A cross-sectional study on prevalence and antibiotic susceptibility of E. coli isolated from raw meat samples was conducted in Kwata and Amansea abattoirs. A total of 24 meat samples collected from two abattoirs were cultured for detection of E. coli. Biochemical test was carried out on the isolated pure colonies, which were then tested for antimicrobial susceptibility. Comparison on the prevalence of the bacteria was made in relation to source (Kwata and Amansea abattoirs) and site (neck region, fore limb, hind limbs and lower back areas) of meat sample collection. The investigation revealed a 70.83% overall prevalence of E. coli in the meat samples. The neck region was found to be the highly contaminated site followed by lower back area, Fore limbs and Hind limbs, respectively. All the E. coli isolates were found susceptible to Augumentin, Ciprofloxacin, Gentamicin, Septrin and Ampicillin. This study evidenced a considerable presence of E. coli in cattle meat slaughtered in abattoirs in Awka city probably due to the poor sanitary conditions during processing. It also demonstrated the sensitivity of most E.coli isolates to antibiotics which may be of potential public health importance.
The term meat, refers to mammalian flesh consumed as food. Hence, raw meat refers to uncooked muscle tissue of animals that is used for food. Recently however, meat has been broadly defined to include poultry, shellfish, fish, frogs and alligators. Cattle and goat are very popular sources of beef and chevon respectively all over the world, Nigeria inclusive and Awka in particular. Meat and meat products have increasingly become part of daily human diet because of its rich and nutritive composition. Beef and chevon have been reported to contain high quality proteins, minerals, vitamins and fat. Meat is considered as 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 (Gill, 2001). Recent increase in the consumption of meat and its products arises from reasons including high protein contents, vitamins, minerals, lipids and savory sensation.
Ready-to-eat foods including red meats have been found to serve as carriers for several bacterial pathogens and food borne outbreaks that have been associated with the consumption of contaminated foods. A number of studies have reported outbreak of infections due to consumption of contaminated food and poor hygiene and in most of the cases, data are loosely based on laboratory isolates which do not reflect the actual ratio of food-borne infections. During slaughtering process the meat is exposed to many sources of Bacillus cereus contamination. The incidence of Bacillus cereus is higher in cooked and processed (ground beef) meat than in raw meat samples. Microbial contamination of raw meat results from processing, and starts during slaughter, when the carcass becomes contaminated with microorganisms residing on external surfaces, the gastrointestinal tract and lymph nodes of the animal, and in the plant environment. Furthermore, certain processing steps increase contamination by spreading the existing contaminants attached to the fresh meat surface to its entire mass or by introducing additional contaminants. For example, meat chopping or grinding results in greater microbial loads because of larger areas of exposed surface, more readily available water and nutrients, additional processing time, and contact with more sources of contamination such as equipment.Meat products are perishable and unless processed, packaged, distributed and stored appropriately can spoil in relatively short time (Sofos, 2005). Raw retail meats have been identified as potential vehicles for transmitting food-borne diseases, and hence the need for increasing implementation of hazard analysis of critical control point (HACCP) and food safety education efforts (Zhao et al.,2001). Sources of bacterial contamination of meat are hide, hooves, soil, intestinal contents, air, water supply, knives, cleavers, saws, hooks, floors and workers (Haines, 2006, Empey and Scott, 2008). Slaughtering of livestock continues to increase as a result of the increase in demand for meat and its products. The highly nutritious nature of meat provides a suitable environment for the growth of pathogenic, nonpathogenic as well as spoilage organisms. Its high consumption rate and popularity hence, makes contamination and its consequences an issue of concern, since raw meat and meat products have been identified as important vehicles of foodborne illnesses and implicated in food poisoning outbreaks. Diseases are spread through meat and meat products to humans by direct contact and ingestion of the finished product.
