Prevalence and molecular characterization of non-typhoidal Salmonella in poultry of Dar es salaam, Tanzania

Abstract

Poultry is one of the common source of non-typhoidal Salmonella and poultry products are the major sources of human and animal infections with the Salmonella. A cross-sectional study was conducted to determine the prevalence of non-typhoidal Salmonella in live commercial and backyard chickens from retail markets and farms in Dar es Salaam city, Tanzania. The study was conducted in four districts; Ubungo, Kinondoni, Temeke and Ilala. A total of 400 chickens (120 broilers, 120 layers and 160 backyard chickens) were tested for Salmonella. Salmonella isolation and identification was carried out using bacteriological standard methods and polymerase chain reaction (PCR) targeting Salmonella specific invA gene of 118 bp. The descriptive statistics analysis was conducted using R-Software, and p ˂ 0.05 was considered statistically significant. Overall, 8% (N=32) of 400 chickens tested Salmonella positive. The prevalences of Salmonella in broilers, layers and backyard chickens were 15%, 7.5% and 3.1%, respectively. The proportions of Salmonella serovars detected were 78%, 16% and 3% for S. gallinarum, S. typhimurium and S. hadar, respectively. The findings confirmed Salmonella contamination in healthy chickens from markets and farms, this creates high chance for zoonotic transmission through ingestion of contaminated poultry meat. Hence call up for more researches and surveillance to monitor the risk associated with Salmonella infection for appropriate control measures.