PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

ABSTRACT.- Coelho A.C., Pinto M.L., Coelho A.M., Aires A. & Rogrigues J. 2010. A seroepidemiological survey of Mycobacterium avium subsp. paratuberculosis in sheep from the North of Portugal. Pesquisa Veterinária Brasileira 30(11):903-908. Departamento de Ciências Veterinárias, CECAV, Universidade de Trás-os-Montes e Alto Douro, 5001-801 Vila Real Codex, Portugal. E-mail: accoelho@utad.pt The aim of this study was evaluate the risk factors for Mycobacterium avium subsp. paratuberculosis (Map) seroprevalence in sheep in the North of Portugal. The effects on seroprevalence of several variables such as individual characteristics, management practices, farm characteristics, animal health, and available veterinary services were evaluated. This information was then used in a multivariable logistic regression model in order to identify risk factors for Map seropositivity. Univariable analysis was used to screen the variables used in the logistic regression model. Variables that showed p values of <0.15 were retained for the multivariable analysis. Fifteen variables were associated with paratuberculosis in univariable analysis. The multivariable logistic regression model identified a number of variables as risk factors for seropositivity like sheep pure local and/or a cross of a local breed (OR=2.02), herd size with 31-60 head (OR=2.14), culling during the Spring-Summer season (OR=1.69) and the use of an anti-parasitic treatment such as Ivermectin as the only anti-parasitic medication (OR=5.60). Potential risk factors identified in this study support current recommendations for the control of paratuberculosis.

• Mycobacterium avium subsp. paratuberculosis

Abstract in Portuguese:

RESUMO.- Coelho A.C., Pinto M.L., Coelho A.M., Aires A. & Rogrigues J. 2010. A seroepidemiological survey of Mycobacterium avium subsp. paratuberculosis in sheep from the North of Portugal. [Rastreio seroepidemiológico de Mycobacterium avium subsp. paratuberculosis em ovinos no Norte de Portugal.] Pesquisa Veterinária Brasileira 30(11):903-908. Departamento de Ciências Veterinárias, CECAV, Universidade de Trás-os-Montes e Alto Douro, 5001-801 Vila Real Codex, Portugal. E-mail: accoelho@utad.pt Neste trabalho efectuou-se o estudo dos factores associados à seroprevalência da infecção ovina por Mycobacterium avium subspecies paratuberculosis (Map). Foram investigadas variáveis como as características individuais, práticas de maneio, características da granja, saúde animal e intervenções de sanidade efectuadas no animal. A análise multivariada de regressão logística foi usada para identificar estes factores associados com a seroprevalência da infecção. De acordo com os resultados da análise univariada associaram-se, com o resultado positivo à infecção (p<0,15), 15 variáveis. Após a aplicação do modelo de análise multivariada encontraram-se quatro factores de risco com significância estatística: rebanhos de raças autóctones e seus cruzamentos (OR=2,02); tamanho do efectivo entre 31-60 animais (OR=2,14); época de abate na Primavera-Verão (OR=1,69); uso de ivermectina como único antiparasitário (OR=5,60). Os potenciais factores de risco identificados neste estudo suportam as recomendações currentes para o controlo da paratuberculose.

Abstract in English:

ABSTRACT.- Coelho A.C., Pinto M.L., Coelho A.M. & Rodrigues J. 2009. [Comparison of two techniques of isolation of Mycobacterium avium subsp. paratuberculosis in faecal samples of ovine with clinical suspicion of paratuberculosis.] Comparação de duas técnicas de isolamento de Mycobacterium avium subsp. paratuberculosis em amostras de fezes de ovinos com suspeita clínica de paratuberculose. Pesquisa Veterinária Brasileira 29(5):415-420. Departamento de Ciências Veterinárias, Universidade de Trás-os-Montes e Alto Douro, Quinta de Prados, 5001-801 Vila Real, Portugal. E-mail: accoelho@utad.pt Paratuberculosis is a chronic enteric disease of ruminants caused by Mycobacterium avium subsp. paratuberculosis. Culture of bacteria from faeces and tissues samples constitutes one of the most effective methods of confirming the diagnosis of para-tuberculosis and the only method available to obtain strains of mycobacteria. However, this method is less sensitive and requires months of incubation before colony growth occurs. In this study, culture method was used on sheep faeces to diagnose paratuber-culosis in animals with compatible signs of the disease. A comparison of two culture media used to isolation was also investigated. Culture was positive in 2.0% of faecal samples. Isolation was obtained using Löwenstein Jensen® with mycobactin® J, and the Middlebrook® 7H11 with OADC®. The Löwenstein Jensen® with mycobactin® J was that provided highest amount of isolations. The percentages of isolation in each culture media were 2.0% (6/300) to Löwenstein Jensen® with micobactina J, and 1.0% (3/300) to Middlebrook® 7H11/OADC. The three positive samples in Middlebrook® 7H11/OADC were also positive in Löwenstein Jensen® with micobactina J. In the Middlebrook® 7H11/OADC alone there was no sample growth. The results of this study suggest that culture media of Löwenstein-Jensen® with micobactina® J is more effective for the isolation of sheep strains in Portugal.

• Paratuberculosis Mycobacterium avium subsp. paratuberculosis paratuberculose

Abstract in Portuguese:

ABSTRACT.- Coelho A.C., Pinto M.L., Coelho A.M. & Rodrigues J. 2009. [Comparison of two techniques of isolation of Mycobacterium avium subsp. paratuberculosis in faecal samples of ovine with clinical suspicion of paratuberculosis.] Comparação de duas técnicas de isolamento de Mycobacterium avium subsp. paratuberculosis em amostras de fezes de ovinos com suspeita clínica de paratuberculose. Pesquisa Veterinária Brasileira 29(5):415-420. Departamento de Ciências Veterinárias, Universidade de Trás-os-Montes e Alto Douro, Quinta de Prados, 5001-801 Vila Real, Portugal. E-mail: accoelho@utad.pt Paratuberculosis is a chronic enteric disease of ruminants caused by Mycobacterium avium subsp. paratuberculosis. Culture of bacteria from faeces and tissues samples constitutes one of the most effective methods of confirming the diagnosis of para-tuberculosis and the only method available to obtain strains of mycobacteria. However, this method is less sensitive and requires months of incubation before colony growth occurs. In this study, culture method was used on sheep faeces to diagnose paratuber-culosis in animals with compatible signs of the disease. A comparison of two culture media used to isolation was also investigated. Culture was positive in 2.0% of faecal samples. Isolation was obtained using Löwenstein Jensen® with mycobactin® J, and the Middlebrook® 7H11 with OADC®. The Löwenstein Jensen® with mycobactin® J was that provided highest amount of isolations. The percentages of isolation in each culture media were 2.0% (6/300) to Löwenstein Jensen® with micobactina J, and 1.0% (3/300) to Middlebrook® 7H11/OADC. The three positive samples in Middlebrook® 7H11/OADC were also positive in Löwenstein Jensen® with micobactina J. In the Middlebrook® 7H11/OADC alone there was no sample growth. The results of this study suggest that culture media of Löwenstein-Jensen® with micobactina® J is more effective for the isolation of sheep strains in Portugal.