Hydrolysis of phytic acid by intrinsic plant or supplemented microbial phytase (Aspergillus niger) in the stomach and small intestine of minipigs fitted with re-entrant cannulas.
Hydrolysis of phytate in the stomach and the small intestine as influenced by intrinsic plant (wheat) and supplemented microbial phytase (A. niger) were investigated with six minipigs (40-50 kg initial BW) fitted with re-entrant-cannulas in the duodenum, 30 cm posterior to the pylorus (animals 1, 4, 5, and 6) and ileocecal re-entrant cannulas, 5 cm prior the ileocecal junction (animals 1, 2, and 3), respectively. Dietary treatments were as follows: (1) diet 1, a corn-based diet (43 U Phytase/kg DM); (2) diet 2, diet 1 supplemented with microbial phytase (818 U/kg DM) and (3) diet 3, a wheat-based diet (1192 U/kg DM). At 0730 and 1930 per animal 350 g diet mixed with 1050 ml de-ionized water were fed. Digesta were collected continuously and completely during 12 h after feeding. Duodenal recovery of dry matter and total phosphorus were 100% in the period between two feedings, irrespective of dietary treatment. In animals fed the wheat-based diet, dry matter left the stomach faster (p < 0.05) during the first hour after feeding than in animals fed the corn-based diets (41.3 vs. 31.0 and 25.8% of intake, respectively). Supplemented microbial phytase did not affect ileal dry matter digestibility of the corn-based diet. In the first hour after feeding, phosphorus concentration of the duodenal digesta of animals fed corn-based diets with or without supplemented microbial phytase (5.86, 6.19 mg total P/g DM) exceeded the dietary level considerably (4.30 and 4.21 mg total P/g DM) indicating a higher solubility of corn than wheat phosphorus in the stomach. Apparent ileal P absorption was higher (p < 0.05) in the wheat-based diet (37.6%) and corn-based diet supplemented with microbial phytase (34.3%) than in the unsupplemented corn-based diet (17.6%).
Rapp
C
C
Institute of Animal Nutrition, Hohenheim University, Germany.
Lantzsch
H J
HJ
Drochner
W
W
D010832:6-Phytase / Q000008:administration & dosage / Q000378:metabolism*; D000821:Animal Feed; D000818:Animals; D001234:Aspergillus niger / Q000201:enzymology; D004063:Digestion; D005753:Gastric Mucosa / Q000378:metabolism*; D006868:Hydrolysis; D007421:Intestine, Small / Q000378:metabolism*; D008297:Male; D010758:Phosphorus / Q000378:metabolism*; D010833:Phytic Acid / Q000008:administration & dosage / Q000378:metabolism*; D013552:Swine; D013556:Swine, Miniature / Q000502:physiology*
D010758:Phosphorus; D010833:Phytic Acid; D010832:6-Phytase