Identifying the systemic mode of action of microbial solutions controlling foodborne pathogen E. coli O157 shedding

食品安全和同一健康是加拿大牛肉行业面临的关键挑战，特别是在人畜共患传染病从农场动物、农场环境或食品向人类传播方面。在过去的二十年里，大量产生志贺毒素的大肠杆菌O157：H7(STEC O157)的大规模爆发给养牛业造成了数千万美元的损失。虽然XL食品暴发已经过去了几年，但另一起事件不可避免，加拿大牛肉行业有必要继续寻求新的方法，以减少这种细菌在食品生产链中的发病率。牛是STEC O157的主要宿主，这种病原体的传播是通过粪便排放到环境中，然后在加工过程中污染蔬菜作物、兽皮和肉类。已经测试了几种收获前的干预措施，包括疫苗和饲料添加剂，但没有一种方法能够有效地控制O157：H7大肠杆菌在牛体内的粪便脱落。与以前的方法不同，目前提出的NSERC联盟项目旨在开发一种新的基于直接饲喂微生物的方法来调节宿主-微生物的相互作用，以更好地促进肠道健康，并消除或降低STEC在牛肠道中的定植。该项目获得的信息和开发的技术将提供工业上适用的解决方案，以加强牛的健康并减少这种病原体在食物链中的流行。该项目产生的总体知识将帮助工业开发和实施具有成本效益的技术，以改善牛肉供应链上的食品安全，这将使农业利益攸关方和加拿大其他利益攸关方受益。

Food safety and one health are the key challenges faced by the Canadian beef industry, especially in the transmission of zoonotic infectious diseases from farm animals, the farm environment or food to humans. In the last two decades numerous large outbreaks of Shiga toxin-producing Escherichia coli O157:H7 (STEC O157) have led to tens of millions of dollars in losses to the beef industry. Although it has been a few years since the XL foods outbreak, another incident is inevitable and there is a need for the Canadian beef industry to continue to pursue new methods to reduce the incidence of this bacterium in the food production chain. Cattle are the main reservoir for STEC O157, and the transmission of this pathogen occurs through fecal shedding into the environment which then contaminates vegetable crops, hides and meat during processing. Several preharvest interventions had been tested, including vaccines, and feed additives, but none of the methods can effectively control fecal shedding of E. coli O157:H7 in cattle. Different from previous approaches, current proposed NSERC Alliance project aims to develop a novel direct fed microbe-based approach to regulate host-microbial interactions for better gut health and eliminate or lower STEC colonization in the gut of cattle. The information obtained and technologies developed by the project will provide industrial applicable solutions to enhance cattle health and reduce the prevalence of this pathogen in the food chain. The overall knowledge generated from this project will help industry to develop and implement cost-effective technologies to improve food safety along the beef supply chain that will benefit agricultural stakeholders and other Canadian stakeholders.