Coliform counts and Escherichia coli in raw commercial milk from dairy farmers in Kiambu District, Kenya

Abstract

The rate of contamination with coliforms and incidence of Escherichia coli (E. coli) in raw milk supplied by farmers to dairy cooperative societies for marketing was investigated. About forty two (42.2%) percent of the milk samples from farmers cans and 10.3% of samples from cooperative cans were found to be free of coliforms, while 89.5% of the samples from farmers cans and 50% samples from cooperative cans could be considered to be of good quality with no more than 50,000 coliforms/ml of milk. Forty two E. coli strains were isolated from milk samples, five of which were found to be enteropathogenic, while none was found to be of serogroup O157. The results indicated that a good number of farmers draw milk under satisfactory conditions, but awareness campaigns on clean milking, milk handling and storage practices should be stepped up in order to reach farmers who may not be informed. Again the study showed that raw milk can get contaminated with enteropathogenic strains of E. coli that can pose a potential risk to humans, thus calling for extra care when preparing milk and milk products that are to be consumed by human beings.