Hello, my name is***** and I have over 20 years of experience as a veterinarian. I am sorry to hear that your little one CoCo is passing clear, jelly like (mucous) along with his stools, is passing stools all over the house, and scooting.
Mucous in the stool indicates colonic irritation, and scooting also points toward colitis (inflammation of the large intestine).
In most cases mucous in the stools and scooting are triggered by eating something they should not, too much table food, too many treats or something they find outdoors or gastrointestinal parasites.
More serious causes in puppies include viral or bacterial infections, a dietary allergy or sensitivity, congenital internal organ failure (kidney or liver disease), or a partial gastrointestinal obstruction.
In a young dog, especially one that hasn't finished his vaccine series, a viral infection such as Parvo virus, parasites or a foreign body leading to a partial gastrointestinal obstruction would be the most likely cause and these can be deadly. Worms can cause loose stools with mucous.
Because he is young, this has been going on for more than a day, ideally he would see a veterinarian now.
If that isn't possible for whatever reason there are some things we can try at home, but if he isn't responding quickly he should see a veterinarian promptly.
If he has any vomiting or his appetite seems less to try and settle her stomach you can give either:
1) Pepcid ac (famotidine) at a dose of one quarter of a 10mg tablet per 5 to 10 pounds of body weight every 12 hours
2) Prilosec (omeprazole) at a dose of one quarter of a 20mg tablet per 10 to 20 pounds of body weight every 24 hours
These are acid reducers and may help him feel less nauseous and hopefully improve his appetite. They are quite safe and can be used for several days if necessary.
Starting now offer a bland diet of 1/3 boiled, minced, white skinless chicken or boiled, lean hamburger and 2/3 boiled, white rice mixed with some low salt chicken or beef broth to make it easy to lap up and swallow and get additional fluids into him. Add 1 teaspoon of canned pumpkin (not pie filling, just pumpkin) to each meal as fiber soothes an irritated colon.
If things go well and he eats the bland diet and his scooting resolves and the mucous is no longer present in his stools then feed him the bland diet for 3 to 4 days then slowly start to mix back in his regular puppy food, a little more at each meal. It should take about 5 to 7 days to slowly convert him back to her regular diet.
If he continues to have a decreased appetite even with the acid reducers, runs a fever (more than 103F rectally), or has a lower than normal temperature (less than 99F), has a tense painful belly, or if he refuses to eat he should see a veterinarian for an examination, diagnostics, and supportive care.
Even if he seems to improve ideally you should have his veterinarian check at least a couple fresh stool samples too for parasites as parasite eggs/cysts commonly cause mucous in the stools, and are shed intermittently. They may be picked up on the second sample or third test even if the first is negative.
Please let me know if you have any further questions.