Prevalence and quantitative detection of Salmonella in retail raw chicken in Shaanxi, China

Quantitative Salmonella concentrations and prevalence of Salmonella in raw chicken at the retail level in Shaanxi province, China, was determined in this study. Two hundred forty samples were collected in Yangling and the surrounding cities, in Shaanxi Province, China, for data collection over 12 successive months from April 2011 to March 2012. During the whole surveillance year, the overall Salmonella contamination rate of retail raw chicken was identified as 43.3%, the most-probable-number (MPN) values ranged from 0.0036 to 0.8596 MPN per g, and the average value was 0.1655 MPN per g, except in 11 of the samples, which had MPN values of more than 11 MPN per g. In April 2011, the highest prevalence rate, which was 80.0%, was observed, and the corresponding MPN value was 0.8596 MPN per g. Observed in November 2011, the lowest prevalence rate and the corresponding MPN value were 5.0% and 0.0036 MPN per g, respectively. Prevalence of Salmonella in chicken collected from the supermarket (49.2%) was higher but not significantly different from that in the wet markets (37.5%), although the MPN value of samples in the wet market (0.1912 MPN per g) was higher than that in the supermarket (0.1396 MPN per g). Prevalence of Salmonella was the highest in the frozen chicken (53.3%) compared with chilled chicken (45.0%) and freshly slaughtered chicken (37.5%); however, the MPN value of the freshly slaughtered chicken (0.1912 MPN per g) was higher than those of either frozen chicken (0.1804 MPN per g) or the chilled chicken (0.0988 MPN per g).