Resumo
In 2003, Brazil was recognized as a pathogenic Newcastle Disease Virus (NDV) strain-free country for commercial poultry. This research was conducted in Brazil between December 2003 and March 2005 to verify the maintenance of this virulent NDV-free status. Serum samples from 5,455 flocks for commercial poultry farms were collected, comprising 81,825 broiler chickens. The farms were located in nine states of the country, grouped in three geographic regions. Serological evidence of NDV infection was detected in 28.8% of the surveyed farms. However, all fifteen viruses isolated and identified as Newcastle Disease Virus (NDV) were characterized as nonpathogenic strains, based on the Intracerebral Pathogenicity Index. These results showed that Brazil preserves the virulent NDV-free status for commercial flocks.
Resumo
This study was carried out during 2002/2003, aiming to determine the prevalence of virulent Newcastle disease virus strains (NDV) in Brazilian commercial poultry farms. Clinical samples were obtained from the Southeastern, Southern and Central-Western regions, which comprise the main area of the Brazilian poultry production. Serum samples and tracheal and cloacal swabs of 23,745 broiler chickens from 1,583 flocks, including both vaccinated chickens and those with no vaccination information, were tested for NDV using a diagnostic ELISA kit. The seropositivity was 39.1%, and the isolation percentage by flock varied from 1.0 to 7.6%, and by region from 6.5 to 58.4%. Higher isolation rates (74.3-83.3%) were obtained after three passages in embryonated chicken eggs. All isolates preliminarily identified as NDV were characterized as nonpathogenic strains, as their Intracerebral Pathogenicity Index (ICPI) was below 0.7. Based on results of this study, Brazil can claim a virulent NDV-free status for commercial flocks.
Resumo
The occurrence of Salmonella in a samples of 40 imported day-old duckling flocks was assessed from 1998 to 2003 according to the guidelines of the Brazilian National Poultry Health Program (Programa Nacional de Sanidade Avícola-PNSA). The pathogen was recovered from 26 flocks (65.0%). The most common serovars were S. Saintpaul and S. Kottbus. Up to four serovars were isolated from a single flock. Transportation box swabs (82.6%) and yolk sac pool (47.1%) showed the highest and the lowest frequency of Salmonella isolation, respectively. The high percentage of Salmonella isolation from imported day-old ducklings causes concern because of the zoonotic potential of this agent and its economical importance to commercial poultry breeding.
Resumo
The occurrence of Salmonella in a samples of 40 imported day-old duckling flocks was assessed from 1998 to 2003 according to the guidelines of the Brazilian National Poultry Health Program (Programa Nacional de Sanidade Avícola-PNSA). The pathogen was recovered from 26 flocks (65.0%). The most common serovars were S. Saintpaul and S. Kottbus. Up to four serovars were isolated from a single flock. Transportation box swabs (82.6%) and yolk sac pool (47.1%) showed the highest and the lowest frequency of Salmonella isolation, respectively. The high percentage of Salmonella isolation from imported day-old ducklings causes concern because of the zoonotic potential of this agent and its economical importance to commercial poultry breeding.