Melanoma Awareness Among Medical Students.

Melanoma is the most aggressive skin cancer. Since diagnosis is visual, it is critical to evaluate if students acquire enough knowledge for early detection during medical school. To assess the melanoma knowledge of first-year (freshman) and sixth-year (senior) medical students, in a Brazilian Institution. It was a transversal and quantitative study. A questionnaire with sociodemographic data, knowledge about melanoma, and the habit of skin self-exam was filled out by medical students. A total of 128 first-year and 122 seniors students were included. All the sixth-year students knew melanoma as a skin cancer compared with 46.09% of the first-year students. Melanoma clinical characteristics were known by 30.51% of the freshman and 97.54% of seniors. However, they did not know the most usual site of melanoma occurrence (79.66% of first-year students and 24.59% of senior). About the skin self-exam, only 50% of first-year students and 53.28% of senior had the habit of doing it sometimes. Medical school was effective in providing knowledge about melanoma and its features. However, this was not reflected in an increase in the number of students that did the skin self-exam, which indicates the need for new approaches in teaching.

Comparison of antibody repertories against Staphylococcus aureus in healthy and infected dairy cows with a distinct mastitis history and vaccinated with a polyvalent mastitis vaccine.

Staphylococcus aureus is one of the pathogens most frequently isolated from cases of mastitis worldwide. To decrease the effect of S. aureus mastitis in dairy farming, alternative strategies for controlling mastitis are needed that depend on a better knowledge of cow-to-cow variations in S. aureus antibody production. The present study sought to explore the diversity of S. aureus antibodies produced by dairy cows with a distinct mastitis history and vaccinated with a polyvalent mastitis vaccine. We obtained protein extracts from S. aureus isolates derived from persistent subclinical mastitis. Proteins were fractionated using 2-dimensional gel electrophoresis and Western blotting. Then, Western blotting membranes were exposed to sera from 24 dairy cows that had been divided into the following groups: vaccinated dairy cows that were infected with S. aureus, further subdivided according to whether they (a) remained infected by S. aureus or (b) recovered from the intramammary infection; unvaccinated dairy cows infected with S. aureus; and vaccinated healthy dairy cows with no history of S. aureus mastitis. Proteins found to be reactive by Western blot were identified by mass spectrometry (MALDI/TOF-TOF). Our most important finding was that F0F1 ATP synthase subunit α, succinyl-diaminopimelate desuccinylase, and cysteinyl-tRNA synthetase were potential candidate proteins for the prevention of S. aureus mastitis. This study strengthens the notion that variations among animals should not be ignored and shows that the heterogeneity of antibody production against anti-staphylococcal antigens in animals may enable the identification of new immunotherapy targets.

Non-toxigenic strain of Clostridioides difficile Z31 reduces the occurrence of C. difficile infection (CDI) in one-day-old piglets on a commercial pig farm.

Neonatal porcine diarrhea (NPD) is a current problem on pig farms and is caused by several enteropathogens. Among them, Clostridioides difficile stands out due to its importance in piglets and zoonotic potential. A non-toxigenic strain of C. difficile (NTCD), named Z31, was previously tested in hamster and piglet experimental models as a strategy to prevent C. difficile infection (CDI). To evaluate the capacity of the strain Z31 to prevent CDI and NPD in one-day-old piglets on a commercial farm, 90 piglets from 16 litters received 1 × 106 spores of Z31 while 84 animals from the same litters served as controls. Animals were clinically evaluated, and fecal samples were collected 24 h after administration and submitted to A/B toxin detection and isolation of C. difficile. Stool samples were also submitted to rotavirus, Escherichia coli, and Clostridium perfringens detection. Administration of Z31 reduced the incidence of CDI in treated animals (7.8%) when compared to the control group (25.0%; P = 0.003). In animals that developed CDI, the intensity of diarrhea was lower in those that received Z31 than in the control group. Neonatal porcine diarrhea was reduced in treated animals when compared to untreated animals (P < 0.001). The present study suggests that Z31 can potentially be used to prevent CDI in piglets on commercial farms.

Sentinel node biopsy using blue dye and technetium99 in advanced gastric cancer: anatomical drainage and clinical application.

