Baldwin R L, Smith N E, Taylor J, Sharp M
J Anim Sci. 1980 Dec;51(6):1416-28. doi: 10.2527/jas1981.5161416x.
Several opportunities for improving animal efficiency through manipulation of metabolism are discussed. The first opportunity is through identification and selection of animals achieving close to theoretical efficiencies. Based upon differences between highly efficient and average animals, the estimated opportunity for improvement is 20%. A second opportunity for improvement is through manipulation of apparent maintenance requirements. Several contributors to differences in efficiencies are considered. One is the contribution of differences in relative organ weights to differences in apparent maintenance requirements. A potential benefit in the order of 10 to 20% through selection or manipulation seems possible. Manipulations of ion transport and protein turnover could yield maximum benefits of 30 and 15%, respectively. However, complete elimination of these processes is not feasible. Without ion transport, membrane potentials would not be maintained and, without turnover, many important regulatory processes would be affected. the limit to manipulation of these characteristics is unknown. A third opportunity for improvement of animal efficiency is through improvement of apparent biosynthetic efficiency by manipulation of patterns of nutrient utilization. If we could produce, through hormonal or other types of manipulations, an optimum pattern of nutrient use, decreases in heat increments of production in growing animals in the order of 50% might be achieved.
讨论了通过调节新陈代谢来提高动物效率的几个机会。第一个机会是识别和选择接近理论效率的动物。根据高效动物和普通动物之间的差异，估计的改进机会为20%。第二个改进机会是通过调节表观维持需求。考虑了导致效率差异的几个因素。一个是相对器官重量的差异对表观维持需求差异的影响。通过选择或调节，可能会有10%到20%的潜在益处。离子转运和蛋白质周转的调节分别可产生30%和15%的最大益处。然而，完全消除这些过程是不可行的。没有离子转运，膜电位就无法维持，没有周转，许多重要的调节过程就会受到影响。这些特征调节的限度尚不清楚。提高动物效率的第三个机会是通过调节营养利用模式来提高表观生物合成效率。如果我们能够通过激素或其他类型的调节产生最佳的营养利用模式，那么生长动物生产热增量可能会降低50%左右。
