One of my bunnies keeps getting a messy bum most days at the moment. He is fed 35g of Science Selective a day, a spring greens leaf, half inch chunk of carrot, lots of good quality timothy hay and excel forage dried grass daily. Could any of this not be helping his delicate stomach? Also what other high fibre pellets could I give that bunnies like - I used to feed half and half of science selective and PF4P pellets from Bunnybasics site, but the rabbits preferred the SS and PF4P was really dusty and annoying so I stopped using it and I'm sure the bum problem has got worse since. The other bunny who lives with him is fed the same and never has any problems. Any advice would be appreciated, thanks.