Lymph node metastases are an independent prognosis factor in gastric carcinoma (GC) patients. Radical lymphadenectomy can improve survival but it can also increase surgical morbidity. As a principle, sentinel node (SN) navigation surgery can avoid unnecessary lymphadenectomy without compromising prognosis. In this pilot study, 24 patients with untreated GC were initially screened for SN navigation surgery, of which 12 were eligible. Five patients had T2 tumors, 5 had T3 tumors and 2 had T1 tumors. In 33% of cases, tumor diameter was greater than 5.0 cm. Three hundred and eighty-seven lymph nodes were excised with a median of 32.3 per patient. The SN navigation surgery was feasible in all patients, with a median of 4.5 SNs per patient. The detection success rate was 100%. All the SNs were located in N1 and N2 nodal level. In 70.9% of cases, the SNs were located at lymphatic chains 6 and 7. The SN sensitivity for nodal staging was 91.6%, with 8.3% of false negative. In 4 patients who were initially staged as N0, the SNs were submitted to multisection analyses and immunohistochemistry, confirming the N0 stage, without micrometastases. In one case initially staged as negative for nodal metastases based on SN analyses, metastases in lymph nodes other than SN were found, resulting in a 20% skip metastases incidence. This surgery is a reproducible procedure with 100% detection rate of SN. Tumor size, GC location and obesity were factors that imposed some limitations regarding SN identification. Results from nodal multisection histology and immunohistochemistry analysis did not change initial nodal staging.

Sentinel node biopsy using blue dye and technetium99 in advanced gastric cancer: anatomical drainage and clinical application

Lymph node metastases are an independent prognosis factor in gastric carcinoma (GC) patients. Radical lymphadenectomy can improve survival but it can also increase surgical morbidity. As a principle, sentinel node (SN) navigation surgery can avoid unnecessary lymphadenectomy without compromising prognosis. In this pilot study, 24 patients with untreated GC were initially screened for SN navigation surgery, of which 12 were eligible. Five patients had T2 tumors, 5 had T3 tumors and 2 had T1 tumors. In 33% of cases, tumor diameter was greater than 5.0 cm. Three hundred and eighty-seven lymph nodes were excised with a median of 32.3 per patient. The SN navigation surgery was feasible in all patients, with a median of 4.5 SNs per patient. The detection success rate was 100%. All the SNs were located in N1 and N2 nodal level. In 70.9% of cases, the SNs were located at lymphatic chains 6 and 7. The SN sensitivity for nodal staging was 91.6%, with 8.3% of false negative. In 4 patients who were initially staged as N0, the SNs were submitted to multisection analyses and immunohistochemistry, confirming the N0 stage, without micrometastases. In one case initially staged as negative for nodal metastases based on SN analyses, metastases in lymph nodes other than SN were found, resulting in a 20% skip metastases incidence. This surgery is a reproducible procedure with 100% detection rate of SN. Tumor size, GC location and obesity were factors that imposed some limitations regarding SN identification. Results from nodal multisection histology and immunohistochemistry analysis did not change initial nodal staging.

Cross-reactivity of anti-human cytokine monoclonal antibodies used as a tool to identify novel immunological biomarkers in domestic ruminants.

Eleven commercially available PE-labeled anti-human (IL-1-α, IL-6, IL-8, TNF-α, IL-17A, IL-5, IL-10, IL-12 and IL-13) and anti-mouse (IL-10, TNF-α) cytokine monoclonal antibodies (mAbs) were tested for cross-reactivity with cattle, goat, and sheep cytokines. Cross-reactivity was assessed by comparative analysis with the standard reactivity of the target species. Our data demonstrated that anti-human IL-1-α, IL-6, IL-8, IL-17A and IL-10 mAbs cross-react with all ruminant species tested. Anti-human IL-5 mAb showed a strong cross-reactivity with cattle and goat IL-5, while anti-human TNF-α mAb showed a selective cross-reactivity with goat TNF-α. No cross-reactivity with the ruminant cytokines was observed for anti-human IL-12 and IL-13 mAbs or for the two anti-mouse cytokine mAbs tested. The present study demonstrated the cross-reactivity of various anti-human cytokine mAbs with cattle, sheep, and goat cytokines, increasing the range of immunological biomarkers for studies in veterinary medicine.

Validation of two real-time PCRs targeting the PE-PGRS 20 gene and the region of difference 4 for the characterization of Mycobacterium bovis isolates.

