Digestion rate of dietary starch affects systemic circulation of amino acids in weaned pig
Starch is the major energy-yielding ingredient in diet for mammals (including human), and its digestive behaviour will have major impacts on both energy balance and metabolic process of other nutritional ingredients in mammals. The present study was conducted to evaluate the in vitro and in vivo digestibility of dietary starch and its digestive behaviour on the systemic circulated amino acids in weaned pig. In Exp. 1, corn starch (CS), sticky rice starch (SRS) and resistant starch (RS) were hydrolyzed in an in vitro digestion model; the digestibility of each was measured at different incubation time. In Exp. 2, eighteen weanling pigs (BW = 7.04 ± 0.52 kg), surgically fitted with a catheter in jugular vein, were randomly assigned to three dietary treatment groups. Venous blood samples were taken for determining serum amino acids concentration on d 7. On d 8, all pigs were euthanized, digesta from 4 fragments of small intestine were collected for determination of in vivo digestibility of starch. Results showed the in vitro digestibility of dietary starch was gradually increased when the incubation time extended. SRS, hydrolyzed quickly (P < 0.05) than CS and RS, was almost completely hydrolyzed within 4 h. The hydrolysis rate of CS was kept in a slow and steady pace, more than 95.76 ％ of which was hydrolyzed within 6 h, that of RS was even slower (P < 0.05) than of CS. The in vivo digestibility of dietary starch in different segments of small intestine was significantly different. 81.90％ of SRS was digested in anterior jejunum, but not more than half of CS and RS were digested in the same segments of small intestine. The serum concentrations of nutritionally indispensable amino acids, proline and serine in the 3 groups were increased to a peak point within postprandial one and an half hour then decreased gradually, however, the time that serum concentrations of alanine, aspartate, glutamate and glycine in each group increased to a peak point was different. An interesting finding was the concentrations of most nutritionally indispensable amino acids and proline in SRS group were higher (P < 0.05) than in CS and RS group at 0930 and 1330h, respectively. Collectively, these findings indicated that the different digestion rates of dietary starches in small intestine may affect the postprandial systemic circulated amino acids levels thus affect the metabolic process of amino acids in body.
Starch Digestion rate Amino acid Pig
F.G.Yin Z.Z.Zhang J.Huang Y.L.Yin J.H.Gong
Key Laboratory for Agro-ecological Processes in Subtropical Region, Institute of SubtropicalAgricult Key Laboratory for Agro-ecological Processes in Subtropical Region, Institute of SubtropicalAgricult Key Laboratory for Agro-ecological Processes in Subtropical Region, Institute of SubtropicalAgricult Guelph Food Research Center, Agriculture and Agri-Food Canada, N1G 5C9 Guelph, Ontario, Canada
国际会议
4th International Symposium on Animal Nutrition,Health and Feed Additive(第四届动物营养、保健与饲料添加剂国际学术研讨会)
广州
英文
186-196
2009-07-04（万方平台首次上网日期，不代表论文的发表时间）