The phrase "dog stomach" refers to having a very strong or capable stomach, like a dog. It means someone can eat a lot or handle eating things that might make others feel sick. Full definition
To keep your canine companion in good health, it helps to know the signs of dog stomach problems and what you can do when they happen. (pets.webmd.com)
The veterinarian will check for any abdominal or dog stomach pain, changes in the muscles around the abdomen, gas and fluid accumulation in the abdomen. (dog-health-guide.org)
Dog stomach tumors are usually malignant and spread to areas such as the liver, lymph nodes and lungs. (dog-health-guide.org)