Development of new tools for genetic selection for a sustainable poultry industry (CHIPSUS)

英国的公共政策要求减少温室气体排放和氨，以达到国际目标。在家禽养殖方面，有必要保持竞争力，并减少因浪费饲料和非生产性禽类而产生的成本。实现这些育种目标涉及饲料转化率、生育力、商业性状表现以及与抗病性和动物福利相关的宜居性等性状。正是这些相同的性状影响肉鸡或蛋鸡每公斤产品的温室气体和氨排放。肉鸡生产对环境影响的生命周期评估（LCA）表明，饲料占供应链能源消耗的80%，温室气体排放的82%，臭氧消耗排放的98%，以及酸化和富营养化气体的96%。相比之下，农业投入和排放，主要来自供暖和通风，对这些影响的贡献很小。事实证明，通过标准性状记录难以改善这种性状组合的育种目标;性别和年龄限制、遗传力低和测量成本都是进展的障碍。DNA技术的最新发展有望克服这些障碍，特别是在高通量处理密集的单核苷酸多态性（SNP）。与此同时，出现了基因组选择的思想，其中密集标记信息主要用作整个育种价值的预测。在家禽中开发基因组选择的进展受到需要开发和实施基于SNP变体的广泛目录的密集和相关的鸡基因分型芯片测定的阻碍。为了发展这一点，需要一个新的研究倡议，如这里所建议的。该项目的总体目标是使用全基因组鸡SNP小组开发和实施可持续评估和选择工具，从而加速减少英国和全球的温室气体和氨排放，并提供路线图和关键工具整个行业都可以遵循。这将通过五项任务来实现：（i）通过DNA样品的高通量序列分析，建立家禽品种内和品种间基因组变异的数据库;（ii）设计和验证一种新的高通量基因分型方法;（iii）对具有良好表征的EBV相关性状的肉鸡进行基因分型;（iv）开发和验证基因组预测因子，以及（v）优化将这些工具应用于育种系统的方法。该项目的直接好处在于减少家禽单位产品的温室气体潜力和氨，保持英国产业的竞争力，并通过提高宜居性改善动物福利，而且还将通过提高FCR为释放谷物和相关土地用于其他目的创造机会。根据性状的不同，遗传增益的加速预计为20%至40%。遗传选择带来的好处将是永久性的，并随着时间的推移而积累，而且风险很低。

UK public policy is demanding reductions in greenhouse gas emissions and ammonia to meet international targets. In poultry breeding there is a need to maintain competitiveness, and to reduce costs arising from wastage of feed and non-productive birds. Addressing these breeding goals implicates traits such as feed conversion ratio, fertility, performance in commercial traits, and liveability associated with disease resistance and animal welfare. It is these same traits that affect greenhouse gas and ammonia emissions per kilogram of product in broilers or layers. Life Cycle Assessment (LCA) of the impact of broiler production on the environment suggests feed accounts for 80% of supply chain energy use, 82% of greenhouse gas emissions, 98% of ozone depleting emissions, and 96% of acidify and eutrophying gases. In contrast, farm inputs and emissions, mostly from heating and ventilation, only contribute towards these impacts to only a minor degree. Such a breeding goals with this combination of traits has proven difficult to improve through standard trait recording; with sex and age limitations, low heritability and costs of measurement all contributing barriers to progress. Recent developments in DNA technology promise to overcome these barriers, in particular in high throughput processing of dense single nucleotide polymorphisms (SNP). Concurrently, the idea of genomic selection has emerged, in which dense marker information is used primarily as a predictor of the whole breeding value. Progress in developing genomic selection in poultry is hampered by the need to develop and implement a dense and relevant chicken genotyping chip assay, based upon an extensive catalogue of SNP variants. To develop this requires a new research initiative, as proposed here. The overall aim of this project is to develop and implement sustainable evaluation and selection tools using a genome-wide chicken SNP panel and in so doing accelerate the reduction in greenhouse gas and ammonia emissions in the UK and worldwide, and provide the route map and key tools for the whole sector to follow. This will be achieved through five tasks: (i) create a database of genomic variation within and between poultry breeds by high throughput sequence analysis of DNA samples; (ii) design and validate a novel, high-throughput genotyping assay; (iii) genotype broilers with well characterised EBVs for relevant traits; (iv) develop and validate genomic predictors, and (v) optimise methods to implement these tools into the breeding system. The direct benefits of this project lie in the reduction of greenhouse gas potential and ammonia per unit product in poultry, maintaining the competitiveness of the UK industry, and in the improvement of animal welfare through increased liveability, but also opportunities will be created for releasing grain and associated land for other purposes through the improvement of FCR. The acceleration of genetic gain is anticipated to be of the order of 20 to 40% depending on the trait. Benefits accrued by genetic selection will be permanent and accumulate over time, and are achieved at low risk.