Thanks for the question. Bloat and indigestion are very similar. Indigestion is basically an upset stomach (gastritis). This can occur from a dog eating food that doesn't agree with them or from too much stomach acid production. It is generally mild, may be associated with productive vomiting, that subsides over a short period of time. With indigestion the abdomen will not be distended.
Bloat is a build-up of gas in the stomach. Bloat in itself is not generally life threatening. Where we get concerned is when the stomach flips over. We're not sure if the bloat leads to the stomach flipping, or if the stomach flips, then bloat occurs. No matter what happens first, this causes a life threatening condition called gastric dilatation volvulus (GDV). GDV requires immediate emergency intervention or death will occur. Signs of GDV are: distended abdomen, distress, panting, unproductive retching, injected sclera, red gums.I hope this helps.