What if reduction of E.coli O157 could start at the source? E. Coli Bacterial Extract vaccine1 with SRP® technology, from Pfizer Animal Health, is the first and only vaccine approved by the USDA to reduce the amount of Escherichia coli (E. coli) O157 pathogens in the intestines of cattle. Call 800-733-5500 to learn more. 1 This product is conditionally licensed. Efficacy and potency test studies are in progress. All brands are the property of their respective owners. ©2010 Pfizer Inc. All rights reserved. SRP10012