4 yr old lab regurgitating food daily

4 year old lab regurgitating good daily. He is otherwise healthy, drinking, eating, toileting and sleeping. We have tried slow feed bowl, raising food bowl up, changing raw to cooked fresh mince and pumpkin and stopping all packet treats. Visited vet twice - they are not concerned said it may be a food allergy. Any help or advice

Hello - I am not convinced that it is a food allergy either.  Indeed, it's possible that your vets may have discussed other possibilities with you, because feeding from a height is one strategy that vets reccommend to help a condition called megaoesophagus.  It may be that, as of yet, there are a few differetials and your vet might need to do some tests in order to figure out which of various causes is producing the symptoms you're seeing. As you are already seeing a vet, it sounds as though you might need a conversation with them. Questions that might help include: Do we agree that my dogs' main symptom is regurgitation, not vomiting? What could be causing this? Are any tests needed or would any tests (radiography or endoscopy, perhaps?) be helpful to get to the bottom of this? What could I do to address the problem in the meantime? I hope that this conversation will help to move the case forward for everyone.

Differentials are the possibilities in the list of things that may be causing a condition. Vets usually investigate / try to rule in or out each of the differentials.  They will often choose the most likely, common or the easiest one to rule out to start with.