A Study on the Optimal Amino Acid Pattern at the Proximal Duodenum in Growing Sheep |
Hongrong Wang, Dexun Lu |
|
|
|
Abstract |
Nine crossbred castrated lambs fitted with rumen and duodenum cannula and fed a diet of hay and concentrate formulated with ground corn and soybean meal as main ingredients were used to assess the duodenal ideal amino acid pattern. Three synthetic amino acid mixtures with different profile of essential amino acids were duodenally infused in order to get three different amino acid patterns flowing into the duodenum. The mixtures were designed to have similar amino acid profile as rumen microbial protein (Pm), casein (Pc) and modified muscle amino acid (Pmm). Results showed a lower urine nitrogen excretion (p=0.05), a higher nitrogen retention (p=0.04) and bodyweight gain with treatment Pmm. The modified muscle amino acid pattern also promoted a lower ratio of Gly to other amino acids in plasma (Gly/OAA) and a higher RNA and RNA/DNA concentration in the liver of the sheep. Meanwhile, the urea concentration in plasma was reduced and the insulin concentration was increased with Pmm treatment. No differences in glucose and growth hormone concentration in plasma were found among three treatments. All results obtained indicate that the modified muscle amino acid pattern (Lys 100%, Met+Cys 39%, Thr 76%, His 41%, Arg 72%, Leu 158%, Ile 81%, Val 105%, Phe 81% and Trp 13%) was the best for growing sheep. |
Keywords:
Amino Acids; Duodenum; Growing Sheep |
|