This study aimed to develop and validate real-time PCR for the diagnosis of Mycobacterium bovis isolates. Two hundred and seventy-four M. bovis isolates and 156 M. tuberculosis isolates were tested. Both qPCRs amplified all of the 274 M. bovis samples, but none of the 156 M. tuberculosis samples. The qPCR for PE-PGRS 20 had 91% efficiency and a detection limit of 0.32 ng (sensitivity and specificity for qPCR "Mbovis.100" were 99.64 and 100%, respectively). The qPCR for RD4 had 100% efficiency, and a detection limit of 4 pg (diagnostic sensitivity and specificity were 100 and 100%. The qPCR tests were performed using 4 extraction sets, 3 qPCR kits, and with a range of equipment; yet, all combinations produced similar results in a diagnostic test, demonstrating the robustness of this method. The techniques proved to be efficient, robust, sensitive, and specific for the diagnosis of M. bovis.

The prevalence of swine enteropathogens in Brazilian grower and finish herds.

Diarrhoea among growing and finishing pigs is an important problem in many herds. The prevalence of L. intracellularis, B. pilosicoli, B. hyodysenteriae, Salmonella spp., enterotoxigenic E. coli, Trichuris suis and the occurrence of mixed infection were investigated. Fecal samples for forty-six herds with diarrhea or a history of diarrhea were randomly collected in Minas Gerais state, Brazil. The enteric pathogens were detected by culture (E. coli and Salmonella sp.), PCR (L. intracellularis and Brachyspira spp.) and eggs counts (T. suis). The overall herd prevalence of L. intracellularis, Salmonella enterica serotype Typhimurium and enterotoxigenic E. coli were 19.56%, 6.52%, 10.86% respectively. Mixed infection was diagnosed in 30.43% of herds, and L. intracellularis and Salmonella enterica serotype Typhimurium are main pathogens association (10.87%). B. pilosicoli was diagnosed only in two herds, always associated with mixed infections. B. hyodysenteriae and T. suis were not demonstrated in any sample. These pathogens have been reported world-wide but studies regarding epidemiology in Brazil are few. This study contributes to establish of prevention programs for the control enteropathogens in grower finish herds in Brazil.

The prevalence of swine enteropathogens in Brazilian grower and finish herds

Diarrhoea among growing and finishing pigs is an important problem in many herds. The prevalence of L. intracellularis, B. pilosicoli, B. hyodysenteriae, Salmonella spp., enterotoxigenic E. coli, Trichuris suis and the occurrence of mixed infection were investigated. Fecal samples for forty-six herds with diarrhea or a history of diarrhea were randomly collected in Minas Gerais state, Brazil. The enteric pathogens were detected by culture (E. coli and Salmonella sp.), PCR (L. intracellularis and Brachyspira spp.) and eggs counts (T. suis). The overall herd prevalence of L. intracellularis, Salmonella enterica serotype Typhimurium and enterotoxigenic E. coli were 19.56%, 6.52%, 10.86% respectively. Mixed infection was diagnosed in 30.43% of herds, and L. intracellularis and Salmonella enterica serotype Typhimurium are main pathogens association (10.87%). B. pilosicoli was diagnosed only in two herds, always associated with mixed infections. B. hyodysenteriae and T. suis were not demonstrated in any sample. These pathogens have been reported world-wide but studies regarding epidemiology in Brazil are few. This study contributes to establish of prevention programs for the control enteropathogens in grower finish herds in Brazil.

Molecular characterization of Corynebacterium pseudotuberculosis isolated from goats using ERIC-PCR.

