Abstract：
Ketosis is currently regarded as a major metabolic disorder of dairy cows, reflective of the animal\'s efforts to adapt to energy deficit while transitioning into lactation. Currently viewed as a pathology by some, ketosis is associatively implicated in milk production losses and peripartal health complications that increase the risk of early removal of cows from the herd, thus carrying economic losses for dairy farmers and jeopardizing the sustainability of the dairy industry. Despite decades of intense research in the mitigation of ketosis and its sequelae, our ability to lessen its purported effects remains limited. Moreover, the association of ketosis to reduced milk production and peripartal disease is often erratic and likely mired by concurrent potential confounders. In this review, we discuss the potential reasons for these apparent paradoxes in the light of currently available evidence, with a focus on the limitations of observational research and the necessary steps to unambiguously identify the effects of ketosis on cow health and performance via controlled randomized experimentation. A nuanced perspective is proposed that considers the dissociation of ketosis-as a disease-from healthy hyperketonemia. Furthermore, in consideration of a growing body of evidence that highlights positive roles of ketones in the mitigation of metabolic dysfunction and chronic diseases, we consider the hypothetical functions of ketones as health-promoting metabolites and ponder on their potential usefulness to enhance dairy cow health and productivity.
摘要：
酮病目前被认为是奶牛的主要代谢紊乱,反映了动物在过渡到哺乳期时适应能量不足的努力。目前被一些人视为病理学，酮症与产奶量损失和产周健康并发症有关，这些并发症增加了早期从牛群中去除奶牛的风险。从而给奶农带来经济损失，并危及乳制品行业的可持续性。尽管在缓解酮症及其后遗症方面进行了数十年的深入研究，我们减轻其所谓影响的能力仍然有限。此外，酮症与产奶量减少和房周性疾病之间的联系通常是不稳定的,并且可能被并发的潜在混杂因素所困扰.在这篇综述中，我们根据目前可用的证据讨论了这些明显悖论的潜在原因，关注观察研究的局限性，以及通过对照随机对照实验明确确定酮症对奶牛健康和性能的影响的必要步骤。提出了一个细微差别的观点，认为酮症-作为一种疾病-与健康的高酮血症分离。此外，考虑到越来越多的证据强调酮在缓解代谢功能障碍和慢性疾病中的积极作用，我们认为酮作为促进健康的代谢产物的假设功能，并思考它们对提高奶牛健康和生产力的潜在作用。
