My dwarf lop, Brian has suddenly stopped cleaning himself and waste is collecting around his rear. I know this can be a sign of illness, but he seems otherwise fine! I've managed to get hold of him and cut a couple of lumps off, but I'm really scared off cutting him. He is becoming very angry with my unwanted attention, and is bounding away when he sees me coming! His partner, Ruby is also getting quite upset with me. It's very awkward as it's cold outside and they are garden bunnies, so I don't want to wash him for fear that he may catch a cold. Should I take him to the vet? They could possibly sedate him and shave his bottom to clear the problem. Any advice would be much appreciated.