Prevalence of microbial contaminants in dairy concentrates in Nairobi peri-urban area

Abstract

The presence of harmful pathogens and toxins in animal feeds is an important aspect of feed quality and has implications to animal and human health as well as the environment. To assess the distribution and levels of these microbiological feed contaminants in dairy cattle feeds, 100 dairy farmers were randomly selected in Nairobi area and the range of feed concentrates frequently used on the farms sampled. Using novel ELISA kits, the feed ingredients were analysed for aflatoxins, Salmonella spp ., E. coli and total microbial counts. Preliminary results indicate that over 50% of dairy concentrates sampled were contaminated with aflatoxins, Salmonella spp . and E. coli . The most susceptible concentrates included cotton seed meal, maize germ, commercial dairy meal and home made rations. Although the exact source of contamination was not ascertained, storage conditions in majority of the farms were characterised by lack of adequate ventilation and dampness. It is known that frequency and levels of contamination are related to weather conditions as well as to agronomic, storage and handling practices. The study suggests that there is need to identify sources of contaminants for dairy concentrates and their residues in dairy products.