Science. 1977 Dec 9;198(4321):1009-15. doi: 10.1126/science.198.4321.1009.
In the production of high quality protein, feed grains will continue to be used to finish cattle for market as long as economics dictates. Production systems could be developed that would make ruminant animals less competitive with humans for feed grains, but the costs of instituting such programs would be prohibitive. Sufficient genetic variation exists either between or within breeds for the cattle population to be adapted to new management programs and for current methods of beef production to be significantly improved.
在生产高质量蛋白质方面,只要经济条件允许,饲料谷物将继续用于育肥牛上市。可以开发生产系统,使反刍动物在饲料谷物方面与人类的竞争不那么激烈,但实施此类计划的成本将是巨大的。牛群之间或品种内部存在足够的遗传变异,可以使牛群适应新的管理计划,并显著改进当前的牛肉生产方法。