Escherichia coli (E. coli) are a group of bacteria that are part of the intestinal micro-flora of healthy animals and humans. However, certain serogroups, including . coli O157, can carry genes that allow them to produce toxins known as verotoxins or Shiga-like toxins. Vero toxigenic E. coli (VTEC) are not pathogenic to ruminants, but they cause serious diseases in humans worldwide, including diarrhea, hemorrhagic colitis, hemolytic-uremic syndrome, and sometimes death (Akinro et al., 2006). Consumption of contaminated raw and undercooked meat is the most common means of transmission to humans. Domestic ruminants, including goats, are natural reservoirs for E. coli O157; therefore they play a significant role in the epidemiology of human infections (Wenger and Meng, 2011). The pathogen is carried in the intestinal tract and excreted in the feces. During slaughter, the pathogen may be present on the skin or in the feces of the animal, and may get transferred to the carcass during evisceration or skin removal. Therefore, poor slaughter techniques, particularly poor hygienic practices during slaughter greatly increase the risk of meat contamination with E. coli O157. The risk of meat contamination also depends on the E .coli O157 carriage status of the slaughter animals. Therefore, assessment of slaughter hygiene and the carriage status of the pre-slaughter animal population are essential in determining the risk of exposure of meat consumers to E. coli O157.
The state of health of animals prior to slaughtering and the prevailing circumstances in the slaughter house can contribute to the quality of meat from such animals (Jespen, 2003). Reports have indicated that slaughtering of animals in rural communities within Nigeria particularly Awka is usually done under unhygienic conditions. In most cases, potable water is unavailable, leaving butchers with unhealthy water sources for use. These aforementioned reasons in addition to high ambient temperature, humidity and poor handling practices dispose raw meat to deterioration and contamination. Other sources such as animal skin, hide and feet, fecal material and the hands, clothing and equipment of slaughter men have been identified as routes of contamination (Abdullahi et al., 2006).
Additionally, antimicrobial resistance among enteric bacteria is an increasing global public health concern. The widespread administration of antimicrobials promotes the selection of antimicrobial resistant strains, which complicates the treatment of bacterial infections. Furthermore, antimicrobial resistance also has negative effects on animal health and the environment as per the One Health concept which highlights the interconnection of human, animal, and environmental health. Livestock in particular, are often considered as sources of antimicrobial resistance in industrialized countries, where antimicrobials are commonly used to improve productivity (Wenger and Meng, 2011).
The lack of surveillance of food-borne pathogens, poor hygienic conditions and sub-standard slaughter practices in the abattoirs, and the widespread cultural practice of raw meat consumption, are all major factors contributing to the high risk of exposure of Awka inhabitance to food-borne pathogens such as VTEC. In spite of the high risk of exposure to VTEC, there is no surveillance for this pathogen and very little is known about the carriage rate of E. coli O157 in different livestock populations. Also, more information is needed on antimicrobial resistance patterns in developing countries like Nigeria, particularly Awka where both veterinary and medical drugs are often misused, creating ideal conditions for the development of resistant strains (Barrow, 2012). To reduce this knowledge gap, this study was carried out to isolate Escherichia coli from raw meat samples in abattoirs in Awka city, to determine the extent of Escherichia coli contamination of raw meat samples from abattoirs in Awka city, to know the prevalence of Escherichia coli in raw meat from abattoirs in Awka city, to determine the antimicrobial susceptibility pattern of the isolates ,to identify risk factors contributing to Escherichia coli contamination of raw meat from abattoirs in Awka city and to recommend possible approaches to improving meat safety in Awka city.
Despite the foregoing and the high consumption rate of raw beef in Awka metropolis, there is little or no available information on their bacteriological quality. The dearth of information in this area has necessitated this research.
GENERAL OBJECTIVE OF THE STUDY
The overall objective of these study is to determine the prevalence and antimicrobial susceptibility of Escherichia coli from raw meat samples obtained from abattoirs in Awka city , Anambra state.
SPECIFIC OBJECTIVE OF THE STUDY
- To isolate Escherichia coli from raw meat samples in abattoirs in Awka city.
- To determine the extent of Escherichia coli contamination of raw meat samples from abattoirs in Awka city.
- To know the prevalence of Escherichia coli in raw meat from samples abattoirs in Awka city.
- To determine the antimicrobial susceptibility pattern of the isolates
- To identify risk factors contributing to Escherichia coli contamination of raw meat from abattoirs in Awka city.
- To recommend possible approaches to improving meat safety in Awka city.