I have a 2 year old pug. I just changed her food about 2 weeks ago and she didn't seem to have a problem with it. She threw up a small amount of liquid the color of her food the first week and that was it. However, this morning she threw up 4 times and a good size amount (probably about 2 ounces.) We fed her the remainder of the bag of food last night which was not much at all, and she seemed like she felt fine when we took her out this morning. I have read a lot of places that pugs tend to get an upset stomach faster than other dogs and it can be caused by heat. We live in VA Beach and it is 75 degrees by 5 am and very humid, could this have something to do with it? She does not have dirreah and no problem peeing. I have noticed though that her poop has been very green lately, there is green stuff in her food (a sort of vegetable) and just figured it was because of that. She seems to be fine now that she has thrown up, and is just laying down in her bed. Her throw up was the color of her food (an orangeish red, but not bloody) and had a watery substance with it (I don't think it was bile because it seemed to have the tint of the throw up itself.) It was also sort of chunky?

Heat usually causes a dog to cut back on the amount it eats. Since there isn't any apparent bowel involvement, I think the food is the guilty party. You may change back, if not to the same stuff, something made by the same company may be more to her system's liking. You did have a good reason for changing, didn't you? I mean, besides the thought that your dog is probably getting 'tired' of the same old stuff?

Dogs don't need a variety of tastes in their food... they eat primarily because they're hungry. But, if you insist on frequent changes of brands, don't make the changeover an overnight event... blend them together gradually over a week or so to give the intestines a chance to adapt to the subtle changes in the basic ingredients in each food. Bacteria in the intestines are a major contributor to digestion and they have favorite starches and sugars they like to work on. Each manufacturer makes, essentially, one basic cereal type food, and then changes the flavor, color, shape, etc. based on product research. Consequently, each brand has a unique make up of starches, sugars, which leads to a complementary host of bacterial types in a dog's intestines. Changing basic food types changes this make up, and may cause digestive upsets as a result of improper bacterial action.

Which, come to think of it, is probably the reason for a dog's sudden change of interest in his usual food... Manufacturers will change the types and amounts of the ingredients due to changing market prices or availability. They keep the nutritional analysis the same, though, with a careful juggling of the ratios of the various ingredients. The list of ingredients on the bag is in the order of overall amount of each ingredient in the food, from the greatest to the least amount. You can juggle things around quite a bit, as long as the ingredients stay in the same basic amounts as stated on the bag.

The green is most likely from the artificial coloring in the food. All dog food is pretty much the same baked cereal, with a khaki color to it. The coloring is for the owner's 'benefit'... it is supposed to make it look more appetizing. That, and the flavor enhancers that most put in it as well. But the coloring is what causes the stains on the carpet from 'accidents' or up-chucks. Since dogs quite often will eat grass, the chlorophyll (green) in the grass will show up in the BM as well, if it makes it that far through the system. Most grass usually causes a dog to vomit shortly after they consume it, unless it is fresh, succulent, tender grass, which usually stays down. And comes out a little green.