I am sorry Jack has this trouble. Check inside his mouth for a stuck item, sore, bad or broken tooth or any abnormalities. Look under tongue,roof, cheek pouches and between lips and teeth. If you do not see anything he may have swallowed a sharp item like an earring post, have a sore throat, bad tooth or be nauseated.
Give him two drops of honey to sooth his throat.
Pick up all dry food. Offer him pate canned cat food or human baby food chicken with no onion or garlic.
If he will not eat or continues to paw at his throat a vet should examine his mouth and do a barium xray to ascertain the issue.
Please let me know what is found and how Jack is doing.
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