, has caused losses in its production chain in regional and national levels, caused by infectious diseases, especially caseous lymphadenitis (CL), a widespread goat herds disease which has been causing serious economic loss to this activity. Although CL has been detected as an endemic problem in the Brazilian Northeast, a comprehensive and more recent analysis of this prevalence in Brazilian goats is necessary. The objective of this study was to determine the frequency of anti-Corynebacterium pseudotuberculosis antibodies in five of nine states of the northeast region of Brazil. Serum samples were collected from 2571 goats from 218 farms in five states in the Northeast region of Brazil, collected between 2010 and 2012. The diagnosis of C. pseudotuberculosis infection was made using the ELISA-indirect technique. In 88.5% (193/218) of the investigated properties, at least one goat was seropositive for C. pseudotuberculosis, suggesting that the agent is widespread in Northeast herds, with the highest prevalence found in Rio Grande do Norte (94.5%) and the lowest one in the state of Sergipe (70.3%). A total of 783 (30.45%; 95% CI = 28.71-32.26%) seropositive goats were found, and the highest prevalence among animals was found in Piauí (41.4%) and the lowest in the state of Sergipe (22.5%). Out of a total of 279 breeding herds, 106 (37.99%) were seropositive, standing out the Rio Grande do Norte, with a total of 45.30%, and Piauí 46.8% of positive breeding for CL. A total of the 1420 tested matrices, 599 (42.1%) presented positive serology for C. pseudotuberculosis. Among the States, this distribution also remained similar, standing out Rio Grande do Norte with 47.5%, and Piauí with 59.5% of positive matrices for CL. Among 872 young goats evaluated, 78 (8.9%) were seropositive for CL, observing a statistical difference in the frequency of soropositivity obtained between adults and young adults (P<0.001). The necessity to diagnose the disease in goat herds in the Northeast region is reinforced for the possible implementation of disease control programs and more precise measures to manage CL along with goat farmers.(AU)

Soroprevalência da infecção por Corynebacterium pseudotuberulosis em caprinos no Nordeste brasileiro utilizando técnica de imunoabsorção enzimática (ELISA-indireto) / Serological study on Corynebacterium pseudotuberculosis infection in goats in the Brazilian Northeast using enzyme-linked immunosorbent assay (ELISA-indirect)

A caprinocultura na região Nordeste do Brasil desempenha importante função socioeconômica e estratégica. A rusticidade desta atividade nesta região, aliada a sua rápida expansão em outros estados, tem gerado perdas na sua cadeia produtiva a nível regional e nacional, causadas por doenças infecciosas, destacando-se a Linfadenite Caseosa (LC), afecção amplamente difundida nos rebanhos caprinos, acarretando sérios prejuízos econômicos à atividade. Embora LC tenha sido detectada como um problema endêmico no nordeste brasileiro, uma análise abrangente e mais recente desta prevalência nos rebanhos caprinos brasileiros se faz necessária. O objetivo desse estudo foi determinar a frequência de anticorpos anti-Corynebacterium pseudotuberculosis em cinco dos nove estados que compõem a região Nordeste do Brasil. Foram processadas amostras de soro de 2571 caprinos provenientes de 218 propriedades rurais oriundas de cinco estados da região Nordeste do Brasil, coletadas entre os anos de 2010 a 2012. O diagnóstico da infecção por C. pseudotuberculosis foi realizado pela técnica de ELISA-indireto. Em 88,5% (193/218) das propriedades investigadas, pelo menos um caprino foi soropositivo para C. pseudotuberculosis, sugerindo que o agente se encontra disseminado nos rebanhos do Nordeste, com a maior prevalência encontrada no Rio Grande do Norte (94,5%) e a menor no estado de Sergipe (70,3%). Foram identificados 783 (30,4%; IC 95%=28,7-32,2%) caprinos soropositivos, com a maior prevalência entre animais encontrada no Piauí (41,4%) e a menor no estado de Sergipe (22,5%). De um total de 279 reprodutores avaliados, 106 (37,9%) resultaram soropositivos, destacando-se o Rio Grande do Norte, com 45,30%, e Piauí com 46,8% dos reprodutores positivos para LC. Das 1420 matrizes testadas, 599(42,1%) apresentaram sorologia positiva para C. pseudotuberculosis. Entre os estados esta distribuição também se manteve semelhante, destacando-se o Rio Grande do Norte...(AU)

