The "Meat Content" label is not protected by any law, as well as the "light" label that you can see on yogurts. So every manufacturer can interpret these labels in the way they want. High-end food manufacturers do not use any protein extracts to replace high-quality animal protein. So the amount of protein content specified on their packages (~23%) is almost perfect for a healthy pet.
High-quality products are a basis of perfect digestion (less food – fewer feces). Animal by-products (low-quality raw products with a high content of hooves, feathers, and claws) are poorly digested, so they are not used by high-quality food manufacturers. The ratio of meat – cereals in the food depends on the purpose of its usage: Puppy-food has 28-30% of proteins. The food for working and service contains a significantly higher amount of protein. The food for senior dogs contains decreased amount of proteins. The "Meat Content" can't be considered an index of food quality.
The amount of proteins can be evaluated from "Meat Meal" (dried and milled meat) Declaration. This kind of meat is one of the most qualitative products on the market because it does not contain any cartilages, bones, and connective tissues.
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