If he hasn't had any vomiting, is just swollen and doesn't seem to be in pain, it is must likely he just has a little bit of bloat and gas due to the Iam's puppy food. Also be sure that he is up to date with worm control as this can cause abdominal swelling (albeit not so suddenly). You will need to keep a close eye on him tonight as it is a little worrying he has had diarrhea for the last couple of days. If he develops vomiting or seems painful tonight then you really need to get him to your local ER Vet tonight if you can. If he makes it through the night ok, it would be a good idea to get him to your regular Vet tomorrow if you can. Please keep a close eye on his mucus membranes, capillary refill time and respiratory rate tonight as follows:
Mucus membranes - flip his lip and look at the color of his gums. They should maintain a nice salmon pink color. Get him to the emergency Vet if they appeal white or very pale pink, or if they are a dark deep red color.
Capillary Refill time - this measures blood perfusion and test this by putting your thumb on his gum to apply pressure. After you release your thumb you will see the gum blanch. Capillary refill time is the amount of time it takes (in seconds) for the gum to return to a healthy pink color from the blanced white color. If 2 seconds or less don't worry - if it is taking significantly more time, again - off to the emergency Vet.
Respiratory Rate - if he is continuously panting throughout the night this is a sign of shock and or pain and a signal for a trip to the emergency Vet.
There are a few things that could be going on here other than just being bloated, so this is why it is important to keep an eye on him. This could include anything from a partial chronic obstruction, a full complete obstruction or even something like an intersucception where the bowel telescopes in on itself. Hopefully the cause for your boy's diarrhea is just diet related or gastroenteritis rather than something infectious like Parvo!
Best of luck with your Chihuahua puppy and please let me know how you get on. Again - keep a close eye on him and take him off to the emergency Vet if you are worried tonight otherwise straight to your regular Vet in the morning. Be sure to give your dog a pat and a cuddle from me and please reply if you need further info.
Thank you and please now click ACCEPT.
Dr M D Edwards