Goat farming in the Northeast region of Brazil plays an important socioeconomic and strategic role. The rusticity of this activity in this region, allied with its rapid expansion in other states, has caused losses in its production chain in regional and national levels, caused by infectious diseases, especially caseous lymphadenitis (CL), a widespread goat herds disease which has been causing serious economic loss to this activity. Although CL has been detected as an endemic problem in the Brazilian Northeast, a comprehensive and more recent analysis of this prevalence in Brazilian goats is necessary. The objective of this study was to determine the frequency of anti-Corynebacterium pseudotuberculosis antibodies in five of nine states of the northeast region of Brazil. Serum samples were collected from 2571 goats from 218 farms in five states in the Northeast region of Brazil, collected between 2010 and 2012. The diagnosis of C. pseudotuberculosis infection was made using the ELISA-indirect technique. In 88.5% (193/218) of the investigated properties, at least one goat was seropositive for C. pseudotuberculosis, suggesting that the agent is widespread in Northeast herds, with the highest prevalence found in Rio Grande do Norte (94.5%) and the lowest one in the state of Sergipe (70.3%). A total of 783 (30.45%; 95% CI = 28.71-32.26%) seropositive goats were found, and the highest prevalence among animals was found in Piauí (41.4%) and the lowest in the state of Sergipe (22.5%). Out of a total of 279 breeding herds, 106 (37.99%) were seropositive, standing out the Rio Grande do Norte, with a total of 45.30%, and Piauí 46.8% of positive breeding for CL. A total of the 1420 tested matrices, 599 (42.1%) presented positive serology for C. pseudotuberculosis. Among the States, this distribution also remained similar, standing out Rio Grande do Norte with 47.5%, and Piauí with 59.5% of positive matrices for CL. Among 872 young goats... (AU)

Thoracic aortic aneurysm in a buck associated with caseous lymphadenitis / Aneurisma de aorta torácica associado à linfadenite caseosa em caprino reprodutor

This paper reports the clinical, bacteriological and pathological findings of a thoracic aortic aneurysm in a four-year-old Anglo-Nubian goat buck, related to a framework of visceral caseous lymphadenitis. General clinical examination showed heart rate of 75 beats per minute, respiratory rate of 20 movements per minute and ruminal movements of four movements per minute. Superficial lymph nodes were normal upon palpation. Rectal temperature was slightly high (40.5°C). Blood test showed an intense leukocytosis (54,000/µL), characterized by strong neutrophil shift to the left. At necropsy, a large blood clot was detected in the thoracic cavity. The thickening of the myocardium and dilatation of the aorta in the thoracic portion, presenting a saculiform format was also observed. A large number of abscesses were disseminated in the media and intima layers of aorta. The aorta lumen obstruction by arterial plaques consisting of inflammatory infiltrate, predominantly neutrophilic was also detected. Abscesses were found spread in turbinate, rumen, reticulum, kidneys, liver, spleen, testicles and aorta wall. The microbiological exam of exudate confirmed Corynebacterium pseudotuberculosis as the causal agent.(AU)

Este trabalho descreve os achados clínicos, bacteriológicos e patológicos de um aneurisma da aorta torácica em um reprodutor caprino da raça Anglo-Nubiana, de quatro anos de idade, relacionado a um caso de linfadenite caseosa visceral. Ao exame clínico geral observaram-se: frequência cardíaca de 75 batimentos por minuto, frequência respiratória de 20 movimentos por minuto e movimentos ruminais de quatro movimentos por minuto. Os linfonodos superficiais encontravam-se normais à palpação. A temperatura retal estava ligeiramente aumentada (40,5°C). No hemograma completo, observou-se leucocitose intensa, 54.000/µL, caracterizada por um forte desvio neutrofílico à direita. Nos achados de necropsia, observou-se, na cavidade torácica, presença de um grande coágulo de sangue. No coração, foi identificado espessamento do miocárdio. Uma dilatação na porção torácica da artéria aorta foi detectada, apresentando um aspecto saculiforme. Um grande número de abscessos estava presente nas camadas média e íntima da aorta. Observou-se, também, obstrução do lúmen da aorta por placas de infiltrado inflamatório, predominantemente neutrofílico. A disseminação de abscessos nos cornetos, rúmen, retículo, fígado, baço, rins, testículos e parede da aorta foi detectada. O exame microbiológico do exsudato confirmou o Corynebacterium pseudotuberculosis como o agente causal.(AU)

