Regurgitation vs Vomiting in Dogs
It's important to understand the difference between regurgitation and vomiting. Regurgitation is a passive process. The ingesta that is brought up is undigested and looks like the original food that was eaten. Regurgitation will occur directly after eating.
Vomiting is an active process where you will see your dog's sides heave and its stomach and upper intestinal contents forcefully expulsed. Vomiting occurs hours after eating and the contents can contain yellow bile (from the intestines), liquid or foam (saliva & stomach acid) and chunks (partially digested food). The vomitus also has a funky sour scent to it.
Vomit Colour
Colour is another important component to note in your dog's vomit. In some cases the colour can help to localise or narrow down the possible causes. It's also important to remember that dogs often eat a range of things they shouldn't, which can discolour the vomitus, so it is important to look at the colour of the vomit as just one part of the picture. In some cases, the reason for the vomiting can also be diagnosed by having a close look at the digested material - for example, bits of chewed up toys or foreign objects could signal an intestinal blockage.
Yellow Dog Vomit: Yellow, foamy vomit can indicate the presence of bile, indicating that the vomitus has come from the small intestine, just below the stomach. Just like in humans, bile is produced in the liver, stored in the gallbladder and then released into the duodenum - at the very top of the small intestine. Yellow vomit can be an indication of reflux of this bile, or underlying conditions such as intestinal diseases or liver disease.
Green Dog Vomit: Green vomit can be caused by similar conditions as yellow vomit, however toxins and poisons like rat bait can also turn your dog's vomit green.
Blood in Dog's Vomit: The presence of fresh red blood or digested blood ("coffee grounds" or "dregs") are considered serious complications, and an immediate trip to the vet is necessary. Causes of fresh or partially digested blood in the vomit can include blood clotting problems, ulcers in the gastrointestinal tract, gastritis (inflammation of the stomach), diseases of the oesophagus and bleeding lesions in the mouth.
