Use of a formalin-treated, live Escherichia coli vaccine in the prevention of neonatal enteric colibacillosis in swine.

A field trial was conducted to evaluate the effectiveness of an Escherichia coli vaccine in prevention of neonatal enteric colibacillosis in swine. Sows (272 total) were allotted to control (151 sows) and vaccinated groups (121 sows). Sows in the vaccinated groups were given a single intramuscular injection of a formalin-treated, live E coli vaccine 10 to 20 days prior to farrowing. The effects of the vaccination were to: (1) reduce mortality from 2.14 to 0.93 (P less than 0.001) pigs per litter; (2) reduce number of pigs with diarrhea, from 7.28 to 3.12 (P less than 0.004) per litter; and (3) increase number of pigs weaned, from 7.62 to 8.2 (P less than 0.005) per litter. The advantages of vaccination were most apparent in the barns with less than adequate sanitation and ventilation.