Isolation and identification of main mastitis pathogens in Mexico / Isolação e identificação dos micróbios patogênicos principais da mastite em México

The present work is a large epidemiological study aiming to detect the prevalence of subclinical mastitis and to investigate the major udder pathogens in Jalisco State, western Mexico. For this purpose, 2205 dairy cows, representing 33 Mexican dairy herds, were involved. Of 2205 cows, 752 mastitic animals were diagnosed and only 2,979 milk samples could be obtained for further investigation. All 2979 milk samples were subjected to California Mastitis Test (CMT) to differentiate clinical cases from subclinical ones where 1996 samples (67 %) reacted positively. Of these, 1087 samples (54.5%) came from cows suffering from clinical cases of mastitis. Bacteriological identification of the causative agents revealed the presence of a major group of pathogens including the Coagulase negative staphylococci (CNS), S.aureus, S.agalactiae, Corynebacterium spp. and Coliform bacteria which were detected in 464 (15.6%), 175 (5.9%), 200 (6.8%), 417 (14%) and 123 (4.1%) of the 2927 investigated quarters, 295 (15.4%), 118 (15.7%), 111 (14.8%), 227 (30.2%) and 109 (14.5%) of the 752 examined cows and in 33 (100%), 22 (66.7%), 19 (57.6%), 30 (90.1%) and 27 (81.8%) of the 33 herds involved, respectively. Other pathogens could be detected in the investigated milk samples such as S. dysgalactiae (0.4%), S.uberis (0.37%), Bacillus spp. (1%), Nocardia spp. (0.6%) und Candida spp. (0.1%). Meanwhile, others were present in a negligible ratio; including the Aerococcus viridans, and Enterococcus spp., Lactococcus lactis, S. bovis.(AU)

O trabalho atual é um estudo epidemiológico que objetiva detectar a predominância da mastite subclínica e investigar os micróbios patogênicos principais do úbere no México ocidental. Com esta finalidade, foram utilizadas 2205 vacas leiteiras, representando 33 rebanhos de leiteiras mexicanas. Além dessas 2205 vacas, 752 animais com mastite foram diagnosticados, considerando-se que somente 2979 amostras do leite poderiam ser obtidas para a posterior investigação. Todas as 2979 amostras do leite foram submetidas ao teste da mastite de Califórnia (CMT) para diferenciar casos clínicos dos subclínicos, visto que 1996 amostras (67%) reagiram positivamente. Além dessas, 1087 amostras (54.5%) vieram das vacas que sofrem de casos clínicos de mastite. A identificação bacteriológica dos agentes causais revelou a presença dos Staphylococcus negativos para coagulase (CNS), S. aureus, S. agalactiae, outros spp. Streptococcal, Corynebacterium spp., e as bactérias de coliformes foram detectadas em 464 (15.6%), 175 (5.9%), 200 (6.8%), 109 (3.9%), 417 (14%) e em 123 (4.1%) dos 2927 quartos investigados; em 295 (15.4%), 118 (15.7%), 111 (14.8%), 95 (12.6%), 227 (30.2%) e em 109 (14.5%) das 752 vacas examinadas e, finalmente, em 33 (100%), 22 (66.7%), 19 (57.6%), 30 (90.1%), 30 (90.1%) e em 27 (81.8%) dos 33 rebanhos envolvidos, respectivamente.(AU)

Yeast mastite outbreak in a Brazilian dairy herd / Surto de mastite causado por leveduras em um rebanho brasileiro

