Real-time PCR detection of Brucella spp. DNA in lesions and viscera of bovine carcasses.

This study reports a real-time PCR assay for the detection of Brucella spp. associated with the FTA® Elute method in lesions observed during sanitary inspections in beef slaughter. Of the total 276 samples, 78 (28.3%) tested positive and 198 (71.7%) negative for Brucella spp. The real-time PCR technique associated with the FTA® Elute method proved to be an important tool for the diagnosis, judgment about and disposal of carcasses and viscera of slaughtered animals.

PCR and ELISA (VIDAS ECO O157(®)) Escherichia coli O157:H7 identification in Minas Frescal cheese commercialized in Goiânia, GO.

Escherichia coli O157:H7 has been incriminated in food poisoning outbreaks and sporadic cases of hemorrhagic colitis and hemolytic uremic syndrome in many countries. Considering the high susceptibility of Minas Frescal cheese to contamination by E. coli O157:H7, the aim of this study was to determine the occurrence of this pathogen through PCR (Polymerase Chain Reaction) and ELISA (VIDAS ECO O157(®), bioMérieux, Lyon, France) test. Thirty cheese samples manufactured by artisan farmhouse producers were collected from open-air markets in Goiânia and thirty from industries under Federal Inspection located in Goiás State which trade their products in supermarkets in Goiânia. E. coli O157:H7 was detected in 6.67% samples collected in open air markets using ELISA, and 23,33% with PCR. The pathogen was not detected in samples from industries under Federal Inspection.

Association of TLR4 polymorphisms with subclinical mastitis in Brazilian holsteins.

The identification of dairy cows with greater or lower potential to develop mastits has been pursued for many years among different segments of the milk industry, including governmental organizations. Genomic studies have suggested that Single Nucleotide Polymorphisms (SNPs) within the pattern recognition receptors (PRR) could lead to different responses to pathogens, and consequently result in mastitis resistance or susceptibility. To investigate whether toll like receptor 4 (TLR4) gene is associated with subclinical mastitis in Holstein cows from a property in the state of Goiás, Brazil, TaqMan allelic discrimination and somatic cell count were performed. One hundred and fifty milk samples were analyzed for SCC and centesimal composition. Twenty percent of those samples with SCC above 200,000 (n=13) were screened for real-time PCR identification of microorganisms and blood samples were genotyped for TLR4 SNPs. There was a higher prevalence of Gram-positive bacteria in the analyzed samples (88.9%) and animals that had the combined genotypes AACCCC, GGTCGG and GACCGC presented the lowest somatic cell scores, and consequently those genotypes have the potential to be applied as molecular markers for assisted animal selection to improve milk quality.

Mass mortality associated with a frog virus 3-like Ranavirus infection in farmed tadpoles Rana catesbeiana from Brazil.

Ranaviruses (Iridoviridae) are increasingly associated with mortality events in amphibians, fish, and reptiles. They have been recently associated with mass mortality events in Brazilian farmed tadpoles of the American bullfrog Rana catesbeiana Shaw, 1802. The objectives of the present study were to further characterize the virus isolated from sick R. catesbeiana tadpoles and confirm the etiology in these outbreaks. Sick tadpoles were collected in 3 farms located in Goiás State, Brazil, from 2003 to 2005 and processed for virus isolation and characterization, microbiology, histopathology, and parasitology. The phylogenetic relationships of Rana catesbeiana ranavirus (RCV-BR) with other genus members was investigated by PCR with primers specific for the major capsid protein gene (MCP) and the RNA polymerase DNA-dependent gene (Pol II). Sequence analysis and multiple alignments for MCP products showed >99% amino acid identity with other ranaviruses, while Pol II products showed 100% identity. Further diagnostics of the pathology including histology and transmission electron microscopy confirmed the viral etiology of these mass deaths. As far as we know, this is the first report of a ranaviral infection affecting aquatic organisms in Brazil. Additionally, our results suggest that American bullfrogs may have served as a vector of transmission of this virus, which highlights the potential threat of amphibian translocation in the world distribution of pathogens.

Epidemiological and clinical aspects of the first outbreak of bovine mastitis caused by Prototheca zopfii in Goiás State, Brazil.

The purpose of this survey was to describe the occurrence of bovine mastitis caused by Prototheca zopfii in Goiás State, Brazil. Samples of milk, environment and udder were taken from a herd of 120 Holstein cows. Sabourauds dextrose agar plates were incubated under aerobic conditions at 37 degrees C/96 h, for microbiological analysis. Somatic cell count and milk composition were also determined. Histological sections from two udders were stained with HE and PAS. Prototheca zopfii was identified in six cows whose milk had a watery appearance. They also showed a pronounced decrease in milk yield, fat and lactose. Pronounced infiltration of mononuclear cells, atrophy of alveoli and fibrosis were observed. The presence of this agent in other herds in the State is highly likely.