Department of Animal and Poultry Sciences, Virginia Tech, Blacksburg, VA, 24060, USA.
Department of Animal and Poultry Sciences, Virginia Tech, Blacksburg, VA, 24060, USA.
Theriogenology. 2020 Jul 1;150:27-33. doi: 10.1016/j.theriogenology.2020.01.041. Epub 2020 Jan 20.
As the population grows and shifts demographically, the resulting increase in demand for beef and milk necessitates improvements in the sustainability of ruminant livestock production systems. Ruminant livestock contribute to ensuring global food security because they have the ability to up-cycle non-human-edible products into meat and milk products with notable nutritional value. However, ruminant livestock also pose a challenge to global food sustainability because they are resource-intensive to produce and contribute substantially to agricultural greenhouse gas emissions. As such, improving environmental impacts of ruminant livestock production globally is an essential goal. There are a number of strategies that can be employed to enhance sustainability of ruminant production systems; however, improving reproductive efficiency is among the more efficient, because an increase in reproductive success will reduce the number of cows needed to produce a target quantity of beef. This reduction in the cow herd size helps limit the number of unproductive animals retained in the herd, thereby reducing the environmental maintenance cost of livestock production. Additionally, proper application of reproductive technologies enables faster and more targeted advances in genetic gains, which can be leveraged to produce phenotypes that are resource-use-efficient and well-adapted to their production environment. Optimizing reproductive efficiency can be accomplished through improved genetic selection for fertility and fecundity; applying more effective use of assisted reproductive technologies; and coupling reproductive and nutritional management to optimize likelihood of reproductive success. Collectively, applying these approaches will be essential when working to ensure ruminant livestock's contribution to global food security.
随着人口的增长和人口结构的变化，对牛肉和牛奶的需求增加，这就需要提高反刍家畜生产系统的可持续性。反刍家畜有助于确保全球粮食安全，因为它们能够将非食用人类产品转化为具有显著营养价值的肉类和奶制品。然而，反刍家畜也对全球粮食可持续性构成挑战，因为它们的生产需要大量资源，并对农业温室气体排放做出重大贡献。因此，改善全球反刍家畜生产的环境影响是一个重要目标。有许多策略可以用来提高反刍动物生产系统的可持续性；然而，提高繁殖效率是更有效的策略之一，因为繁殖成功率的提高将减少生产目标数量牛肉所需的奶牛数量。牛群规模的这种减少有助于限制牛群中保留的非生产性动物的数量，从而降低畜牧业生产的环境维护成本。此外，适当应用繁殖技术可以更快、更有针对性地实现遗传增益，从而可以利用这些技术来生产资源利用效率高、适应其生产环境的表型。通过提高对生育力和繁殖力的遗传选择、更有效地应用辅助生殖技术以及将生殖和营养管理结合起来以优化生殖成功率的可能性，可以实现繁殖效率的优化。总的来说，在努力确保反刍家畜对全球粮食安全的贡献时，应用这些方法将是必不可少的。
