Influence of infusing amino acids into the external pudendal artery on nutrient uptake in the mammary gland of dairy goats | 阴外动脉灌注氨基酸对奶山羊乳腺摄取乳成分前体物的影响

Китайский. 目的研究阴外动脉灌注不同平衡模式的氨基酸对奶山羊乳腺摄取乳成分前体物（milk components precursors，MCP）的影响规律。方法选用2―3周岁，体重、产奶量相近、安装有阴外动脉和腹部皮下静脉血插管的关中奶山羊3只，由阴外动脉灌注不同平衡模式的氨基酸，在灌注前后分别采集动静脉血浆，测定乳蛋白前体物（milk protein precursors，MPP）、乳脂前体物（milk fat precursors，MFP）和乳糖前体物（milk lactose precursors，MLP）的含量和乳腺对其的摄取。结果阴外动脉灌注不同平衡模式混合氨基酸改变了乳腺对MPP、MFP的摄取（P＜0.05），乳腺对MLP的摄取理想模式组和平衡模式组均高于不灌注组，但理想模式组与不灌注组差异不显著（P＞0.05），平衡模式组与不灌注组差异显著（P＜0.05）；不同氨基酸模式灌注组产奶量和乳成分明显高于对照组（P＜0.05）。结论阴外动脉中氨基酸的平衡改变了乳腺对乳成分前体物的摄取，有利于乳的合成。本试验条件下，阴外动脉中必需氨基酸达到理想平衡（AABI=0.972）时乳腺对MCP的摄取效果最佳。

Английский. Objective An experiment was conducted to study the effects of different balance models of amino acids in the artery blood flow by infusing amino acids into the external pudendal artery on nutrient uptake in the mammary gland of dairy goats. Method Three dairy goats at 2-3-year old of age with similar body weight and milk yield were intubated in the external pudendal artery and the abdominal subcutaneous vein, in this study. Different balance models of amino acids in the blood flow were made by infusing amino acids into the external pudendal artery. Arterio-venous plasma, at the start and the end of infusion, were collected to measure the changes of milk protein precursors (MPP), milk fat precursors (MFP) and milk lactose precursors (MLP) concentrations as well as nutrients uptake in the mammary gland. Result The uptake of MPP and MFP in the mammary gland was step up after infusing amino acids into the external pudendal artery (P＜0.05). Compared with the control group, the uptake of MLP by the mammary gland was increased after infusing, but there was no significant difference in the ideal amino acids model group (P＞0.05), meanwhile the difference was significant in the balance model group (P＜0.05). The milk production and milk content of the dairy goats were significantly different in the two groups (P＜0.05) compared with the control group. Conclusion Under the conditions of the experiment, the amino acids balance could change the uptake of milk components precursors in the mammary gland and in favor of the synthesis of milk. The uptake of milk components precursors in the mammary gland was optimum when the amino acid model was arrived at the ideal balance level (AABI=0.972).