Corynebacterium pseudotuberculosis, the infectious agent of caseous lymphadenitis (CLA), is responsible for substantial economic losses in goat and sheep production. Molecular characterization of C. pseudotuberculosis isolates by enterobacterial repetitive intergenic consensus (ERIC)-PCR has shown promising results in genotyping strains isolated from sheep with CLA. We evaluated the genetic diversity of C. pseudotuberculosis isolates collected from the Sertão region of the Pernambuco (PE) State, Brazil, and investigated the potential of ERIC-PCR as a tool for the molecular typing of strains of C. pseudotuberculosis isolated from goats. Thirty-two C. pseudotuberculosis strains isolated from goats in the municipalities of Floresta and Ibimirim, PE, C. pseudotuberculosis type strain ATCC 19410, the 1002 vaccine strain, and a field isolate of Rhodococcus equi were fingerprinted using the primers ERIC-1R and ERIC-2 and the primer pair ERIC- 1R+ERIC-2. Using 100% similarity as the cutoff, 8, 10, and 7 genotypes were obtained with ERIC-1-PCR, ERIC-2-PCR, and ERIC-1+2-PCR, respectively. The Hunter-Gaston discriminatory index calculated for the ERIC-1-PCR was 0.75. The index for the ERIC-2-PCR was 0.88, and the index for the ERIC-1+2-PCR was 0.79. Among goat isolates of C. pseudotuberculosis, three, two and four genotypes (found by ERIC-1-PCR, ERIC-2-PCR, and ERIC-1+2-PCR, respectively) had been previously described among sheep isolates from Minas Gerais State, Brazil. These results showed that ERIC-PCR has good discriminatory power and typeability, making it a useful tool for discrimination among C. pseudotuberculosis isolates from goats.

A comparison of two agar gel immunodiffusion methods and a complement fixation test for serologic diagnosis of Brucella ovis infection in experimentally infected rams / Comparação entre dois métodos de imunodifusão em gel de Agar e um método de fixação de complemento para o diagnóstico sorológico da infecção por Brucella ovis em carneiros experimentalmente infectados

A infecção por Brucella ovis é considerada uma das principais causas de epididimite e infertilidade em carneiros, resultando em falhas reprodutivas e perdas econômicas significativas em rebanhos ovinos ao redor do mundo. O estudo teve o objetivo de avaliar três testes sorológicos disponíveis para o diagnóstico da brucelose ovina por B. ovis, utilizando 181 soros ovinos. Amostras de soro provenientes de carneiros experimentalmente infectados foram coletadas ao longo de 192 dias pós-infecção (n=117) e durante o período pré-infecção (n=9). Adicionalmente, amostras de soro foram obtidas de ovinos provenientes de um rebanho livre para B. ovis (n=55). As técnicas de imunodifusão em gel de agar (IDGA), utilizando dois antígenos disponíveis comercialmente, e de fixação de complemento foram comparadas (FC). Foram obtidos resultados de sensibilidade especificidade semelhantes para ambos os métodos de IDGA e ainda, a técnica de IDGA foi mais eficiente do que a da FC para o diagnóstico sorológico da infecção por B. ovis.

Campilobacteriose genital bovina e tricomonose genital bovina: epidemiologia, diagnóstico e controle / Bovine genital campylobacteriosis and bovine genital trichomonosis: epidemiology, diagnosis and control

A presente atualização trata de duas das mais importantes doenças sexualmente transmitidas de bovinos, a campilobacteriose genital bovina e a tricomonose genital bovina. São abordados aspectos relacionados à epidemiologia destas doenças, principalmente em relação a sua distribuição no Brasil. Também são revisados aspectos importantes de diagnóstico, incluindo as técnicas e interpretação dos resultados, além de medidas de controle para ambas as doenças.

The present update deals with two of the most important sexually transmitted diseases of cattle: bovine genital campylobacteriosis and bovine genital trichomonosis. Epidemiological aspects, mainly their distribution in Brazil, alongside with their diagnosis in cattle are presented and commented. The main points in their diagnoses, including the description of the techniques and the interpretation of the results are also reviewed. Finally the control and prevention of both diseases are discussed.

High seroprevalence of caseous lymphadenitis in Brazilian goat herds revealed by Corynebacterium pseudotuberculosis secreted proteins-based ELISA.

We conducted a seroepidemiological survey to determine the prevalence of caseous lymphadenitis (CLA) in goat herds in Minas Gerais state, Brazil. Serum samples were collected from goats (n=676) from 108 rural properties in 2001, covering most of the sub-regions of this ca. 586,500 square kilometer state. Antibodies against Corynebacterium pseudotuberculosis secreted proteins were detected by an indirect enzyme-linked immunosorbent assay (ELISA). Most of the animals (78.9%) tested positive for CLA; 98% of flocks presented at least one seropositive animal. Goats managed under an extensive production system had a significantly higher seroprevalence of CLA than those in intensive and semi-intensive operations. The age distribution of the animals in the flocks affected the prevalence of this disease; however, goat breed did not. We found seropositivity against C. pseudotuberculosis to be highly prevalent in these Brazilian goat herds; consequently, appropriate management practices for the control of CLA should be implemented.

