Nutritional regulation of rumen epithelium

点击翻译按钮获取中文摘要

Commercial dairy production systems rely on energy dense diets with elevated levels of rapidly fermentable carbohydrates to improve production efficiency. However, consumption of high grain/low-fibre diets by ruminants commonly leads to an accumulation of volatile fatty acids (VFAs) and lactate within the rumen causing ruminal acidosis. The impacts of acidosis include reduced feed intake, rumen epithelium damage and, subsequently, can lead to liver damage, laminitis and death. This program of study will characterize an acidosis-induction model and the impacts of the disease on rumen epithelial cell turnover and expression of genes regulating protein turnover. This comprehensive biological model will allow subsequent development of nutritional strategies to enhance rumen epithelium adaptation and recovery to ruminal acidosis. The central hypothesis is; in lactating cows suffering from subacute ruminal acidosis the reduction of ruminal lactate along with therapeutic treatment with leucine will reduce protein degradation pathways and increase cell proliferation of the rumen epithelium. This program of study will lead to improvements in the digestive function, productivity and well-being of lactating dairy cows.