Finding innovations to improve calf gastrointestinal health

加拿大乳制品业是该国最大的农业部门之一，贡献了近20%的人口

The Canadian dairy industry is one of the largest agricultural sectors in the country, contributing almost 20 billion dollars to the GDP every year. Despite this rapid growth, dairy calves continue to suffer from high rates of morbidity and mortality, with digestive disorders accounting for over half of reported illnesses and one-third of deaths. Several factors embedded within current management practices pose challenges to animal gut health, compromising their tract barrier function, normally referred to as "leaky gut". Studying the contributing factors of leaky gut is difficult because the conditions responsible for reducing intestinal barrier integrity can also affect the metabolism of other tissues. Probiotics promote gut mucosal health by limiting pathogen invasion and providing a stable, nutrient-rich environment for gut microbiota, thereby enhancing host digestive efficiency and immune function. Lactobacillus helveticus (LH) supplementation has been shown to improve gut barrier function through modulation of gut immune function. However, no studies have evaluated the effects of LH on barrier function, inflammation, and gut health in ruminants during preweaning and postweaning. Furthermore, there is currently limited information regarding models to study leaky gut in isolation. Previous research has unsuccessfully attempted to create models to induce leaky gut and has focused solely on the systemic inflammatory response without directly assessing gut permeability. Therefore, this proposal aims to improve our understanding of how this digestive disorder impacts host physiology and animal performance. This research encompasses the development of a model to better understand the aetiology of leaky gut and the models generated will serve to evaluate the impact of LH supplementation on barrier function, inflammatory response and energy metabolism.