Prevalence and Characterization of Salmonella Isolated from Beef in Namibia

Abstract

The purpose of this research was to determine the prevalence of Salmonella in raw beef produced from selected commercial abbatoirs in Namibia. Methodology: A total of 9508 of beef samples from three different types of samples; meat cuts, carcass swabs and meat fluid were collected from the three local abattoirs over a period of two years starting from January 2008 to December 2009. Pre-enrichment for isolation of Salmonella was done in Buffered peptone water followed by enrichment in the Rappaport-Vassiliadis and selenite cystine broth. The isolation of Salmonella was done on Xylose Lysine Desoxycholate and Brilliant Green agar followed by biochemical confirmation and serotyping according to Kauffman-White scheme. Results: The overall prevalence of Salmonella was 0.85% for beef samples derived from meat cuts, meat fluid and carcass swabs. The prevalence of Salmonella in carcass swabs (2.67%) was significantly different (P = 0.05) from that of meat cuts (0.50%) and meat fluid (0.43%). No significant difference (P = 0.05) on the prevalence of Salmonella existed between the meat cuts and meat fluid. A total of 34 different types of Salmonella serovars were identified with S. Chester being the most frequently isolated serovars (n = 12), followed by S. Reading and S. Bredeney (n = 6) and S. Typhimurium (n = 5). Conclusions: The prevalence of Salmonella in raw beef found in this survey was lower than those observed in Sub Sahara Africa with S. Chester being the most prevalent serovar.