[Ellie May]

I would use the RC until he feels better.
The food has to be converted to a dry matter basis to know how much protein it contains. When the water is taken out, it would be much higher than 8%.
I wouldn't want to give pork either but he really does need an intestinal-friendly diet if it is gastritis. If he doesn't do well on it, you can always go back to chcken and rice.