BACTERIAL LOAD AND ISOLATION OF SALMONELLA SPECIES FROM CATTLE CARCASSES AT KANO ABATTOIR

(A CASE STUDY OF KANO STATE, NIGERIA)

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Author

Presented To

Department of Medicine

ABSTRACT
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 xv 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.