Enzymes break down nutrient molecules into their building blocks. Carbohydrates are broken down into monosaccharides, fats into fatty acids and monoglycerides, nucleic acids into nucleotides, and proteins into amino acids. The horse has a small stomach. The horse's small intestine is the main organ of their digestive system. Pancreatic enzymes are found in their small intestine to aid digestion. There is also protease which helps emulsify proteins and amino acids; furthermore, the horse does not have a gallbladder, meaning bile constantly flows into its small intestine; It also helps break down fats. Foods that are digested are absorbed through the walls of the small intestine and transported through the bloodstream to cells that need nutrients. I think the cow has a more effective small intestine than the horse, while the cow has a gallbladder, so bile does not constantly flow through her body; it is also equipped with a valve that prevents the backflow of food, something that the horse does not have. The cow also has three sections of the small intestine, digestion can also take longer, this means that the absorption of nutrients and liquids does not happen all at once in one section, as the horse has a small stomach sac . For these reasons, I think the cow has the most efficient small intestine. The pH value of the fermenter stomach of both ruminants and the hindgut is