SOURCES OF SALMONELLAE CONTAMINATION OF MEAT FOLLOWING APPROVED LIVESTOCK SLAUGHTERING PROCEDURES. II

Abstract

Samples were taken from 218 animals of 3 species slaughtered at 3 plants to determine the spread of bacterial contamination during slaughter. Salmonellae and Escherichia coli were cultured from swabs taken of the equipment during slaughter, from various carcass sites, and from fecal samples. The study indicated that some equipment contamination occurred during slaughter and that carcass washing did not remove contaminants but simply washed them lower on the carcass. Rumen/cecum samples were most effective for isolation of salmonellae from the gastrointestinal tract. The average level of salmonellae contamination of the carcass for all species was 10% and of the processed product, 2%. There were no salmonellae isolated from cattle carcasses. Isolation of the bung (rectum) with a plastic bag did not reduce contamination but sterilization of the bung dropper's knife between carcasses reduced the incidence by an average of greater than 50%. Salmonellae were isolated from boneless mutton but not from raw or cooked pork and beef products. Isolations from the hide were closely related with carcass contamination. Enrichment and non-enrichment media isolations of salmonellae were closely related.