Enhancing functional intestinal development for improved growth and efficiency in poultry

营养学家认为胃肠道功能障碍是家禽生存和生产力的潜在限速因素。这种认识是由于在遗传改良和限制使用促生长抗菌药物（AGP）和抗球虫药物方面取得的进展，出现了关于消化道发育和功能的想法。功能性肠道是许多生理学和微生物学参数在复杂的相互作用中的状态的结果，导致严格控制的粘膜免疫平衡。在孵化后的即刻期间，肠道组织的高代谢率和细胞周转导致膳食营养素（尤其是氨基酸）的大量首过利用，以维持肠道功能。谨慎的预期是，用不含AGP的饲料饲养的家禽将经历更高的肠道健康问题发生率和更长时间的免疫挑战。炎症和免疫反应对营养代谢的影响可能会损害身体蛋白质积累，生长和所有其他代谢过程的营养物质的可用性。我的研究计划的长期目标是通过整合母体，卵内和早期孵化后营养策略来揭示调节家禽肠道功能和健康的因素和过程，以支持胚胎持续肠道发育到早期孵化后时期，以优化营养素利用，提高家禽生产力并减少抗生素的使用。本提案的具体目的是研究调节适应性消化和吸收反应的机制，以及它们与生长和发育的关系，以促进设计有效的无抗生素起始饲料，特别是在肠道病原体可能影响有效生产的条件下。该提案将利用我在肠道病原体挑战模型方面的经验，研究营养与肠道健康之间的相互作用。通过表征肠道营养素的使用，将以水平和与其他营养素的相互作用以及给药时间的形式发现影响稳态平衡的营养素的量。这方面的知识将是至关重要的，在开发启动饮食，以“条件”的肠道更好的营养利用和程序的代谢，最终影响生产效率，胴体组成和肉质。该研究将涉及使用动物营养和尖端研究技术和仪器的先进技术，如基因组测序仪，先进的显微镜，同位素示踪剂）。理解熟练使用这些技术来提高饲料效率在学术和工业环境中都具有很高的兴趣，并且在研究计划中培训的HQP的科学事业中将非常有用。

Nutritionists perceive dysfunctional gastrointestinal tract as a potential rate-limiting factor in the survival and productivity of poultry. This perception has been fostered by the emergence of ideas concerning the development and function of the digestive tract in the light of advances in genetic improvement and restriction on the use of growth promoting antimicrobials (AGP) and anticoccidial drugs. A functional gut is the result of the status of many physiological and microbiological parameters in a complex interplay leading to a tightly controlled mucosal immune balance. The high metabolic rate and cellular turnover of gut tissues in the immediate period post-hatch result in substantial first-pass utilization of dietary nutrients, especially amino acids, to maintain gut function. It is prudent to expect that poultry raised on feeds without AGP will experience higher incidences of intestinal health problems and prolonged period of immunological challenges. The consequences of the inflammatory and immune responses on nutrients metabolism could impair the availability of nutrients for body protein accretion, growth and all other metabolic processes. The long-term goal of my research program is to unravel factors and processes that regulate intestinal function and health in poultry by integrating maternal, in-ovo and early post-hatch nutrition strategies to support continuous gut development at embryonic through to early post-hatch period to optimize nutrients utilization for enhanced poultry productivity and reduced antibiotic use. The specific aim of the this proposal is to study mechanisms mediating adaptive digestive and absorptive responses and how they relate to growth and development to facilitate design of effective antibiotic free starter diets, particularly in conditions where enteric pathogens may otherwise compromise efficient production. The proposal will capitalize on my experiences with enteric pathogen challenge models to study the interactions between nutrition and gut health. By characterizing intestinal nutrient usage, amounts of nutrients that affect homeostatic balance will be discovered in the form of levels and interactions with other nutrients, and the timing of administration. This knowledge will be pivotal in developing starter diets to “condition” the gut for better nutrient utilization and program metabolism that ultimately affects production efficiency, carcass composition, and meat quality. The research will involve the use of advanced techniques in animal nutrition and cutting edge research techniques and instrumentation such as genomic sequencer, advanced microscopy, isopote tracers). Comprehending skillful use of these techniques to enhance feed efficiency is of high interest in both academic and industrial settings and will be very useful in furthering scientific careers of the HQP trained in the research program.