My last dog and present one had the same thing, both Collies.
Does it sound as though a war is going on in the tummy?
I could hear the LOUD gurgling sounds from several feet away but
I'm sure it's because they are large dogs too I don't know if you could
hear it as loudly in a smaller dog.

Anyway, when he is having these loud tummy sounds he doesn't eat much
nor drink but his attitude and spirit is just as happy as ever, he never looked
or acted like he was sick. Then eventually he would spit up this yellow foamy
substance and the noises would stop. This started in May and he's had about
3 episodes. I took him to the vet with the one episode in May, the vet kept
him in the office for 5 hours..........needless to say she never heard a sound
nor did he spit up. Then in June he did it again, so I took him to another vet
and he said my dog had a case of the Mid Ohio Valley "crud". People around
here have many allergies and are prone to SEVERE sinus infections.

In a nutshell the vet said he'd seen this many times and the dog is
getting a small sinus infection and he's swallowing the phlegm and it upsets
his tummy then he will spit it up. The vet gave antibiotics and a pill for
nausea and my dog was fine ever since then, not a sound since. My previous
dog had these same symtoms at the same time of year (April - June) every
year and my vet always said "maybe he had a food allergy". I never did
think so. The vet that diagnosed this said that SOME dogs around here
do get this and some do not, just like some people around here get what is
called "the crud" and some do not, I happen NOT to suffer from any of it
though.

Where do you live? Do you feed yogurt regularly. I now feed him yogurt
everyday (Plain yogurt) he likes it and it's really good for them lots of good
flora and fauna as they say. It's good for the whole intestinal tract.
Let me know if you find out anything more about what causes your dog
to have these loud gurgling sounds, I know just what you are talking about.
At first MY vet looked at me like I was out of my mind and the next vet
who had been in practice about 20 years longer than mine was nodding his
head affirmitively as I was describing to him the symtoms like he'd heard it
a thousand times.