title: Growth and development of the digestive organs and some enzymes in broiler chicks after hatching.
abstract: 1. Body weight and the weight of the digestive organs and activities of some digestive enzymes were determined from hatching to 23 d of age. 2. Relative daily growth rate peaked at 11 d of age (22% gain/d) and then decreased gradually. 3. The vitelline residue was decreased rapidly from 4.6 g at hatching to negligible values from 4 d of age. 4. Maximal allometric growth of the pancreas and small intestine was 4-fold and that of liver 2-fold greater than that of the body. 5. Activities (units/kg body weight) of the digestive enzymes measured in the pancreas and intestinal contents increased with age. In the pancreas maximal values were attained on day 8 for amylase and lipase and 11 for trypsin and chymotrypsin. In the small intestine maxima were attained on day 4 for lipase, 11 for trypsin and chymotrypsin and 17 for amylase. 6. The development of secretion of digestive enzymes in the post-hatched chick could be a limiting factor in digestion and subsequently in food intake and growth.
authors.affiliation: Agricultural Research Organization, Volcani Center, Bet Dagan, Israel.
authors.forename: Z
authors.initials: Z
authors.lastname: Nitsan
authors.forename: G
authors.initials: G
authors.lastname: Ben-Avraham
authors.forename: Z
authors.initials: Z
authors.lastname: Zoref
authors.forename: I
authors.initials: I
authors.lastname: Nir
mesh_terms: D000681:Amylases / Q000378:metabolism; D000818:Animals; D002645:Chickens / Q000254:growth & development* / Q000378:metabolism; D002918:Chymotrypsin / Q000378:metabolism; D004064:Digestive System / Q000201:enzymology / Q000254:growth & development*; D004435:Eating; D007421:Intestine, Small / Q000201:enzymology / Q000254:growth & development; D008049:Lipase / Q000378:metabolism; D008099:Liver / Q000737:chemistry / Q000254:growth & development; D008297:Male; D009929:Organ Size; D010179:Pancreas / Q000201:enzymology / Q000254:growth & development; D014357:Trypsin / Q000378:metabolism; D015430:Weight Gain
chemical_list: D008049:Lipase; D000681:Amylases; D002918:Chymotrypsin; D014357:Trypsin