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Abstract
Milk can serve as a source of bacterial contamination. Being a suitable medium for different bacterial growth, improperly handled sheep milk improperly dealt with using contaminated utensils or dirty hands, can pose serious health hazards. Infectious diseases that occur due to pathogenic bacteria are the most common and widespread in areas where sheep milk is consumed. Some pathogenic bacteria in milk are capable of breaking of important milk components and their utilization, such as lactose, which can disturb the nutritional profile of milk. Disseminated through contaminated sheep milk, some of these pathogens can be life threatening. Therefore, the objective of the study was to assess the prevalence of bacterial contamination and associated factors in the milk collected from different sheep breeds. The five breeds of sheep (Ovis aries) were selected (Dumbi, Kochi, Kooka, Balochi and Mengali) from fifteen locations of Sindh and nine Locations of Balochistan, Pakistan. 2 ml of milk was collected in sterile plastic vials and kept at 2-3˚C during the main lactation period of ewes. The pH of sheep milk ranged from 5.32 to 6.70. Milk of Dumbi and Kochi was observed to be the most contaminated, whereas Mengali’s milk was observed to be the least contaminated. The isolated bacteria belonged to E. coli, Pseudomonas and Listeria species.
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