Why have cows been injected with proteins?

Cows have been injected with proteins for Bovine somatotropin or BST is a protein-based hormone that has no effect to a cow. Bovine somatotropin will only affect the growth of the cow. Cow's milk is also improved according to study because of the protein injected.

I’m not exactly sure what your trying to ask, but if it’s how an organelle is similar to a body system or a part a nucleus is like a in function. but i don’t fully understand what you’re trying to ask