Department of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, 736 Wilson Rd., East Lansing 48824.
J Dairy Sci. 2020 Apr;103(4):3882-3893. doi: 10.3168/jds.2019-17278. Epub 2020 Feb 7.
Efficient production of heifers is fundamental to the productivity and sustainability of dairy farms. However, high preweaning morbidity and mortality rates are frequently reported worldwide, imposing substantial welfare and economic implications. A major contributing factor to disease susceptibility in the neonatal stage is the inability of calves to mount an effective immune response. Appreciation is now greater that exposure in utero to several stresses (nutritional, social, metabolic, and so on) during the last stages of pregnancy have downstream carryover effects in calves' health, growth, and development. Suboptimal intrauterine conditions during critical periods of development lead to changes in tissue structure and function that may have long-term consequences on the offspring's physiology and disease susceptibility. Indeed, preweaning metabolic function and growth are associated with future milk production. Thus, late-gestation carryover effects span into the lactating stage of the heifers. Nevertheless, researchers have been studying how to minimize these effects. This review will discuss the effects of maternal stress during late gestation on the offspring's growth, productivity, metabolism, and health. In addition, strategies focusing on maternal interventions that improve neonatal health will be discussed. A better understanding of the intrauterine conditions affecting calf health and growth may facilitate the design of management practices that could improve neonatal development and future cow productivity.
高效生产后备牛对于奶牛场的生产力和可持续性至关重要。然而，全世界经常报告高的新生牛发病率和死亡率，这对福利和经济造成了重大影响。导致犊牛在新生儿阶段易患疾病的一个主要因素是其无法产生有效的免疫反应。现在人们越来越认识到，在妊娠后期，犊牛在子宫内暴露于多种应激（营养、社会、代谢等）会对其健康、生长和发育产生后续的影响。在发育的关键时期，宫内条件不理想会导致组织结构和功能发生变化，这可能对后代的生理和疾病易感性产生长期影响。事实上，新生牛代谢功能和生长与未来的产奶量有关。因此，妊娠后期的代际影响会持续到后备牛的泌乳期。然而，研究人员一直在研究如何将这些影响降到最低。本综述将讨论母体在妊娠后期的应激对后代生长、生产力、代谢和健康的影响。此外，还将讨论关注改善新生牛健康的母体干预策略。更好地了解影响犊牛健康和生长的宫内条件，可能有助于设计管理措施，从而改善新生牛的发育和未来奶牛的生产力。
