Hello, my name is***** and I have over 20 years of experience as a veterinarian. I am sorry to hear that Captain has a yellowish, mucous coating on his stools.Does his stool look like the one in this link?: http://i804.photobucket.com/albums/yy322/schmep/GetAttachment.jpgIf so what you are seeing is mucous, and that is secreted by the colon in response to irritation/inflammation. The most common causes for this in dogs include eating something new, eating foreign material or particular types of gastrointestinal parasites (for example whipworms).Since you talk about treats
, is he being fed new treats? If so I suspect that may be the trouble for your fellow. Not that there is anything wrong with the treats, but they just may not agree with him.At this point if he feels well otherwise and his stools aren't loose I would stop the treats entirely and see if he responds to that alone.If his stools are at all loose too then you might try feeding
a bland diet with added fiber to soothe his colon for a few days. A homemade diet for this is 1/3 boiled, lean hamburger or boiled, white, skinless chicken
, all fats and juices drained off the meat after cooking, and 2/3 boiled, white rice or pasta. Add 1-2 tablespoons of canned pumpkin, not pie filling just pumpkin, to each meal for fiber.I also recommend submitting a fresh stool sample to his veterinarian just to make sure that he hasn't picked up a parasite. Sometimes we will worm with a broad spectrum wormer like Panacur (fenbendazole) just in case, as it is easy to do and won't hurt him and may help.Please let me know if you have any further questions.