British Journal of Dairy Sciences 1(1): 1-5, 2010 ISSN: 2044-2440 © Maxwell Scientific Organization, 2010 Submitted Date: April 06, 2010 Accepted Date: April 22, 2010 Published Date: June 20, 2010 Corresponding Author: M.D. Salihu, Department of Veterinary Public Health, Usmanu Danfodiyo University, P.M.B. 2254, Sokoto. Nigeria. 1 Study of Campylobacter in Raw Cow Milk in Sokoto State, Nigeria M.D. Salihu, A.U. Junaidu, A.A. Magaji and Z.M. Rabiu Department of Veterinary Public Health, Faculty of Veterinary Medicine, Usmanu Danfodiyo University, Sokoto, Nigeria Abstract: The study was conducted to establish the presence of Campylobacter species, determine its prevalence and assess some of the epidemiological variables such as breed and season in the distribution of Campylobacter species in raw cow milk in the state. During October, 2007 and September, 2008, a total of 146 raw milk samples were collected from lactating cows in selected dairy herds in the state. The samples were processed for Campylobacter isolations by inoculating in Preston Enrichment broth and incubated for 48h at 37ºC, and subsequently spread-plated on mCCDA incubated at 42ºC for 48 h microaerobically. The colonies were subjected to oxidase reaction, hippurate hydrolysis and sensitivity to nalidixic acid and cephalothin for identification. The identified isolates were biotyped using the new extended scheme of Lior. Only 7(4.8%) of the samples were positive and all the positive isolates were identified as C. jejuni and C. jejuni biotype I. The white Fulani breed of cattle had the highest contamination rate of 2(5.4%) and there was no association between the breed and Campylobacter contamination of milk (P 2 = 0.6997, p>0.005). More contamination rate of 3(6.1%) was observed during the dry hot season than other seasons, there was no association between Campylobacter contamination of milk and the seasons (P 2 = 0.3776, p>0.005). The isolation of C. jejuni from milk in this study is of serious public health concern as C. jejuni is the most common Campylobacter species implicated in human Campylobacteriosis worldwide. Key words: Campylobacter, cow, milk, prevalence, seasonal, Sokoto INTRODUCTION Food safety, and in particular safety of products of animal origin, is an increasingly important issue concerning human health. With increase in the consumption of products of animal origin the risk of foodborne diseases of humans also increases. The raw food movement, characterized by eating raw rather than cooked food has increased the awareness of consumption of raw food. One product that is commonly distributed in raw form is milk. Raw milk is a known vehicle and medium for pathogens such as E. coli, Mycobacterium bovis, Listeria monocytogenes and species of Campylobacter, Brucella and Salmonella (Leedom, 2006). Milk can become contaminated in many ways. For example, if the dairy cow has a mammary gland infection (mastitis) or a systemic infection, the pathogen can be passed to the milk. Milk can become contaminated by the faeces of the animals and the hand of the milker usually during hand milking procedure or by equipment used for milk collection and storage. Campylobacter species have been reported in many foods of animal origin (Altekruse et al., 1999). Surveys of raw agricultural products support epidemiologic evidence implicating poultry, meat, and raw milk as sources of human infection. Outbreaks of Campylobacteriosis are relatively rare (Pebody et al., 1997) and often associated with the consumption of unpasteurized milk (Evans et al., 1996) or untreated water (Palmer et al., 1983). Unpasturized milk is considered next to poultry as the most frequent cause of alimentary infections in people. Studies conducted have indicated that one out of five cases of Campylobacteriosis in people, where milk is the source of infection was caused by drinking unpasteurized milk. A prevalence of 6% of Campylobacter in unpasteurized milk on sale to the public has been demonstrated in Britain (Humphrey and Hart, 1988). In one study, 12% of raw milk samples from dairy farms in eastern Tennessee were contaminated with C. jejuni (Rohrbach et al., 1992). Raw milk is presumed to be contaminated by bovine faeces; however, direct contamination of milk as a consequence of mastitis also occurs (Hudson et al., 1984). This study was conducted to establish the presence of Campylobacter sp., determine its prevalence and assess some of the epidemiological variables such as breed and season in the distribution of Campylobacter sp. in raw cow milk in the state. MATERIALS AND METHODS The study was conducted in Sokoto state, Nigeria between October, 2007 and September, 2008.