Vaccines administered by Cargill Meat Solutions to 85,000 head of cattle in the Fort Morgan, CO area this past May through August are showing potential promise for reducing E. coli O157:H7 in beef.

Cargill’s large-scale tests of E coli O157:H7 vaccines, announced last January, were successful enough that the meat giant rolled out some of the results at a recent meeting of the food and feed safety committee of the U.S. Animal Health Association in Minneapolis.

“While we are pleased with the preliminary results, we are also eager to see completed analytical work currently underway by independent researchers at Kansas State and Texas Tech universities, the U.S. Department of Agriculture Meat Animal Research Center and the Beef Check-off, which should be available early in 2011,” said Dan Schaefer, Cargill’s assistant vice president for beef research and development.

Schaefer said Cargill saw a favorable immune system response to the vaccine just as it had hoped with no adverse reaction from the cattle.  A second round of trials is planned for summer 2011 at a beef processing facility in the Midwest, which is supplied by mid-sized feedlots.

“We are determining the best way to proceed with this science-based, evolutionary process, which we hope will lead to validating the potential value of vaccine as another food safety tool for beef production,” Schaefer added.

Cargill figures the effectiveness of the vaccine might be influenced by weather, geography, seasonality, animal and herd care management, vaccine doses, and other factors.

The control group also had a low level of E. coil O157:H7 while the vaccinated cattle were being processed at Cargill’s Fort Morgan processing plant.  Independent researchers are interpreting the data.

Researchers are trying to better understand the meaning and value of the reduction in E. coli O157:H7 in beef from vaccinated animals, compared with beef from those that did not receive the vaccine, according to Cargill. 

The Minneapolis-based company said the vaccine trial involving the 85,000 head of Colorado cattle was the first pre-harvest intervention trial completed that monitored activity from the time of the vaccination through measures in the meat.

“The low level of E. coli O157:H7 in the beef from control cattle is something we need to take into consideration when we analyze the data to determine the vaccine’s true impact and potential,” Schaefer continued.  “The scientist in me tells me much more research remains to be conducted before we can draw any meaningful conclusions about the long term efficacy of vaccine use to reduce any strain of bacteria potentially found in beef that could pose health risks to consumers.”

The 2010 vaccine trials, which cost Cargill $1 million, used an E. coli O157:H7 vaccine developed by Epitopix LLC, based in Wilmar, MN.  Cattle from 10 feedlots supplying Cargill’s Fort Morgan plant were vaccinated with either one or two doses.

The 145-year-old Cargill is one of the top three beef producers in the U.S.  The privately held company employs 131,000 people in 66 countries.