Identification of Salmonella species in chicken eggs sold in Port Harcourt

Abstract

Chicken eggs are a staple food consumed by people worldwide, but they can serve as reservoirs for foodborne pathogens, including various Salmonella species, posing significant risks to public health. This study investigated the prevalence and incidence of Salmonella in chicken eggs sourced from 7 poultry farmhouses and 7 supermarket retailers in Ozuoba axis of Obio/Akpor Local Government Area, Port Harcourt, Rivers State, Nigeria. Total Heterotrophic Bacteria (THB) counts for egg samples showed higher counts on the eggshell surface (ESS) compared to the inner content (INC) and also showed higher Salmonella counts on the ESS compared to INC. Prevalence/percentage occurrence of Salmonella enteritidis, S. enterica, S. typhimurium, S. gallinarum and S. parataphi were found to be 28%, 24%, 20%, 16% and 12%, respectively. Additionally, other bacteria species were identified from nutrient agar plates predominantly found on eggshell surfaces such as Escherichia coli, Bacillus sp., Staphylococcus sp. and Streptococcus sp. Furthermore, the nutritional composition of egg components and their pH levels that influence bacterial growth was examined. The results suggest that while egg white contains antimicrobial proteins inhibiting bacterial growth, egg yolk's rich nutrient content may support microbial proliferation if contaminated. These findings emphasize the importance of stringent food safety regulations, including proper hygiene practices during egg production, handling, and distribution, to mitigate the risk of Salmonella contamination. Public health interventions such as consumer education on safe food handling practices and regular monitoring of foodborne pathogens in chicken eggs are essential for preventing foodborne illnesses and protecting public health in the Port Harcourt metropolis and beyond.

Keywords: Salmonella, chicken eggs, foodborne disease, food safety, public health.