Studies on the relationship between lower-cost low protein complexity feed and genetics with health and growth performance in pigs

通过交替饲养策略降低生产成本是养猪业的研究重点。我们最近的研究表明，只要猪不生病，就可以用低成本、低动物蛋白(低蛋白质复杂性)的日粮喂给育苗猪，而不会对生产性能产生负面影响，直到市场体重。我们还确定了与提高生长速度和抗传染病能力相关的猪的基因类型，但在商业养殖条件下，饲料质量、基因和健康对猪生长性能的累积影响尚不清楚。这项研究将考察低成本日粮的应用，并调查对传染病遗传抵抗力提高的猪在这些日粮/条件下是否表现更好。商业农场的猪将在两个不同的季节饲喂低成本、低动物、低复杂性蛋白质日粮或常规日粮。猪将被称重多次并监测疾病；患病的猪将被尸检以诊断疾病病因。将对血液、粪便和鼻拭子进行猪病原体检测，分析血清免疫/生长生物标记物，并对猪进行先天抗病基因缺陷的基因鉴定。屠宰时，将评估一部分猪的屠宰率和瘦肉率，以确定日粮对屠体质量的影响。我们将确定在商业环境中使用替代的低成本、低动物蛋白饮食的可行性。我们还将确定在商业条件下影响生长性能的参数，以及在生长的不同阶段对感染剂的抵抗力，并将这些参数与生产率、市场重量和屠体质量联系起来，以帮助最大限度地提高这种替代价格较低的苗圃饲料的经济效益。这项研究将为生产者、饲料和遗传公司使用更便宜的饲料以及选择更健壮的猪基因型和/或具有更好生长性能的猪提供宝贵的知识。对加拿大人来说，结果将是一个更强大的养猪业，动物福利得到改善，消费的猪肉更安全，抗菌剂的使用减少，从而有助于对抗抗菌素耐药性的战争。

Reduction of production cost via alternate feeding strategies is a research priority of the swine industry. Our recent study showed lower cost reduced animal-protein (low protein complexity) diets can be fed to nursery pigs without negative impacts on performance up to market weight as long as pigs do not become diseased. We have also identified pig genotypes associated with improved growth rate and infectious disease resistance, but the cumulative impact of feed quality, genotype, and health on pig growth performance under commercial farming conditions is unclear. This study will examine the application of lower-cost diets, and investigate whether pigs with improved genetic resistance to infectious diseases perform better under these diets/conditions. Pigs on commercial farms will be fed either a lower cost reduced animal low complexity protein diet or conventional diet during 2 different seasons. Pigs will be weighed multiple times and monitored for disease; sick pigs will be necropsied to diagnose disease etiologies. Blood, feces and nasal swabs will be tested for the presence of swine pathogens, and serum immune/growth biomarkers will be analyzed, and pigs genotyped for defects in innate disease resistance genes. At slaughter a subset of pigs will be evaluated for carcass dressing percentage and lean yield to determine the impact of the diets on carcass quality. We will determine the feasibility of using alternative lower cost reduced animal protein diets in a commercial setting. We will also identify parameters that impact growth performance under commercial conditions and resistance to infectious agents during the various stages of growth and relate these to productivity up to market weight and carcass quality, to help maximize the economic benefits of this alternative less expensive nursery diet. This study will provide valuable knowledge usable by producers and feed and genetics companies towards the use of less expensive feeds as well as selection of more robust pig genotypes and/or pigs with superior growth performance. The result for Canadians will be a stronger swine industry with improved animal welfare, safer pork for consumption, and reduced use of antimicrobials thus helping in the war on antimicrobial resistance.**************