This study aimed to describe an outbreak of bovine mastitis caused by yeast in a dairy herd located in the state of Minas Gerais, Brazil. Microbiological analysis of milk samples (106) of the infected mammary quarters of lactating cows showed that Corynebacterium bovis (43.48%) and yeasts from the genus Candida (29.35%) were the main agents isolated in the herd. C. albicans(33.34%), C. catenulate (22.23%) and C. glabrata (18.52%) were the species most commonly isolated. The high prevalence of yeast mastitis was associated with lack of training formilkers, repetitive intramammary treatment and poor teat hygiene prior to the intramammary infusion. Appropriate management measures, specific treatment with antifungal drugs and removal of chronically infected animals were effective for the control of mastitis outbreak.(AU)

O objetivo deste estudo foi descrever um surto de mastite bovina causada por leveduras em um rebanho leiteiro localizado no Estado de Minas Gerais, Brasil. Análises microbiológicas de amostras de leite (106) dos quartos mamários infectados de vacas em lactação demonstraram que Corynebacterium bovis (43,48%) e leveduras do gênero Candida (29,35%) foram os principais agentes isolados no rebanho. C. albicans (33,34%), C. catenulata (22,23%) e C. glabrata (18,52%) foram as espécies mais comumente isoladas. A elevada prevalência da mastite por leveduras foi associada à falta de treinamento dos ordenhadores, ao tratamento intramamário repetitivo e a falhas na higienização de tetas antes da infusão intramamária. Medidas adequadas de manejo, tratamento específico com drogas antifúngicas e descarte de animais cronicamente infectados foram eficazes para o controle do surto.(AU)

A proposal of a diagnostic protocol for isolation of Corynebacterium ulcerans from cow's milk

Background: Literature about presence Corynebacterium ulcerans in milk samples from cows with mastitis is rare and in the literature there are only a few reports. In this study the isolation and identification of Corynebacterium ulcerans from mastitis in dairy cows were done. Also, optimization of diagnostic protocols to identify Corynebacterium ulcerans was performed. Materials, Methods & Results: The investigation was performed at the cattle farm that is characterized by closed housing system diary Holstein-Friesian cows during an outbreak of acute mastitis. Milk samples from 298 lactating cows were collected in sterile sampling tubes. Before the collection of quarter milk samples, the udder was thoroughly cleaned with soap and water and rubbed to dry. All collected milk samples were examined for mastitis using California mastitis test, which was carried out by the method first described by Schalm and Noorlander. Equal volumes (5 mL) of commercial CMT reagent and quarter milk were mixed and the changes in milk fluidity and viscosity were observed. Sample portions (0.1 mL each) were inoculated on 10% sheep blood agar, Endo agar and Sabouraud agar as well as on thioglycolate medium and nutrient broth. Primary plates were incubated for 3 days at 37ºC in aerobic conditions. Cultural, morphological and conventional biochemical testing was done. The survey was complemented by double CAMP and plasma coagulation tube test. All 14 isolates developed a synergistic haemolysis with Rhodococcus equi (ATCC 6939) and inverse CAMP phenomenon with Staphylococcus aureus and coagulated rabbit plasma. Final diagnosis was confirmed using API Coryne V 2.0 and software program by BioMerieux1, revealing an identity rate of 99.9%, accuracy rate T = 1, test count = 0. Discussion: The first fourteen isolates of Corynebacterium ulcerans have been identified in our country, on the basis of a diagnostic protocol that is proposed in this paper. In our experience double CAMP test, rabbit plasma coagulation, catalase, oxidase tests and selected biochemical parameters, are sufficient as a diagnostic minimum. In the diagnostics of bacterial agents in cow mastitis, the attention of a bacteriologist is mostly limited to most widespread agents of mastitis, the isolation of which is mandatory pursuant to national legislation (Staphylococcus aureus and Streptococcus agalactiae). A more important reason for "missing" Corynebacterium ulcerans in the diagnosis is its colonial morphology that could resemble organisms of the genus Staphylococcus. Complex and expensive diagnostic procedure that is not available to most laboratories is also responsible for the small number of reports of isolation C. ulcerans. Furthermore, in routine work C. ulcerans could be misidentified with Staphylococcus intermedius, because of cultural similarity, positive plasma coagulation tube test and absence of manitol fermentation of both species. This paper is a report on isolation and identification of Corynebacterium ulcerans from milk of cows with mastitis, as well as a suggestion of a diagnostic protocol available for routine work in most veterinary microbiology laboratory. Therefore we suggest as the diagnostic protocol double CAMP test to be used as a complementary method to rabbit plasma coagulation tube test.

