Numbers of Campylobacter coli A11 (a) and phages (b) in faeces from broilers orally administered phage by food or by oral gavage. Forty-five, day-old chicks were inoculated with Campylobacter coli A11. One week later the birds were randomly assigned to one of three groups, a non-treated group and two treated groups: a group receiving the phage cocktail by oral gavage; and a group receiving the phage cocktail in feed. Birds were inoculated with antacid only, antacid containing 1 × 106pfu phage cocktail or antacid followed by feeding with the phage cocktail laced with 1.5 × 107pfu, respectively. Faecal samples were collected from all birds at intervals and Campylobacter and phages enumerated. Error bars represent the standard error of the mean. At 1 dpa, 2 dpa, 4 dpa and 7 dpa there is a significant difference between control and infected groups at P < 0.05.