Thanks for the additional information. It is good that she is feeling well, playful, and has not had any weight loss. It sounds like she has found a really great new home! It is also good that you have had a stool sample checked for parasites. If that test was done right after you got her from the shelter, it may be worthwhile to have this rechecked, because of the timing of the life cycles of different parasites so if she had gotten something at the shelter, it may not have shown up immediately. Be sure your vet knows about this problem with her stool, so they can do a direct smear of the stool as well to check for things like Giardia (protozoal parasite) and different types of abnormal bacteria as well as the common intestinal parasites that we normally look for.
The green color in stool generally comes from an increase in bile secretion from the liver. It does not mean something specific or worrisome, but that is just the source of the color.
If you are seeing normal formed stool initially and a little bit of loose stool at the end of a bowel movement, we would consider that normal and nothing to worry about. If you are seeing more pudding consistency stool, then we need to be doing something different.
The first thing I would try would be put her on a bland diet consisting of boiled chicken and rice and make that the absolutely only thing she eats (no yogurt and no bully stick) for about 72 hours and see what that does to her stool. If her stool normalizes on this, then gradually start mixing in her regular food over the next 3 to 5 days to see if that has any effect on her stool. The idea here is to reintroduce things one at a time and slowly so we can try to pinpoint which of these things may be contributing to the problem. If the stools are normal when she is completely back on her normal diet, then start again with the yogurt and watch for a few days. If still okay, then add back the bully stick to see what happens.
If you cannot get her stools normal when she is on the chicken and rice only, then there is something going on inside her gastrointestinal tract, and I would have her checked out by your vet. It could be that she just has an over growth of certain types of intestinal bacteria and may need some simple medications to get this problem resolved, or it is possible (although less likely) that there is something more serious going on.
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