I know this has been asked a lot, i did a search on it an there were too many to list, But how much hay do i need to buy for (2) -18 mth old heifers and (2) -10 month old heifers.? Or how many round bales per ? i'm in South LA. so our winters or for the most part mild. usually cold from mi to late Dec. to March. Thanks and sorry for asking AGAIN!!!!!