Linfadenite caseosa em ovinos deslanados abatidos em um frigorífico da Paraíba1 / Caseous lymphadenitis in slaughtered hair sheep in northeastern Brazil

Este trabalho teve como objetivo determinar a prevalência e distribuição de lesões da linfadenite caseosa em ovinos deslanados abatidos no município de Mulungu, Paraíba. Dos 1466 ovinos abatidos, 236 (15,9%) apresentaram lesões macroscópicas semelhantes à linfadenite caseosa. A prevalência foi maior em fêmeas, 17.9% (135/754) que em machos, 13,8% (101/732). As principais lesões estavam localizadas nos linfonodos pré-escapulares em 36,3% (97/268) dos ovinos, nos parotídeos em 22,4% (60/268) e no pré-crural em 20,9% (56/268). Somente 70 (26,1%) de um total de 268 lesões foram detectadas no exame ante mortem. Foram encontradas lesões em todos os lotes provenientes de diversos municípios da Paraíba, Pernambuco e Bahia. Das 51 amostras em que foi feito o cultivo bacteriológico, em 74,5% (43/51) foi isolado Corynebacterium pseudotuberculosis. Em 7,8% (4/51) foi isolado Staphylococcus aureus, em 2% (1/51) Escherichiacoli e 5,9% (3/51) amostras foram negativas. No exame histológico, em 11 linfonodos havia lesões da linfadenite caseosa caracterizadas por área de necrose central formada por lamelas concêntricas, com presença de grandes colônias bacterianas e focos de mineralização, rodeada por uma faixa de infiltrado inflamatório com macrófagos epitelióides e poucos neutrófilos. Na camada adjacente observaram-se linfócitos e plasmócitos e toda a lesão era delimitada por tecido conjuntivo fibroso. Nas outras 32 amostras foram observadas a maioria, mas não todas as lesões características da doença. Em 21 amostras foram encontradas células gigantes. As lesões histológicas dos linfonodos que foi isolado S. aureus foram semelhantes as da linfadenite caseosa. Conclui-se que as lesões histológicas de linfadenite caseosa são características, mas não patognomônicas, pois podem ser confundidas com lesões causadas por outros organismos piógenos e com tuberculose; portanto o isolamento bacteriológico é imprescindível para o diagnóstico definitivo da linfadenite caseosa.(AU)

caseous lymphadenitis (CL) in hair sheep slaughtered in an abattoir in the state of Paraíba, northeastern Brazil. From 1,466 sheep slaughtered, 236 (15.9%) had gross lesions similar to that of CL. The prevalence was higher in females, 17.9% (135/754), than in males, 13.8% (101/732). Ninety seven (36.3%) out of 268 lesions were localized in the prescapular lymph node, 22.4% (60/268) in the parotideal, and 20.9% (56/268) in the prefemoral. Only 70 (26.1%) out of 268 lesions suggestive of CL were detected during ante mortem examination. Caseous lymphadenitis-like lesions were observed in all flocks examined from different municipalities in the states of Paraíba, Pernambuco and Bahia. Cultures and histologic examination were performed in samples from 51 lesions. Corynebacterium pseudotuberculosis was isolated in 74.5% (43/51) samples, Staphylococcus aureus in 7.8% (4/51) samples, Escherichia coli in 2% (1/51), and in 5.9% (3/51) samples cultures were negative. Histologic findings in 11 lymph nodes showed all characteristic lesions of caseous lymphadenitis: central area of necrosis formed by concentric lamellae, with large bacterial colonies and mineralization, surrounded by an inflammatory exudate with epithelioid macrophages and few neutrophils; lymphocytes and plasma cells were observed in the next layer, and fibrous tissue was surrounding the whole lesion. Lesions in the other 32 lymph nodes showed most, but not all lesions characteristic of the disease. Giant cells were observed in 21 lymph nodes. Histologic lesions in lymph nodes from which S. aureus was isolated were similar as those of CL. These findings suggest that CL lesions are characteristic, but not pathognogmonic, because they can be confused with lesions caused by other pyogenic bacteria or tuberculosis; therefore bacteriologic examination is necessary for the diagnosis of the disease.(AU)