PREVALENCE OF LISTERIA MONOCYTOGENES IN FRESH RAW MILK AND ABATTOIR EFLUENTS IN NIGERIA

Abstract

This Study investigated the prevalence of Listeria monocytogenes a foodborne
pathogen isolated from fresh rmv milk and abattoir ejJluent from the six geo-political
zones of Nigeria namely Southwest, Southeast, Southsouth, Northwest, Northeast
and Northcentral. The total samples which consisted of 305 fresh raw milk and 31
abattoir ejJluents were examined for the presence of Listeria spp. using selective

,

enrichment and isolation protocol. Listeria monocytogenes strains were identified

by biochemical tests using Brilliance Listeria chromogenic agar, Oxoid Biochemical
Identification System Mono (ORIS Mono), Rapid Listeria test kit and Polymerase
Chain Reaction (peR) method. The results obtained showed that 54 isolates (8.63%)
were identified as Listeria monocytogenes with the milk samples constituting 23
(7.54%) while abattoir ejJluent had 31 (9.65%). Statistical analysis of the results
showed that the prevalence rate of this pathogen across the zones were Southwest (
10.6%), Southeast (8.0%), Southsouth(7.9%), Northwest 11.5%), Northeast (7.9%),
Northcentral (7.4%) while the national prevalence rate was 8.6%. This indicated the
high rate of contamination of (his pathogen ill dairy and meat products. It also
showed the health hazard associated with such food. This study only supported
existing knowledge offood contamination in Nigeria.