Bacteria belonging to the family Enterobacteriaceae enter the animal feed chain as normal contaminants of raw materials used in the manufacture of animal feeds. The family Enterobacteriaceae encompasses 30 established genera, including Salmonella spp, Escherichia spp, Shigella spp and Yersinia spp. Many of the genera exhibit pathogenicity towards man, animals, insects and plants and many of the pathogenic forms produce toxins. A number of the genera in this family occur regularly in association with animals; they are found as indigenous members of the gut microflora where they may either produce no harmful effects, or are capable of causing disease in both endothermic and ectothermic animals. There is a recognised association between the risk of isolation of salmonella and degree of Enterobacteriaceae contamination (Veldman et al. 1995). This has led to the consideration of recording Enterobacteriaceae contamination levels in feed stuffs as an indicator of feed hygiene and potential limits to the degree of contamination being set by the major retailers. This paper sets out data gathered from the routine analysis of feed raw materials examined for Enterobacteriaceae contamination.