Maternal and Lactocrine Programming of the Neonatal Gut

加拿大有1500多万只反刍动物，生产牛奶和肉类，为加拿大经济贡献了400多亿美元。在加拿大大约50，000个农场饲养的反刍动物遵循动物福利的最高标准，但幼龄动物的胃肠道（GIT）疾病和代谢紊乱仍然严重威胁着动物福利和农业的盈利能力。我的DG的第一阶段的重点是表征GIT和代谢适应产粮反刍动物出生后，重点是初乳，牛奶喂养和断奶方案。虽然这项研究在行业中产生了影响，但它没有考虑母体信号如何在产前和通过初乳生物活性影响后代。目前缺乏研究特征的反刍动物的因素，包括反刍动物的饮食管理，影响colostrogenesis在反刍动物，因此，后代的发展。此外，有必要区分产前编程-妊娠动物中过量营养供应的影响及其对发育中胎儿的后续影响-和乳分泌编程-通过消耗初乳或牛奶将生物活性因子从母体传递给后代，这可能会因增加初乳营养摄入而改变。本研究的第一个假设是初乳生物活性物质可以调节幼龄反刍动物的GIT功能和代谢。将我的研究计划扩展到包括初乳编程，另一个假设是妊娠后期营养干预可以改变初乳生物活性，这反过来又改变了后代的GIT功能和代谢（目标2和3）。双胞胎轴承母羊是合适的实验模型，这两个研究目标，由于其减少管理强度和分配到不同的产后治疗遗传相似的双胞胎羔羊的能力。 这项研究将提供一个全面的理解的综合反应的信号，后代收到产前或通过哺乳期，可能印记代谢和GIT节俭。DG提案中的基础研究将是设计更多应用的基础，NSERC联盟驱动的牛研究。总的来说，这些研究重点将使我们能够实现我们的目标，即为反刍动物在反刍期间开发营养方案，以生产高质量的初乳，并利用初乳和牛奶来改善反刍动物的发育和预防疾病。这将通过改善生长和健康，使反刍动物生产者在经济上受益，并创造减少抗菌剂的替代品，有效解决当前许多社会经济和环境问题。

There are over 15 million ruminants in Canada producing milk and meat, which contributes over 40 billion dollars to Canada's economy. The ruminants raised on approximately 50,000 farms throughout Canada follow the highest standards of animal welfare, however gastrointestinal (GIT) diseases and metabolic disorders in young stock are still serious threats to animal welfare and the profitability of agriculture. The first phase of my DG focused on characterizing the GIT and metabolic adaptations in food-producing ruminants postnatally, with an emphasis on colostrum, milk feeding and weaning regimens. Although this research has generated impact in the industry, it did not consider how maternal signals could influence offspring prenatally and via colostrum bioactivity. There is currently a paucity of research characterizing prepartum factors, including prepartum dietary management, that impact colostrogenesis in ruminants and consequently, the development of the offspring. Further, it is necessary to distinguish between prenatal programming - the effects of excess nutrient provision in the gestating animal and their subsequent effects on the developing fetus - and lactocrine programming - the transmission of bioactive factors from the dam to offspring via consumption of colostrum or milk that may be altered as a consequence of increased prepartum nutrient intake. The first hypothesis of this research is that colostrum bioactives can regulate GIT function and metabolism of the young ruminant. Extending my research program to also include prepartum programming, an additional hypothesis is that late gestation nutritional interventions can alter colostral bioactivity, which in turn alter GIT function and metabolism of the offspring (Objectives 2&3). Twin-bearing ewes are the suitable experimental model for both research objectives due to their reduced-management intensity and the ability to allocate genetically similar twin lambs into different postnatal treatments. This research will provide a comprehensive understanding of the integrated responses to signals the offspring receive prenatally or through lactation that may imprint metabolic and GIT thriftiness. The basic research from the DG proposal will be fundamental to designing more applied, NSERC Alliance driven research with cattle. Collectively, these research foci will enable us to meet our goal of developing nutrition regimens for ruminants during the prepartum period to produce high-quality colostrum and utilize colostrum and milk to improve ruminant development and prevent disease. This will benefit ruminant producers economically through improved growth and health, as well as create alternatives that reduce antimicrobials, effectively addressing the many current socio-economic and environmental concerns.