Means to improve the robustness of newly weaned pigs exposed to mycotoxin-contaminated feeds **

真菌毒素，包括脱氧雪腐镰刀菌烯醇（DON），是真菌感染的次级代谢产物，经常发生在谷物和玉米中。猪是最易受DON影响的牲畜物种，暴露症状包括饲料摄入量和生长减少，这意味着加拿大猪肉行业仅受到适度DON污染就损失了6000万美元的利润。加拿大生物系统公司(CBS)正在开发一种新型饲料添加剂（NUTRA-MIX），可用于减轻DON对猪的负面影响。据推测，含有吸收剂、酵母多糖和维生素的饲料补充剂（即NUTRA-MIX）将通过刺激肠道发育和改善免疫系统稳健性来缓解暴露于DON的断奶仔猪生长性能的降低。目的是评估NUTRA-MIX对生长性能的影响，并通过仔猪在保育期暴露于受DON污染的玉米的肠道健康和发育以及免疫系统功能的指标来了解其作用模式。断奶后，将256头猪随机分配到32个围栏中，每个围栏8头猪，并以2X2析因安排分配到由霉菌毒素污染（3 mg DON/kg全价饲料）或未污染玉米制成的保育饲料中，并添加或不添加NUTRA-MIX。增长表现，对E.大肠杆菌感染，并评估肠道健康和发展将被确定。将测量对疫苗接种的体液和细胞介导的免疫应答。如果我们的假设得到支持，毫无疑问，CBS将立即将这些结果转化为有利于加拿大养猪业的改进产品，特别是在生产者寻找抗生素替代品以促进生长并改善猪的健康和福祉的情况下。从项目的结果扩大业务也将确保CBS的增长，增加公司的收入，并确保其员工的工作保障。

Mycotoxins, including deoxynivalenol (DON), are secondary metabolites of fungal infections that frequently occur in cereal grains and corn. Pigs are the most susceptible livestock species to DON and symptoms of exposure include reduced feed intake and growth, which represents a $60 million loss of profits for the Canadian pork industry with only modest DON contamination. Canadian Bio-Systems Inc. (CBS) is developing a novel feed additive (NUTRA-MIX) that can be used to mitigate negative impact of DON for swine. It is hypothesized that a feed supplement containing absorbents, yeast polysaccharides, and vitamins (i.e. NUTRA-MIX) will mitigate the reduction in growth performance for weanling pigs exposed to DON by stimulating gut development and improving immune system robustness. The objectives are to evaluate the effect of NUTRA-MIX on growth performance and understand its mode of action through indices of gut health and development and immune system function of weanling pigs exposed to DON-contaminated corn during the nursery period. After weaning, 256 pigs will be randomly allocated to 32 pens of 8 pigs and assigned to nursery diets made with mycotoxin-contaminated (3 mg DON/kg complete diet) or uncontaminated corn and with or without NUTRA-MIX supplementation in a 2X2 factorial arrangement. Growth performance, resilience to an E. coli infection, and evaluation of gut health and development will be determined. Humoral and cell-mediated immune responses will be measured in response to vaccination. If our hypothesis is supported, there is no doubt that CBS will immediately translate these results into improved products that will benefit the Canadian swine industry, particularly as producers look for alternatives to antibiotics for growth promoting benefits and to improve the health and wellbeing of their pigs. Expanded business from the results of the project will also ensure the growth of CBS, increase revenue for the company, and ensure job security for its employees.