Are you referring to BST? It’s not fed. Most milk processors won’t process milk treated with BST-although there is no difference in milk hormone levels (%) between BST cows and non BST cows. One thing we know is that if you supply hormones in the feed (blood levels) the body produces less. What feeders do are add feed additives that animals like so they eat more and produce more. Feed quality is #1 job for feeders.
Another problem with this theory, is that cattle hormones are of no problem to humans since our bodies do not process this hormone. Kids are expressing their hormones (growth, sexual, etc) due to an improved (?) diet (calories, proteins, etc). Each generation is larger because of our diet.