ARS/SCA: Improving dietary protein quality in forage fed horses

This research will determine whether LYS and/or THR are limiting in predominantly forage diets for both growing and mature horses and will also increase our knowledge of total tract amino acid digestibility and the contribution of microbial populations to fecal amino acid losses. Future research can then focus on determining how the dietary requirements for the limiting amino acids change with diet composition and how differences in diet digestibility contribute to these differences in amino acid requirements. Ultimately, we would like to optimize the amino acid composition of ration balancer concentrates specific for grass and legume forages and promote the use high forage diets in growing and mature horses, without compromising dietary protein quality.