Thanks additional information. He certainly doesn't sound like he feels well, does he???
I understand about a thermometer but it's often good to double check the temperature in these cases. If you manage to get your hands on one, normal is between 100 and 102.5.
Gum color is good; dehydrated dogs often have a more reddish color to their gums.
They also often feel tacky rather than moist.
No abdominal pain is also a plus.
It's quite possible that he picked up a viral or bacterial infection while he stayed at the kennel, unfortunately; this is always a possibility regardless of how clean and reputable a facility may be.
Internal parasites could also cause his symptoms as could IBD issues or systemic disease, etc.
But, regardless, the following would be my suggestions:
1. Bismuth subsalicylate (brand name Pepto Bismol here in the States) can be given as long as Scooby isn’t vomiting and isn’t currently taking any anti-inflammatory drugs. Since liquid formulations are more effective than the pill forms, the dose would be 1 teaspoon per 5 -10 lbs of body weight 2-3 times a day.
, if he weighs 50 lbs, then you would give him5-10 mlsor one to two teaspoons at one time.
This drug can discolor the feces to a gray-black or greenish color though so this shouldn't concern you if it happens.
Pepto bismol should not be given to vomiting dogs since it contains salicylates (the active ingredient in Aspirin) which can irritate the stomach.
2. Get him to drink Pedialyte if you can since electrolytes can be replaced which have been lost in the looser stools. Many dogs feel lousy when electrolyte-depleted, just like we do.
3. I'd start him on a good quality, canine probiotic such as Forti Flora or Resources Protegrity GI. These products can be extremely useful issues (and to help strengthen the immune system as well). They may be available at local pet/grain stores or can be purchased online.
4. I know his appetite is off but offer a bland diet of 1 part boiled chicken (or hamburg) to 4 parts 20-minute white rice. Offer only a small amount of one time, 3-4 times through the day. I would not feed any regular dog food or treats.
Hopefully, the above will be sufficient to show improvement and thus avoid the stress of a vet visit. However, if he continues to behave as you're currently seeing, then he may need stronger anti-diarrheal drugs and/or fluids (if he's dehydrated).