Submitted to: Journal of Food Protection
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/17/2001
Publication Date: 8/9/2001
Citation: Smith, D., Blackford, M., Younts, S., Moxley, R., Gray, J.T., Hungerford, L., Milton, T., Klopfenstein, T. 2001. Ecological relationships between the prevalence of cattle shedding Escherichia coli O157:H7 and characteristics of the cattle or conditions of the feedlot pen. Journal of Food Protection. 64(12):1899-1903. Interpretive Summary: Escherichia coli bacteria serotype 0157:H7 has been associated with beef cattle and infection with 0157:H7 can cause severe illness and death in humans. Control of 0157:H7 in the cattle population has become a priority of the industry. This study was conducted to determine if there was a relationship between cattle shedding 0157:H7 and conditions of their pens. Feces was rectally collected from cattle from 29 pens from five Midwestern feedlots once between June and September and cultured for 0157:H7. The pen conditions were also recorded. E. coli 0157:H7 was recovered from 719 of 3,162 (23%) fecal samples. Shedding varied widely between feedlots. Muddy pen conditions were associated with a higher prevalence of shedding than non-muddy pens. These data suggest that 0157:H7 is common among cattle. Additionally, these data will assist in the development of prevention and control measures for the industry.
Technical Abstract: This study was design to describe the percentage of cattle shedding Escherichia coli O15:H7 in Midwestern U.S. feedlots and to discover relationships between the point prevalence of cattle shedding the organism and the characteristics of those cattle or the conditions of their pens. Cattle from 29 pens of five Midwestern feedlots were sampled once between June and September 1999. Feces were collected from the rectum of each animal in each pen. Concurrently, samples of water were collected the water tank, and partially consumed feed was collected from the feedbunk of each pen. Characteristics of the cattle and conditions of each pen might have affected the prevalence of cattle shedding E. coli O157:H7 were recorded. These factors included the number of cattle; the number of days on feed; and the average body weight, class, and sex of cattle. In addition, the temperature and pH of the tank water were determined, and the cleanliness of the tank water and the condition of the pen floor were subjectively assessed. The samples of feces, feed, and water were tested for the presence of E. coli O157:H7. E. coli O157:H7 was isolated from the feces of 719 of 3,162 cattle tested (23%), including at least one animal from each of the 29 pens. The percentage of cattle in a pen shedding E. coli O157:H7 did not differ between feedyards, but it did vary widely within feedyards. A higher prevalence of cattle shed E. coli O157:H7 from muddy pen conditions than cattle from pens in normal condition. The results of this study suggest that E. coli O157:H7 should be considered common of cattle shedding the organism.