SUMMARY

The muscle (meat) of a healthy animal is sterile. Contamination may be due to infection within

the animal or external contamination during slaughter and handling processes. High bacterial

load on carcasses may pose potential risk of meat contamination with Foodborne pathogens.

A cross sectional study was carried out to determine the bacterial load and isolate Salmonella

species from cattle carcasses slaughtered at Kano abattoir. An eighty cattle carcass was sampled

between December 2012 to April, and 2013. Swabs were collected from four positions (neck,

shoulder, brisket, and rump) on each carcass. The laboratory procedure was carried out using

ISO 6579:2002. Conventional biochemical test as well as MicrobactTM 12E was used for

bacterial identification. Data was analyzed using Epi info 7 and Microsoft Excel, 2007.

Out of the examined 80 carcasses 41 (51.3%) were from male and 39 (48.8%) from female

cattle carcasses. Bacteria but only 50 (62.5%) carcasses sampled yielded growth on Salmonella-

Shigella agar contaminated Seventy-nine (98.8%) cattle carcasses sampled. The average colony

count ranges from 3.8×105 to 2.3×106. The mean log cfu/ cm2 were 4.4±0.77. The study reveals

that only 15 (19%) of the total carcasses sampled are contaminated at satisfactory level of less

than 5 colonies per plate on average. Among the 50 carcasses sampled that yielded growth on

Salmonella-Shigella agar only 1 (1.25%) was identified by MicrobactTM 12E as Salmonella

Arizonae with the percentage probability of 76.4%. Other pathogenic bacteria include;

Citrobacter freundii (4.3%), Klebseilla oxytoca (25.5%), Proteus vulgaris (66.0%) and

Providentia rettgeri 4.3%.

The mean log cfu/cm2 from the findings of this study was within the marginal acceptable limit

(3.5-5.0 log cfu/cm2). The major sources of contamination are multiple contacts with

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contaminated tools and operators‟ hands. Other possible source of contaminants, may due to the

unhygienic manner of handling meat in abattoirs, the environment upon which the meat is

slaughtered as well the water used in the processing of the meat. The prevalence of Salmonella

species was (1.25%).

In conclusion, the result of this work reflects poor conditions of carcasses slaughtering and

handling, and inadequate hygienic practices at Kano abattoir. Microbial load found in this study

shows to be above the satisfactory limit of carcass contamination. Salmonella was isolated in this

study and four other bacteria were isolated and identified.

It is therefore, recommended that thorough and adequate training on sustainable sanitary and

hygiene practice should be given to the abattoir workers periodically as well as implementing

strict meat inspection procedures.

Key             words:             Bacterial             load,             cattle,             carcass,             Salmonella

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CHAPTER ONE - INTRODUCTION

1.1 Background Information

Food-borne pathogens are the leading cause of disease and death in developing countries costing

lots of money in medical care and social costs. 1 Changes in eating habits, mass catering,

complex and lengthy food supply procedures with increased international movement and poor

hygiene practices are major contributing factors. 2 Contaminated raw meat is one of the main

sources of food-borne illnesses. 3, 4 The risk of the transmission of zoonotic infections is also

associated with contaminated meat.

Meat is considered an important source of proteins, essential amino acids, B complex vitamins

and minerals. Due to this rich composition, it offers a highly favorable environment for the

growth of pathogenic bacteria. The microbiological contamination of carcasses occurs mainly

during processing and manipulation; such as skinning, evisceration, storage and distribution at

slaughterhouses and retail establishments. 5, 6 Epidemiological reports suggest that meat product

is one of the major causes of diarrheal illness which account for 36% of mortality cases in

Nigeria. 137