Project Number: 6202-32000-018-10
Project Type: Trust

Start Date: Apr 01, 2004
End Date: Apr 30, 2005

Objective:
To isolate and characterize several E. coli O157:H7 infecting bacteriophage from feedlot manure and test their efficacy as a preharvest intervention strategy to reduce E. coli O157:H7 in ruminants.

Approach:
Fecal samples from cattle in TX and OK will be screened for isolation of bacteriophage against E. coli O157:H7. Following a basic evaluation, the most potent phages identified will be utilized to develop the optimal combination of phages for a cocktail. 1) Sheep will be inoculated with E. coli O157:H7, Sheep will be in 2 groups, control and phage-treated. After 48 h, sheep will receive a cocktail of phage. Sheep will be euthanized 72 h after phage treatment. Intestinal samples from the rumen, cecum and rectum, will be quantified. 2) Sheep will be inoculated with E. coli O157:H7 in 4 groups. After 48 h, infected sheep will receive a phage cocktail of one of three MOI levels. Sheep will be euthanized after 72 h and necropsied. 3) Sheep will be inoculated with E. coli O157:H7 in 2 groups, control and phage-treated. After 48 h, infected sheep will receive a phage cocktail at the optimal MOI. Sheep will be euthanized at 72, 96, 120, and 144 h after phage and necropsied.

Project Team

Callaway, Todd

Related National Programs

Food Safety, (animal and plant products) (108)