[A field experiment using E. coli-K99 vaccine]

In a field experiment in which vaccine containing E. coli-K99 antigen were administered to approximately thirty per cent of the pregnant dairy cows in herds in which the calves were affected with scours, during the first five days of life (the other animals were treated with a placebo), following results were obtained: The colostrum of vaccinated cows contained significantly higher concentrations of immunoglobulins to E. coli-K99 than did that of controls (Table 1). From the start of the experiment, severe scouring disappeared in the calves of vaccinated cows, and from those of the controls. E. coli-K99 could no longer be isolated. Zoötechnical measures such as adequate supplementation colostrum, hygienic procedures, etc., probably played an important role in the disappearance of the problems of scouring in these herds.