Protein can be sourced either from vegetable sources such as soya beans, or more commonly we use meat from animal and fish sources in dog foods.
Simply put, Protein is made up from a range of muscle building blocks called Amino Acids.
When an animal consumes Protein, it will, during the digestive process, split the meat into its building blocks. It will then take from them what it needs to replace and rebuild its own muscle tissue, damaged or destroyed during previous physical activity. Other things within the dogs metabolism are also potentiated.