I agree with Wayne. My cats don't like changes in diet. I would definitely stick to the same food and mix a bit of wet in with dry. Do this over the course of about a week, then gradually keep increasing the ratio of dry to wet until they are eating all dry. Then you can give a bit of wet food every now and again as a treat. Is there a reason you keep switching foods??

I'm wondering though, is the blood bright red or dark? I know that in humans if the blood is really dark (almost black) then it's a possible sign of internal problems. If it's bright red then it could just be a problem with maybe a tear in the anus??? It heals over then with a big BM, it tears again?? I do think a good diet with a substantial % of fibre might improve the situation. But I'm not saying you don't need to take her to a vet. I would watch carefully and if there is any change at all, rush Sabrina in, and in the meantime, I would still take in a stool sample for testing. Hope that helps.

slick
max & speckles