The details of the results of treatment with terramycin are presented in table At 3rd day of treatment in 50 % of piglets diarrhoea had stopped and on 4th day none had any more diarrhoeic faeces. The microscopical examination of faeces 48 hours after the end of medication revealed the total absence of B. coli in 14 animals. The remaining 6 had still low level of infection (+ instead of +++).