Activities of enzymes of the pancreas, and the lumen and mucosa of the small intestine in growing broiler cockerels fed on tannin-containing diets.
Diets containing vegetable tannins, predominantly hydrolysable gallotannins, at levels of 13.5, 25 and 50 g/kg were fed to growing broiler cockerels to examine their effect on enzymes in the pancreas, the intestinal lumen and the intestinal mucosa. Pancreas weight per unit live weight showed a significant (P less than 0.05) increase with increasing level of dietary tannin while that of the liver remained unaffected. Trypsin (EC 3.4.21.4) and alpha-amylase (EC 3.2.1.1) activities in the pancreas of birds fed at the highest level of tannins were more than double those from birds fed on a tannin-free control diet. In the intestinal lumen inhibition of trypsin activity increased with increasing level of dietary tannin; alpha-amylase activity was inhibited at intermediate tannin levels but was restored at the highest level. Dipeptidase (EC 3.4.13.11) and sucrose alpha-glucosidase (disaccharidase) (EC 3.2.1.48) in the intestinal mucosa were both inhibited by tannins. Growth of the birds and digestibility of nitrogen were adversely affected by the tannin-containing diets.
Ahmed
A E
AE
Department of Agricultural Biochemistry and Nutrition, University of Newcastle upon Tyne.
Smithard
R
R
Ellis
M
M
D000821:Animal Feed; D000818:Animals; D002645:Chickens / Q000254:growth & development / Q000378:metabolism*; D004150:Dipeptidases / Q000378:metabolism; D004186:Disaccharidases / Q000378:metabolism; D007413:Intestinal Mucosa / Q000201:enzymology*; D007421:Intestine, Small / Q000201:enzymology*; D008297:Male; D008871:Microvilli / Q000201:enzymology; D009584:Nitrogen / Q000378:metabolism; D009929:Organ Size; D010179:Pancreas / Q000033:anatomy & histology / Q000201:enzymology*; D013634:Tannins / Q000008:administration & dosage / Q000378:metabolism*; D014357:Trypsin / Q000378:metabolism; D000516:alpha-Amylases / Q000378:metabolism
D013634:Tannins; D004186:Disaccharidases; D000516:alpha-Amylases; D004150:Dipeptidases; D014357:Trypsin; D009584:Nitrogen