my dogs breath smells like sour milk. is she sick? this is NOT normal for her
Is she vomiting, or having diarrhea? How is her appetite?
everything seems normal
So she is acting like her usual self, in every way?
yes
OK, thanks. I wouldn't worry much, if everything seems normal. Possible causes for sudden bad breath include having chewed on something that smelled bad, such as a piece of trash, or a dead animal, or even fecal matter. Also, dental disease can cause bad breath, but that should show up more gradually, rather than all of a sudden. One other thing that could cause it is anal gland problems, since dogs with these problems tend to lick their own rear end excessively. Other things that could cause bad breath, such as stomach problems, or kidney disease, would cause other symptoms as well, which you've reported is not an issue. I wouldn't worry too much at this point, but if the problem persists, and you're sure that nothing foul is being eaten, I'd recommend having your veterinarian perform a thorough exam of the mouth.