Microbial and Heavy Metal Assessment of Meat Samples from Ranched and Non-ranched Domestic Animals Sold at Gariki Market, Enugu State, Nigeria

Abstract

Studies were carried out to evaluate the microbial and heavy metal contamination of meat samples from ranched and non-ranched domestic animals sold at Gariki market, Enugu State, using standard analytical and biochemical procedures and instrumentation.

The meat samples from the ranched and non-ranched domestic animals (goat, cow, pig and chicken) were procured at slaughter from the Gariki market and under ice condition transported to the laboratory for microbial and heavy metal analysis. Ranched goat meat, non-ranched goat meat, non-ranched cow meat, ranched cow meat, indoor-reared pork meat, out-door reared chicken meat and in-door reared chicken meat samples had mean Cd values ranging from 0.110- 0.292 µg/g; Pb, 0.176 -0.505µg/g and Cu, 1.303 -5.972µg/g.

The mean levels of the investigated heavy metals in the meat samples were statistically significant. Meat samples procured from the non- ranched domestic animals and some ranched or in-door reared ones (cow and pig) had mean Cd levels at toxic level. Mean Pb value in the non –ranched cow meat samples followed the same trend.

The pathogenic bacteria of interest to food scientists namely, S. aureus, Streptococcus spp. and Salmonella enteritidis were isolated in the meat samples from the domestic animals. The range of mean bacterial counts of S.aureus, Streptococcus spp. and Salmonella enteritidis in the ranched goat meat, non-ranched goat meat, non –ranched cow meat, ranched cow meat, in-door-reared pork meat, out-door reared chicken meat and in-door reared chicken meat samples were 1.04 × 10² – 1.73× 10 ⁸ Cfu/g. 1.14×10² – 2.64 × 10⁶ Cfu/g and 0.82 ×10² -3.92×10⁵ Cfu/g respectively. With the inclusion of ranched cow meat and in-door reared pork meat samples, the meat samples from the non-ranched domestic animals had mean bacterial counts of the isolated pathogenic organisms above threshold limits. The quality of meat samples from the non-ranched (out-door reared) domestic animals sold at Gariki market, could be said to be more burdened by heavy metal and microbial contamination, which apart from decreasing the nutritive quality of the meats, also portends food safety challenges to the consumers.