Submitted to: World Health Organization
Publication Type: Proceedings
Publication Acceptance Date: August 15, 1999
Publication Date: N/A
Interpretive Summary: Studies were done in Arkansas, Alabama and Georgia to determine efficacy of MSC(TM) to reduce salmonellae in broilers. Chicks were sprayed with an MSC(TM) solution using a spray vaccination cabinet in the hatchery and also received MSC(TM) in the first drinking water at the growing house. MSC(TM) treated carcasses sampled after final washer and before the final chiller had significantly (p=.05) less salmonellae (12 of 180) than untreated control birds (23 of 180). After chill, salmonellae were detected on 9 of 180 untreated control chickens compared to 0 of 180 MSC(TM) treated chickens significant difference, (p,.01). These data confirm a significant reduction in salmonellae found on broiler carcases treated with MSC. Using similar techniques, a mucosal competitive exclusion (MCES) was produced from the cecum of a 6 week old pig. Suckling pigs were inoculated with 5 ml MCES by oral gavage 6 hours post farrowing (PF) and again at 24 h PF. Challenge was 10(3) CFU salmonellae choleraesuis at 48 h PF by intranasal instillation. All pigs were necropsied on day 7 PF and presence of salmonellae was determined in both qualitative (10 tissues) and quantitative (2 tissues) samples. From pigs in the control group, 79% of the intestinal tissues were salmonellae positive whereas only 28% of the MCES intestinal tissues were salmonellae positive. MCES may be a useful approach for control of salmonellae in pigs.
Technical Abstract: Eggshell fragments, paper pads from chick boxes and fluff samples were obtained from three commercial primary breeder hatcheries and analyzed for the presence and level of salmonellae with identical laboratory methods in 1991 and 1998. Overall, 29 of 180 samples (16.1%) from the three hatcheries in 1998 were contaminated with salmonellae, whereas in 1991, 11.1% of the overall samples were found to be salmonellae positive. Salmonellae organisms were detected in 1.7%, 1.7% and 45% of the eggshell fragments, fluff and paper pad samples, respectively in 1998, whereas 15.2%, 4.5% and 12% of these type samples were salmonellae positive in 1991. From an enumeration standpoint, the salmonellae contamination in primary breeder hatcheries seems to have improved in the past seven years. In 1998, less than 4% of the positive samples had high levels of salmonellae whereas in 1991 64% of the positive samples had high numbers of salmonellae. Both primary broiler breeder and boriler hatcheries present critical control points in the prevention of salmonellae contamination during commercial poultry production. The cycle of salmonellae contamination will not likely be broken until contamination at these critical points is dramatically reduced or eliminated.