Distribution of trypsin and α‐amylase activities in the duodenum of the domestic fowl

Synopsis Trypsin and α‐amylase activities were found in the chyme from each of four quarters of the duodenum from White Leghorn cockerels aged 14 to 16 weeks. The average trypsin activity in the chyme from the first three quarters was 45 per cent of that found in the fourth quarter; that for a‐amylase was 23 per cent. These differences are highly significant. Activities of each enzyme in the first three quarters did not differ significantly. Chromic oxide was not an adequate internal reference marker for use in this type of study. The findings are discussed in relation to the peristaltic activity of the fowl's duodenum and the role of the duodenum in the digestive process.