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.

Co-occurrence of aflatoxins B1, B2, G1, G2, zearalenone and fumonisin B1 in Brazilian corn

Abstract: Two hundred and fourteen unprocessed corn samples (1997–98 harvest), collected at wholesale markets in different regions in Brazil, were surveyed for the occurrence of mycotoxins. The samples were analysed for aflatoxins B1, B2, G1, G2, zearalenone and fumoni1sin B1 using in-house validated methods. The occurrence of aflatoxin B1, zearalenone and fumonisin B1 was found in 38.3, 30.4 and 99.1% of the samples, respectively. Aflatoxin B1, zearalenone and fumonisin B1 contamination levels varied from 0.2 to 129, 36.8 to 719, and 200 to 6100 μg/kg, respectively. The cooccurrence of the two carcinogenic mycotoxins aflatoxin B1 and fumonisin B1 was observed in 100% of the aflatoxin-contaminated samples (82 samples). Cooccurrences of aflatoxin B1: zearalenone: fumonisin B1 and aflatoxin B1: aflatoxin B 2: fumonisin B1 were found in 18 and 43 samples, respectively.

Assessment of diagnostic tools for eradication of bovine tuberculosis in cattle co-infected with Mycobacterium bovis and M. avium subsp. paratuberculosis.

Abstract: The intradermal tuberculin (IDTB) test and the interferon-gamma (IFN-$\gamma$) assay are used worldwide for detection of bovine tuberculosis in cattle, but little is known about the effect of co-infecting agents on the performance of these diagnostic tests. This report describes a field trial conducted in a cattle herd with dual infection (bovine tuberculosis and paratuberculosis) during 3.5 years. It has been based on a strategic approach encompassing serial parallel testing (comparative IDTB test, the IFN-$\gamma$ assay and serology of paratuberculosis) that was repeated 8 times over the period, and segregation of animals into two herds. The IDTB test detected 65.2% and the IFN-$\gamma$ test detected 69.6% of the Mycobacterium bovis culture-positive cattle. However, the IDTB test performed better during the first part of the trial, while the IFN-$\gamma$ test was the only method that detected infected animals during the following three samplings. The number of false positive reactors with the IDTB and/or the IFN-$\gamma$ tests was remarkably high compared to other reports, and could be caused by cross-reactivity with M. avium subsp. paratuberculosis. Also, the M. bovis isolates from cattle and wildlife from the same property were characterised using molecular techniques to disclose an epidemiological link. The IDTB test may not be appropriate to eradicate bovine tuberculosis in herds with dual mycobacterial infections. This report highlights the need to use several diagnostic techniques for the accurate detection of M. bovis infected animals in these herds.