The ration I use for my older bred cows is #14 silage, #10hay, and #8 corn stover. You may also be able to use straw instead of the stover. (I also have protein tubs out, or if the price is right I give 'em #2 of distillers, especially if it gets below 30* or so.)
My silage tested out at 2.4 as recieved for protein (7.8 dry matter) it was at 69% moisture, and my hay was 10 as recieved for protein (10.5 dry matter basis. So if you have hay that tests out okay for protein you should be okay with out the tubs. Never heard anyone say not to feed it to bulls? Just don't feed any moldy silage to bulls or breds.