Ministry of Agriculture

About: Ministry of Agriculture is a government organization based out in Rio de Janeiro, Brazil. It is known for research contribution in the topics: Biology & Chemistry. The organization has 1153 authors who have published 1189 publications receiving 14442 citations.

OCORRÊNCIA DE Campylobacter EM GRANJAS E ABATEDOURO AVÍCOLAS NA MESORREGIÃO METROPOLITANA DE BELÉM, PA, BRASIL

Abstract: The aim of the present study was to observe the occurrence of Campylobacter in chicken farms and in a slaughterhouse. A total of 120 samples were collected in three chicken farms: cloacal swabs (n=30), poultry litter (n=30), feed (n=30) and water (n=30) samples. In the slaughterhouse, 126 samples were collected: water samples (n=36), neck and chest skins (n=30), livers (n=30) and gizzards (n=30). Campylobacter was isolated in 40 (33.33%) chicken farm samples: 29 (96.6%) cloacal swabs, ten (33.3%) poultry litter and one (3.3%) water sample. Campylobacter jejuni was identified in 33 (82.5%) strains from chicken farms. In the slaugtherhouse, all the eleven (8.73%) isolated strains were identified as C. jejuni: ten (27.8%) water samples and one (3.3%) gizzard sample. The main contamination sources in chicken farms were the cloacal swabs, the poultry litter and, in small proportion, the water. In the slaughterhouse, the main critical points were the water from poultry evisceration and the gizzard collected from the small cooling tank. KEY WORDS: Campylobacter, chicken farm, slaughterhouse.

Padronização da titulação da toxina épsilon de Clostridium perfringens tipo D em linhagem contínua de células como alternativa ao bioensaio animal

Abstract: Enterotoxemia, tambem chamada de doenca do rim pulposo, doenca que acomete os ruminantes domesticos, e causada pela acao da toxina epsilon produzida pelo Clostridium perfringens tipo D, um anaerobio comumente isolado do solo e das fezes de animais sadios. O metodo tradicional de diagnostico baseia-se na deteccao e classificacao dessa exotoxina no conteudo intestinal por meio da soroneutralizacao em camundongos. Com isso, o objetivo deste estudo foi padronizar um teste para deteccao e titulacao dessa toxina in vitro e compara-lo ao fenomeno in vivo. Para isso, uma partida de toxina epsilon de Clostridium perfringens tipo D foi titulada em camundongos e em varias linhagens continuas de celulas. Apos a determinacao da linhagem celular mais sensivel, realizaram-se ensaios de titulacao in vitro de diluicoes de uma partida de toxina, comparando-os com os titulos in vivo conhecidos. Os resultados foram agrupados, e foi desenvolvida a equacao matematica que melhor adaptou-se aos intervalos trabalhados. A linhagem MDCK, alem de mais sensivel, demonstrou que o fenomeno observado in vitro pode ser expresso por meio da equacao matematica que apresenta uma correlacao de 98,33%, com a dose minima mortal determinada in vivo. Portanto, a linhagem MDCK permite titular a toxina epsilon de C. perfringens tipo D de forma especifica e sensivel, alem de ser uma tecnica pratica, rapida e que dispensa o uso de animais.

Parameter estimation and use of gamma interferon assay for the diagnosis of bovine tuberculosis in Brazil

Abstract: This study aimed to evaluate the interference of tuberculin test on the gamma-interferon (INFg) assay, to estimate the sensitivity and specificity of the INFg assay in Brazilian conditions, and to simulate multiple testing using the comparative tuberculin test and the INFg assay. Three hundred-fifty cattle from two TB-free and two TB-infected herds were submitted to the comparative tuberculin test and the INFg assay. The comparative tuberculin test was performed using avian and bovine PPD. The INFg assay was performed by the BovigamTM kit (CSL Veterinary, Australia), according to the manufacturer's specifications. Sensitivity and specificity of the INFg assay were assessed by a Bayesian latent class model. These diagnostic parameters were also estimate for multiple testing. The results of INFg assay on D0 and D3 after the comparative tuberculin test were compared by the McNemar's test and kappa statistics. Results of mean optical density from INFg assay on both days were similar. Sensitivity and specificity of the INFg assay showed results varying (95% confidence intervals) from 72 to 100% and 74 to 100% respectively. Sensitivity of parallel testing was over 97.5%, while specificity of serial testing was over 99.7%. The INFg assay proved to be a very useful diagnostic method.

Modelling uncertainty estimation for the determination of aflatoxin M1 in milk by visual and densitometric thin-layer chromatography with immunoaffinity column clean-up

Abstract: The uncertainty of aflatoxin M1 concentration in milk, determined by thin-layer chromatography (TLC) with visual and densitometric quantification of the fluorescence intensities of the spots, was estimated using the cause-and-effect approach proposed by ISO GUM (Guide to the expression of uncertainty in measurement) following its main four steps. The sources of uncertainties due to volume measurements, visual and densitometric TLC calibration curve, allowed range for recovery variation and intermediary precision to be taken into account in the uncertainty budget. For volume measurements the sources of uncertainties due to calibration, resolution, laboratory temperature variation and repeatability were considered. For the quantification by visual readings of the intensity of the aflatoxin M1 in the TLC the uncertainty arising from resolution calibration curves was modelled based on the intervals of concentrations between pairs of the calibration standard solutions. The uncertainty of the densitometric TLC ...