Estudos de prevalência da brucelose bovina no âmbito do Programa Nacional de Controle e Erradicação de Brucelose e Tuberculose: Introdução / Prevalence studies on bovine brucelosis according to Brazilian National Program for the Control and Eradication of Bovine Brucellosis and Tuberculosis: Introduction

As estratégias de combate à brucelose bovina são bastante conhecidas e, até o momento, os resultados são divergentes. No Brasil, o Ministério da Agricultura, Pecuária e Abastecimento (MAPA) implementou, em 2001, o Programa Nacional de Controle e Erradicação da Brucelose e Tuberculose. Conhecer a situação epidemiológica da brucelose no início de um programa de controle permite: 1 - escolher as melhores estratégias de controle em função da frequência e padrão de distribuição da doença na população e 2 - acompanhar o programa com a finalidade de promover correções e evitar o desperdício de tempo e de recursos. Em razão disso, é necessário realizar estudos para dar suporte à escolha das melhores estratégias para os vários estados e regiões brasileiras e criar um mecanismo racional de verificação da efetividade das ações implementadas. Para tanto, o MAPA estabeleceu um Termo de Cooperação Técnica com a Faculdade de Medicina Veterinária da Universidade de São Paulo e envolveu também a Faculdade de Agronomia e Veterinária da Universidade de Brasília. Até o momento, foram concluídos os estudos de 15 unidades federativas, cujos resultados são apresentados nos artigos subsequentes. Além disso, há um 16º artigo que explora o impacto da vacinação de bezerras com a B19 na redução da prevalência da brucelose.

Although strategies for controlling and eradicating of bovine brucellosis are well known, the achievements vary widely. In 2001, the Brazilian Ministry of Agriculture, Livestock, and Food Supply (MAPA) started a new National Program for the Control and Eradication of Brucellosis and Tuberculosis (NPCEBT). In the beginning of a brucellosis control program, it is of utmost importance to gain insights into the epidemiological status of the disease in order to: (1) determine the sanitary measures according to the frequency and distribution patterns of the disease in the population; (2) monitor the development of the program and decide when to make adjustments, avoiding the waist of time and resources. As the epidemiological status of bovine brucellosis is not adequately known in Brazil, there was a case for undertaking cross-sectional studies targeted at identifying the best strategies for each state and region, as well as providing a basis for future appraisal of the NPCEBT. For this purpose, MAPA established a collaborative project with FMVZ-Universidade de São Paulo, which also included FAV-Universidade de Brasília. So far, 15 states completed the survey, whose results are described in the following papers. In addition, it is presented a paper that deals with modeling the impact of vaccination of heifers with strain 19 upon the reduction of brucellosis prevalence.

Estudos de prevalência da brucelose bovina no âmbito do Programa Nacional de Controle e Erradicação de Brucelose e Tuberculose: Introdução / Prevalence studies on bovine brucelosis according to Brazilian National Program for the Control and Eradication of Bovine Brucellosis and Tuberculosis: Introduction

As estratégias de combate à brucelose bovina são bastante conhecidas e, até o momento, os resultados são divergentes. No Brasil, o Ministério da Agricultura, Pecuária e Abastecimento (MAPA) implementou, em 2001, o Programa Nacional de Controle e Erradicação da Brucelose e Tuberculose. Conhecer a situação epidemiológica da brucelose no início de um programa de controle permite: 1 - escolher as melhores estratégias de controle em função da frequência e padrão de distribuição da doença na população e 2 - acompanhar o programa com a finalidade de promover correções e evitar o desperdício de tempo e de recursos. Em razão disso, é necessário realizar estudos para dar suporte à escolha das melhores estratégias para os vários estados e regiões brasileiras e criar um mecanismo racional de verificação da efetividade das ações implementadas. Para tanto, o MAPA estabeleceu um Termo de Cooperação Técnica com a Faculdade de Medicina Veterinária da Universidade de São Paulo e envolveu também a Faculdade de Agronomia e Veterinária da Universidade de Brasília. Até o momento, foram concluídos os estudos de 15 unidades federativas, cujos resultados são apresentados nos artigos subsequentes. Além disso, há um 16º artigo que explora o impacto da vacinação de bezerras com a B19 na redução da prevalência da brucelose.

