Siderophore-receptor and porin-based (SRP) Escherichia coli vaccine technology
functions by starving the E. coli organism via competitive exclusion for proteins that
scavenge iron, an essential nutrient for E. coli viability. Vaccination with SRP E. coli
technology decreased the prevalence of E. coli O157:H7 in artificially inoculated cattle
and in cattle naturally shedding the organism. Examination of the effects that SRP E.
coli vaccines exert on performance parameters has yet to be attempted in a commercial
setting.
The use of SRP E. coli vaccine technology effectively decreases the prevalence of E. coli
O157:H7 in feeder cattle and may improve beef safety; however, the vaccine’s effects on
the economics of cattle feeding are unknown. Therefore, the objective of our study was
to assess the effects of vaccinating cattle three times with an SRP E. coli vaccine verses a
placebo on performance, health, and carcass characteristics of cattle fed in commercial
feedlots.