Abstract
1. Dietary effects on body weight and digestive enzyme activities of germfree (GF) chicks were compared with those in conventional (CV) chicks fed zein+lysine+tryptophan (ZA), zein (Z) or protein-free (PF) diet.
2. The GF chicks gained more weight on ZA, lost more weight on PF, and died sooner after food deprivation than the corresponding CV chicks.
3. The chicks in each environment lost weight almost equally on Z.
4. In contrast to rodents, no significant higher enzyme activity was found in GF chicks. The total activities per tissues of alkaline phosphatase in duodenum on ZA and in caecum on ZA, Z and PF of CV chicks were higher than those of GF ones. The total sucrase activities in duodenum of CV chicks on ZA were higher than those of GF ones. The total leucine p-nitroanilidase activities in duodenum and jejunum of CV chicks on ZA were higher than those of GF ones.
5. Enzyme activity per mg DNA varied with diets and environments. Alkaline phosphatase activities of CV chicks were higher than those of GF ones. Sucrase activities in duodenum on ZA and in caecum of CV chicks on Z and PF were lower than those of GF ones. Leucine p-nitroanilidase activities in caecum of CV chicks on ZA and Z were also lower than those of GF ones.
