Towards antibiotic-free feeding programs for piglets: The role of dietary nucleotides

仔猪断奶后腹泻是造成养猪业生产和经济损失的主要原因。传统上，养猪业通过使用含有高度消化和特殊成分（如喷雾干燥猪血浆和亚治疗水平的抗生素作为生长促进剂）的起始饲料来控制这种疾病。然而，由于担心这些产品对人类健康构成风险，公众对停止在猪饲料中使用动物产品和抗生素施加了巨大的压力。许多已被测试为替代抗菌生长促进剂的产品尚未被养猪业完全接受。这可能是由于许多这些产品，如高水平的氧化锌和有机酸，都有自己的问题。因此，有必要确定既有效又安全、成本效益高、环境风险最小的天然替代品。研究将探索新开发的富含核苷酸的酵母提取物（NRYE）调节断奶仔猪肠道发育、微生物群落和免疫反应的潜力。将研究使用酶补充剂来释放酵母培养产品中的碳水化合物成分，这可能对仔猪有保护作用。将研究NRYE和补充酶之间的潜在协同相互作用，以确定预防仔猪腹泻的有效治疗组合。疾病挑战模型将用于有效测试这些产品的潜在抗菌能力。该项目的结果将有助于制定断奶仔猪可持续营养管理方案的战略。

Post-weaning diarrhea in piglets is a major cause of productive and economic losses to the swine industry. Traditionally, the swine industry has managed this disease by utilizing starter diets containing highly digestible and specialized ingredients such as spray dried porcine plasma and sub-therapeutic levels of antibiotics as growth promoters. However, there is intense public pressure to discontinue the use of animal products and antibiotics in pig diets for fear that these products represents a risk to human health. Many of the products that have been tested as alternative antimicrobial growth promoters have not been fully accepted by the swine industry. This may be due to the fact that many of these products such as high levels of zinc oxide and organic acids have problems of their own. Consequently, there is a need for identifying natural alternatives that are not only effective but that are also safe, cost effective, and pose minimal environmental risks. Research will be conducted to explore the potential of a newly developed nucleotide-rich yeast extracts (NRYE) to modulate intestinal development, microbial communities, and immune response in weaned piglets. The use of enzyme supplementation to release carbohydrate components from the yeast culture product which may confer protective benefits to the piglet will be examined. The potential for synergistic interactions between NRYE and supplemental enzymes will be studied with a view of identifying a combination of effective therapies for prevention of piglet diarrhea. A disease challenge model will be used to effectively test the potential antimicrobial capabilities of these products. Results of the project will be useful in developing strategies for sustainable nutritional management options for weaned pigs.