Welcome! I am Dr. Altman, a licensed veterinarian and happy to answer your questions today.
I am so sorry to hear that Carl is having this issue!
First, it sounds like he has colitis
which is inflammation of the colon and increases his urgency to defecate therefore ending in him having to go right at that moment and not make it outside.
The jelly you are noting is also an indication of colitis and would strongly urge you bringing a stool sample to your vet to evaluate to ensure that there is nothing medical that requires treatment. The great news is he is totally unaffected by the inflammatory response at this point and hopefully if you are able to get that sample evaluated (fresh or refrigerated) within the next 24 hours you will minimize any lethargy, vomiting, reduced appetite that potentially could be following...
In the meanwhile, reduce his food by 25% and supplement with white rice and boiled chicken
which is bland yet bulking to the gi tract +/- 1 tbsp canned pumpkin with each meal as well.
But the bloody stools should be addressed sooner rather than later to minimize any illness he might have in the next few days. Please let me know if I can be of any further assistance to you both!
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