Although strategies for controlling and eradicating of bovine brucellosis are well known, the achievements vary widely. In 2001, the Brazilian Ministry of Agriculture, Livestock, and Food Supply (MAPA) started a new National Program for the Control and Eradication of Brucellosis and Tuberculosis (NPCEBT). In the beginning of a brucellosis control program, it is of utmost importance to gain insights into the epidemiological status of the disease in order to: (1) determine the sanitary measures according to the frequency and distribution patterns of the disease in the population; (2) monitor the development of the program and decide when to make adjustments, avoiding the waist of time and resources. As the epidemiological status of bovine brucellosis is not adequately known in Brazil, there was a case for undertaking cross-sectional studies targeted at identifying the best strategies for each state and region, as well as providing a basis for future appraisal of the NPCEBT. For this purpose, MAPA established a collaborative project with FMVZ-Universidade de São Paulo, which also included FAV-Universidade de Brasília. So far, 15 states completed the survey, whose results are described in the following papers. In addition, it is presented a paper that deals with modeling the impact of vaccination of heifers with strain 19 upon the reduction of brucellosis prevalence.

Pathological, immunohistochemical and bacteriological study of tissues and milk of cows and fetuses experimentally infected with Brucella abortus.

This report describes a pathological, immunohistochemical and bacteriological study of 42 cows and their progeny (aborted fetuses, weak premature calves, and healthy full-term calves) infected at 6-7 months of gestation by conjunctival inoculation with Brucella abortus. Samples were collected at necropsy within 48 h of abortion or parturition. The most significant lesions were necrotizing and suppurative placentitis and lymphohistiocytic mastitis in cows, and fibrinous pleuritis, fibrinous pericarditis and bronchopneumonia in aborted fetuses. B. abortus was isolated more frequently from milk samples than from mammary tissues, and milk samples from cows with mastitis were often infected. Organisms were often demonstrated immunohistochemically and by culture in tissues showing moderate to severe histological changes.

Detecção de cepas patogênicas pela PCR multiplex e avaliação da sensibilidade a antimicrobianos de Escherichia coli isoladas de leitões diarréicos / Detection of pathogenic strains by multiplex PCR and antimicrobial sensitivity of Escherichia coli isolated from piglets

Avaliou-se a freqüência dos genes de fímbrias (K88, K99, 987P, F18 e F41) e toxinas (LT, Stb, StaP e Stx2e) de cepas de E. coli isoladas de leitões com diarréia usando a técnica de PCR multiplex com primers específicos para esses genes, e estudou-se o padrão de sensibilidade das cepas patogênicas pelo método de difusão em disco ao florfenicol, ceftiofur sódico, colistina, fosfomicina, neomicina, norfloxacina, sulfa + trimetoprim, doxiciclina, tetraciclina e lincomicina. Foram utilizadas 144 amostras de E.coli isoladas de leitões com diarréia, provenientes de granjas localizadas no estado de Minas Gerais. Dessas, 42 (29,2 por cento) foram positivas para pelo menos um dos fatores de virulência testados. Dentre essas 42 amostras, 23 (54,8 por cento) apresentaram genes de fímbria e toxina, sete (16,6 por cento) apresentaram somente genes de toxinas e 12 (28,6 por cento) amostras somente genes de fímbria. O resultado do teste de sensibilidade aos antimicrobianos demonstrou que o florfenicol (89,5 por cento) e o ceftiofur sódico (84,2 por cento) foram as drogas de melhor eficácia in vitro sobre cepas de E. coli com fatores de virulência

The frequency of virulence determinants genes for fimbrial adhesions (K88, K99, 987P, F18 and F41) and toxins (LT, Stb, StaP and Stx2e) in E. coli strains isolated from diarrheic piglets using the multiplex polymerase chain reaction assay with specific primers for these genes was studied. The antimicrobial sensitivity pattern of pathogenic isolates for florfenicol, sodium ceftiofur, colistin, fosfomycin, neomycin, norfloxacin, sulfa + trimetoprim, doxycycline, tetracycline and lincomycin was also tested using the disk diffusion method. E. coli were isolated from 144 diarrheic piglets from farms in the state of Minas Gerais. Forty-two out of 144 studied samples (29.2 percent) were positive for at least one tested virulence factor. Out of these 42, 23 samples (54.8 percent) contained fimbria and toxin genes, seven (16.6 percent) samples had genes for toxins only and 12 (28.6 percent) samples just fimbria genes. Disk diffusion in vitro antimicrobial sensitivity test demonstrated the best results for florfenicol (89.5 percent) and sodium ceftiofur (84.2 percent) against virulent E. coli strains

