Not sure if this is helpful, but I had a dog who went blind about a year before she died. She did sometimes bite people when she was startled but never in an aggressive way, more of a protective thing. She didn't know they were there and they scared her and she reacted. But she went through that biting stage for maybe 3 months and then she became "used" to being blind, and my cat, my oldest one, took on being a seeing eye cat for her all on her own and would groom her and bop her on the head gently with her chin when she was finished and would lead her to the food and such, and they got on quite well like that for the last year of my dogs life. Kit