ARS | Publication request: RISK FACTORS FOR FECAL SHEDDING OF SALMONELLA IN 91 US DAIRY HERDS IN 1996

Submitted to: Preventive Veterinary Medicine
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: September 16, 1999
Publication Date: January 10, 2000
Citation: Kabagambe, E.K., Wells, S.J., Garber, L.P., Salman, M.D., Wagner, P.J., Cray, P.J. 2000. Risk factors for fecal shedding of salmonella in 91 us dairy herds in 1996. Preventive Veterinary Medicine. Vol. 43. P. 177-194.

Interpretive Summary: Salmonella infection in dairy cattle results in lost production and income to producers. Additionally, Salmonella may occur in the milk or persist through to processing and may be transmitted to humans through food. One means of controlling Salmonella on the farm is to determine which factors affect persistence of Salmonella. We conducted a study on the management practices implemented in the dairy industry and analyzed the data to look for associations with fecal shedding of Salmonella. Herd size, region of the country, use of flush water systems, and feeding brewers products to lactating cows were identified as the most important risk factors. Intervention at the farm level will aid in reducing or eliminating numbers of Salmonella and provide for a more safe and wholesome product.

Technical Abstract: In 1996, data on management practices used on US dairy operations were collected and analyzed for association with fecal shedding of Salmonella by dairy cows. A total of 4,299 fecal samples from 91 herds was cultured for Salmonella isolation. Herd-size (adjusted odds ration (OR) =5.8, 95% CI 1.1, 31.3), region (OR = 5.7, CI 1.4, 23.5), use of flush water systems (OR = 3.5, CI 0.9, 14.7), and feeding brewers products to lactating cows (OR = 3.4, CI 0.9, 12.9) were identified as the most important predictive risk factors. The population attributable risk (PARs) for herd-size region, flush water system, and feeding brewers' products to lactating cows were 0.76, 0.46, 0.37, and 0.42, respectively. The estimated PAR for all four risk factors combined was 0.95. The effects of these factors need to be more-closely evaluated in more-controlled studies, in order to develop intervention programs that reduce Salmonella shedding.