Why is BGH/BST used to treat dairy cows?
BGH/BST is given to dairy cows to increase their milk production. BGH/BST is administered beginning after the ninth week of lactation Researchers showed in the 1930’s that cows injected with BGH/BST produce more milk on average than untreated cows. BGH/BST can be purified from pituitary glands of slaughtered cattle. Because the amount of BGH/BST that can be purified from the pituitary gland is so small, this has never been a practical source.