不同酪蛋白添加水平对湖羊肠系膜排流组织、门静脉排流组织中游离氨基酸和肽结合氨基酸净流量的影响

Effects of Dietary Casein Supplement Levels on Net Flux of Free Amino Acids and Peptide-bound Amino Acids in Mesenteric-drained Viscera and Portal-drained Viscera in Hu Sheep

本试验旨在研究饲粮不同酪蛋白添加水平对湖羊血浆中游离氨基酸(FAA)和肽结合氨基酸(PAA)释放量及肠系膜排流组织(MDV)、门静脉排流组织(PDV)净流量的影响。选用3只体况良好的湖羊,安装肠系膜静脉、门静脉和颈动脉插管。采用4×3不完全拉丁方试验设计,试验羊分别饲喂4种不同酪蛋白添加水平(A:0、B:3.0%、C:6.0%、D:9.0%)的饲粮。结果显示,湖羊血浆氨基酸浓度随着饲粮酪蛋白添加水平的升高而升高。MDV的FAA净流量以D组最高,且显著高于A组(P<0.05);PAA净流量则是C组最高,且显著高于A、B组(P<0.05)。PDV的FAA和PAA净流量都是C组最高,且显著或极显著高于A、B组(P<0.05或P<0.01)。结果提示,在一定范围内,饲粮蛋白质水平影响湖羊MDV和PDV中FAA和PAA的净流量。

The objective of this experiment was to investigate the effects of dietary casein supplement levels on the release of free amino acids（FAA） and peptide-bound amino acids（PAA） in plasma as well as the net flux in mesenteric-drained viscera（MDV） and portal-drained viscera（PDV） in Hu sheep.A 4×3 incomplete Latin square design was applied in this experiment.Three Hu sheep,which were fitted with portal vein,jugular vein and carotid artery catheters,were fed four diets containing different levels of casein as treatments： 0（A）,3.0%（B）,6.0%（C） and 9.0%（D）,respectively.The results showed that the concentration of amino acids in plasma increased in accordance with the increment of dietary protein levels.The net flux of FAA in MDV in treatment D was significantly greater than that in treatment A（P0.05）,and the net flux of PAA in MDV in treatment C was significantly greater than that in either treatment A or B（P0.05）.The highest net flux of FAA or PAA in PDV was observed in treatment C,which was significantly higher than that in either treatment A or B（P0.05 or P0.01）.These data imply that in certain extent,the net flux of FAA and PAA in either MDV or PDV of Hu sheep can be affected by dietary protein levels.