Isolation and characterisation of Listeria species from ruminants in Maiduguri north–eastern Nigeria

Abstract

A cross sectional study was carried out to determine the prevalence of Listeria species in ruminants in Maiduguri. Three hundred faecal samples were randomly collected from ruminants at the Maiduguri central abattoir from January – March, 2011. One hundred faecal samples each were collected from cattle, sheep and goat at ante mortem by balloting comprising of fifty samples each from male and female animals. Forty (13%) of the three faecal samples were identified as positive Listeria species.  Out of the forty positive samples, 15(37.5%) were from cattle, 16(40%) from sheep and 9(22.5%) were from goats, the difference was not statistically significant (P > 0.05). The sex distribution of the animals positive for Listeria species showed that 21(7%) of the positive samples were from males and 19 (6%) were from females. The sex specific prevalence in the animal species sampled was not statistically significant (P > 0.05). Biochemical characterisation of the Listeria isolates showed Listeria monocytogenes 4(10%), Listeria innocua 17 (42.5%), Listeria ivanovii 12 (30%), Listeria seeligeri4(10%), and Listeria welshimeri 3(7.5%). This study affirms the isolation of Listeria species in the faeces of ruminants brought for slaughter at the abattoir which could serve as a source of contamination of meat meant for human consumption.

Keywords: Listeria species, ruminants, north-eastern Nigeria

Afr. J. Biotechnol. Vol. 12 No. 50