Well I never thought goats would eat my Christmas tree but he surely did...And my horse too....They know what to eat and if your cat litter smells line pine tree they will try that too....I know chickens do and Rabbits and guinea pigs smell the food first...I would put branches down for them so they can nibble at floor level...I will bet they will nibble then leave it alone...I know my goat will nibble paper even and he enjoys tortilla chips mor than I do. I suggest you vegetarian diet through this you get more results about what is a vegetarian diet .
I was also very confused about the feed of rabbits and tried different things but results were not awesome. I was reading some papers written by superiorpapers.com reliable source which guide me to try asking my problem here and thanks to the guys for best help.
Depends how hungry they are?