Avaliação do tratamento com isoniazida em bovinos infectados naturalmente pelo Mycobacterium bovis / Evaluation of the treatment with isoniazid carried out in bovines naturally infected with Mycobacterium bovis

Foi adotado o tratamento intermitente da tuberculose com isoniazida em 240 bovinos de um rebanho naturalmente infectado pelo M. bovis. No início do tratamento 36,6 por cento dos animais foram reagentes positivos e 2,9 por cento inconclusivos. Todos os animais do rebanho receberam isoniazida por via oral em doses de 25mg/kg de peso vivo, administrada três vezes por semana, às segundas, quartas e sextas-feiras, durante 10 meses, perfazendo 120 doses. A cura de 98,9 por cento dos animais tratados foi verificada por meio da dessensibilização alérgica realizada pela tuberculinização e controle bacteriológico de 39 animais abatidos. O tratamento neste rebanho não resultou em seleção de cepas resistentes a isoniazida, comprovada pelo teste de sensibilidade a essa droga, realizado em cultura de M. bovis isolada de um animal não curado.

Passive immunity in cattle against enterotoxigenic Escherichia coli: serologic evaluation of a bacterin containing K99 and F41 fimbriae in colostrum of vaccinated females and calf serum

Produziu-se uma bacterina de Escherichia coli enterotoxigênica (ETEC) contendo as fímbrias K99 e F41 e avaliaram-se a capacidade de indução de anticorpos anti-K99 e anti F-41 no colostro de vacas vacinadas e no soro de bezerros e a persistência dos anticorpos nos neonatos. Três experimentos foram realizados em duas fazendas comerciais. Os animais foram aleatoriamente alocados em blocos, de duas fêmeas prenhes (uma vacinada e outra controle) e seus respectivos bezerros. No experimento A (fazenda 1), com 18 blocos, os animais receberam uma dose da vacina, 30 dias antes do parto. No experimento B (fazenda 1), com 26 blocos, os animais receberam duas doses de vacina, aos 60 e 30 dias antes do parto. No experimento C (fazenda 2), com 22 blocos, os animais receberam o mesmo esquema de vacinação do experimento B. Nos experimentos A e B foram coletados colostro das parturientes e soro dos bezerros entre 24 e 36 horas de vida. No experimento C, foram usadas novilhas receptoras de embriões e coletados colostro e soro dos bezerros aos 7, 14, 28 e 42 dias de idade. Anticorpos anti-K99 e anti-F41 foram detectados por ELISA utilizando antígenos K99 e F41 purificados. No experimento A não foi observada diferença entre o grupo vacinado e o controle quanto à detecção de anticorpos. No experimento B foi observada diferença (P<0,001) entre o colostro de fêmeas vacinadas e o soro de seus bezerros. No C houve diferença entre o grupo vacinado e o controle para o colostro e o soro dos bezerros aos 7, 14, 28 (P<0,001) e 42 dias de idade (P= 0,003). A bacterina utilizada foi eficiente para a indução de resposta imune humoral detectável.

Campilobacteriose genital bovina em rebanhos leiteiros com problemas reprodutivos da microrregião de Varginha - Minas Gerais / Bovine genital campylobacteriosis in dairy herds with reproductive problems of the microregion of Varginha, MG, Brazil

The frequency of bovine genital campylobacteriosis (BGC) in 157 cows from nine herds from the microregion of Varginha - Minas Gerais - Brazil was evaluated. Farmers use either artificial insemination and natural breeding after two insemination procedures or natural breeding. The diagnosis of BGC was performed by the direct fluorescent antibody test (DFAT) using vaginal mucus. All studied herds showed C. fetus infected animals and, of 157 animals, 40 (25.5 percent) were positive in DFAT: 7 (26.9 percent) from herds with natural breeding and 33 (25.1 percent) from herds with both artificial insemination and natural breeding after the second-to-third insemination. The high frequency of BGC found in this study shows that this disease is present among herds which have reproductive problems and the use of natural breeding after the second-to-third unsuccessful insemination could be a risk factor for the disease