Open Access
Research (Published online: 05-09-2018)
3. Prevalence, toxigenic potential and antimicrobial susceptibility profile of Staphylococcus isolated from ready-to-eat meats
Chinwe E. Okoli, Emmanuel Okechukwu Njoga, Simon I. Enem, Enid E. Godwin, John A. Nwanta and Kennedy F. Chah
Veterinary World, 11(9): 1214-1221

Chinwe E. Okoli: Department of Veterinary Public Health and Preventive Medicine, University of Abuja, Nigeria.
Emmanuel Okechukwu Njoga: Department of Veterinary Public Health and Preventive Medicine, University of Nigeria, Nsukka, Enugu State, Nigeria.
Simon I. Enem: Department of Veterinary Public Health and Preventive Medicine, University of Abuja, Nigeria.
Enid E. Godwin: Department of Veterinary Public Health and Preventive Medicine, University of Abuja, Nigeria.
John A. Nwanta: Department of Veterinary Public Health and Preventive Medicine, University of Nigeria, Nsukka, Enugu State, Nigeria.
Kennedy F. Chah: Department of Veterinary Pathology and Microbiology, University of Nigeria, Nsukka, Enugu State, Nigeria.

doi: 10.14202/vetworld.2018.1214-1221

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Article history: Received: 07-02-2018, Accepted: 19-07-2018, Published online: 05-09-2018

Corresponding author: Emmanuel Okechukwu Njoga


Citation: Okoli CE, Njoga EO, Enem SI, Godwin EE, Nwanta JA, Chah KF (2018) Prevalence, toxigenic potential and antimicrobial susceptibility profile of Staphylococcus isolated from ready-to-eat meats, Veterinary World, 11(9): 1214-1221.

Aim: An epidemiological surveillance for Staphylococci contamination of ready-to-eat (RTE) meats from Enugu State, Nigeria, was carried out to determine the prevalence, species distribution, toxigenic potential and antimicrobial susceptibility profile of the organisms and hence the microbiological and toxicological safety of the meats.

Materials and Methods: Isolation and phenotypic Staphylococcus detection were done according to standard microbiological methods. Phenotypic resistance to 17 commonly used antimicrobial agents was determined by disc diffusion method. Molecular characterization of the isolates to species level and detection of selected toxigenic and antimicrobial-resistance genes were done by PCR methods.

Results: Twenty-four (9.4%) of the 255 meat samples investigated were contaminated with Staphylococcus species. Twenty-four Staphylococcus isolates belonging to six species of coagulase-negative Staphylococcus (CoNS) were identified. Four (16.7%) isolates harbored genes coding for exfoliative toxin-A. Ten (41.7%) isolates were multidrug resistant, while mecA, tetK, mphC, ermT and ermC were the antimicrobial-resistance genes detected in the isolates. Meat samples sourced from motor parks (16.7%) and open markets (8.5%) were the most contaminated.

Conclusion: 9.4% of RTE meats sampled were contaminated with toxigenic and multidrug resistance CoNS. Beef was the most contaminated RTE meat type and harbored all the toxigenic and most of the antibiotic-resistant genes detected. Meat samples from motor parks had the highest staphylococcal contamination (16.7%), while those from mechanic village had the least (2.4%). Majority (79.2%) of the isolates were not susceptible to fusidic acid but none exhibited antimicrobial-resistance to chloramphenicol, ciprofloxacin, linezolid or teicoplanin. Food safety authorities in the study area should work proactively to massively improve the hygienic practices of meat vendors; in order to limit staphylococcal contamination of RTE meats and the associated public health problems.

Keywords: antibiotic resistance, food safety, Nigeria, polymerase chain reaction, ready-to-eat meats, Staphylococcus.


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