Functional roles of amino acids in regulation of milk fat and protein synthesis

由于计算机模型的改进，根据对奶牛饮食的描述来预测奶牛对氨基酸的吸收率，因此有新的机会来利用氨基酸营养的功能方面，而不是满足蛋白质构建块的要求。对其他动物的研究表明，氨基酸对生理和代谢产生一系列不同的影响，预期氨基酸可以类似地影响奶牛乳腺中的信号传导和基因表达也是合理的。我们的目标是在培养的乳腺细胞中，从蛋白质和脂肪合成的角度来表征对特定氨基酸的功能和分子反应（目的1），在哺乳期大鼠乳腺组织中（目标2）和奶牛（目标3），然后将描述牛奶成分对氨基酸反应的方程纳入工业合作伙伴的定量评估模型，该模型将用于制定膳食氨基酸酸谱以实现期望的乳成分响应（目标4）。Nutreco Canada Inc.将使用修订后的模型和从项目中获得的知识。优化客户牛群中奶牛的泌乳性能，提高加拿大牛奶生产的可持续性和安全性。该项目将雇用半名博士后研究员，一名研究生和两名本科生。

Due to improvements in computer models that predict rates of absorption of amino acids by dairy cows based on a description of their diet, there are new opportunities to exploit the functional aspects of amino acid nutrition, outside the scope of meeting requirements as building blocks of proteins. Studies in other animals have shown that amino acids exert a range of diverse influences on physiology and metabolism and it is not unreasonable to expect that amino acids can similarly affect signalling and gene expression in the mammary glands of dairy cows. Our objectives are to characterize the functional and molecular responses to specific amino acids in terms of protein and fat synthesis in mammary cells in culture (objective 1), in mammary tissue of lactating rats (objective 2) and cows (objective 3), and then to incorporate equations describing milk composition responses to amino acids into the industrial partner's ration evaluation model that will be used to formulate dietary amino acid profiles to achieve a desired milk component response (objective 4). The revised model and knowledge gained from the project will be used by Nutreco Canada Inc. to optimize lactational performance of cows in client herds and improve the sustainability and security of milk production in Canada. The project will employ ½ postdoctoral fellow, a graduate student, and 2 undergraduate students.