Microbial protein

Microorganisms such as bacteria, micro-algae, fungi and protozoa are referred to as microbes and consist of high-quality protein. When they die, ruminants such as cows and sheep can digest this so-called microbial protein, whereas horses excrete it unused. Horses must therefore obtain protein and amino acids through their feed and can only utilise the proportion that can be digested in the small intestine.