Friend, when we see vomiting of undigested food it is called "regurgitation" as the food has not been digested. There are many possible causes for regurgitation. It will be difficult for me to determine the exact underlying cause without a hands on examination and some testing. But, possible causes are: Esophagus disorders (megaesophagus, strictures, parasites), gastritis, tumors
or even part of a systemic disease.
As far as the increase in breathing it can be related to any of the above conditions. Or, he may have a totally different problem like: Pain from his hips, heart/lung disease, etc.
I understand it is difficult taking him to see family vet. But, at this stage, I would highly recommend you consider having him checked by your family veterinarian for xrays and blood work as initial screening test to determine the exact underlying cause. You can speak to your vet about dispensing a tranquilizer to be given at home. Or, your vet can sedate him in the clinic. In the meantime, this is what you can do:
1- Divide his meal to smaller amounts 4-6 times a day. Add some water to make it as loose as possible.
2- Raise his eating bowl on to a small stool to force him to raise his head while he eats.
3- Follow up with family veterinarian.
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