Influence of rumen escape starch on pancreatic exocrine secretion of goats.
The objective of the experiment was to evaluate the effect of rumen escape starch (RES), accomplished by altering dietary starch concentrations on pancreatic exocrine secretion of goats. Four goats (36.8 +/- 3.2 kg) with common bile duct re-entrant and duodenal catheters were used in a 4 x 4 Latin square. Goats were fed diets containing 20%, 30%, 40% and 50% starch. Periods consisted of 10 day adaptation followed by 3 day of sample collection. Juice was collected in 1-h fractions continuously for 72 h. Total juice secreted was recorded, and 3% sub samples were retained to form a composite sample. The remaining fluid was returned to the duodenum. Juice composite samples were analyzed for activities of alpha-amylase, trypsin, chymotrypsin and lipase. Secretion of pancreatic alpha-amylase was lower (p < 0.05) when comparing lambs fed 20% starch diet with 30%, 40% and 50% starch diets. Lipase secretion was greater (p < 0.05) in lambs fed 40% starch diet compared with the other diets. Total secretion of juice, trypsin and chymotrypin was not affected (p > 0.05) by dietary starch concentration. Rumen escape starch increased with increasing dietary starch concentration (p < 0.05). Regression analysis showed that increasing RES results in a quadratic increase (p < 0.05) in pancreatic alpha-amylase and lipase secretion, and the secretion of alpha-amylase and lipase is maximum when RES is 113 and 83 g/day respectively. These results suggest that optimal RES for pancreatic secretion of alpha-amylase and lipase is 80-110 g/day in adult goats.
Xu
M
M
College of Animal Science, Northwest A&F University, Shaanxi, Yangling 712100, P. R. China.
Du
S
S
Wang
J
J
Yu
Z P
ZP
Harmon
D L
DL
Yao
J H
JH
D000818:Animals; D002404:Catheterization / Q000662:veterinary; D002918:Chymotrypsin / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004386:Duodenum / Q000378:metabolism; D006041:Goats / Q000378:metabolism*; D008049:Lipase / Q000378:metabolism*; D008297:Male; D046790:Pancreas, Exocrine / Q000378:metabolism*; D011897:Random Allocation; D012417:Rumen / Q000378:metabolism*; D013213:Starch / Q000008:administration & dosage* / Q000378:metabolism*; D014357:Trypsin / Q000378:metabolism; D000516:alpha-Amylases / Q000378:metabolism
D013213:Starch; D008049:Lipase; D000516:alpha-Amylases; D002918:Chymotrypsin; D014357:Trypsin