Two men developed Campylobacter jejuni infections after castrating lambs during a multiday event to castrate and dock the tails of 1,600 lambs. Both men had used their teeth to castrate the lambs and were the only persons at the event who had used this castration method. A few lambs exhibited mild diarrheal illness. Campylobacter jejuni was isolated from two lambs; one isolate had a pulsed field gel electrophoresis(PFGE) pattern indistinguishable from the two human isolates