Does anyone have advise? Two nights ago my Chevy sounded like he was throwing up but nothing would come out. He dîd seem as him he didn't feel well at the time but as soon as morning came he was back to normal. Now, he did it again tonight about 3 times in a row. His tummy is already round

so it's hard to tell if he's bloated but when I touch it he moans alitte. He eats buffalo blue and as far as I know hasn't gotten into anything else. Has anyone else experienced this?