I had Jethro out today on his long line, practicing voice commands under varying degrees of distraction.

Out on the field, where Skipper was chasing a ball, I was playing with Jethro and tossing toy. I noticed his saliva was kind of thick and slippery when I gave him his treats for successful retrieves.

Not much later, off the field, I had an unexpected chance to work on Focus under distraction. Jethro has been having some problems with random pedestrians, so I have been extra careful to give all passerby a wide berth.

We were just off the sidewalk, where we got caught with people passing on all sides, all lines of escape were blocked. I put Jethro in a Down off to the side and stepped on his leash for insurance. We practiced Focus and clicked and treated while all these people got past us without incident. When I gave him his release and we were walking again, I noticed his mouth had a light, frothy coating of foam around the bottom.

Huh? I know drooling can be a sign of anxiety. Has anyone had this happen to them? Other than being a 2 year old asshat at times, there is nothing else that would indicate anything is wrong. I've just never seen the foam before.

White? No gagging, no symptoms? No drooling? Nothing else since?

To early for toads. They can create the drooling and gagging. Even make a dog toss it's lunch.
One of my dogs has a much thicker and foamy saliva when he does a lot of retrieving. The other is very dry mouthed at all times.
Could be just the nature of that dog.

I hope it is not anything serious. I don't think Canada has any population of Colorado River Toads? I live in Arizona. My immediately fear is always if one of my dogs had gotten in to contact with one of the toads. I have heard horrible stories about dogs who have perished from licking a toad. I don't think it is a grave problem in Canada as it is in AZ. It could be anxiety, or just the nature of your dog (from panting hard).

I hope it is not anything serious. I don't think Canada has any population of Colorado River Toads? I live in Arizona. My immediately fear is always if one of my dogs had gotten in to contact with one of the toads. I have heard horrible stories about dogs who have perished from licking a toad. I don't think it is a grave problem in Canada as it is in AZ. It could be anxiety, or just the nature of your dog (from panting hard).

I hope it is not anything serious. I don't think Canada has any population of Colorado River Toads? I live in Arizona. My immediately fear is always if one of my dogs had gotten in to contact with one of the toads. I have heard horrible stories about dogs who have perished from licking a toad. I don't think it is a grave problem in Canada as it is in AZ. It could be anxiety, or just the nature of your dog (from panting hard).

My dane girl Cassy gets foam around her mouth when she's out exercising hard, and getting treats. It seems to happen more if she finds a puddle and takes a drink. You know Jethro alot better then anyone here, perhaps he was thirsty before you went out for training? Maybe he had alot of water before training and was starting to not feel good?

Check his teeth? See if he has something lodged in between any of them? Or if his teeth have any fractures?
Some dogs drool more if they have a tooth problem.
Tucker was overly drooling/foamy for a day or two, I kept looking in his mouth to see if i could see anything, nothing.
It was bothering me so much that I finally stuck a flashlight in his mouth and felt around and low & behold he had a fragment of his Flexi/chewy bone stuck between his back large molar. I pulled it out and the drooling stopped.

I will check his teeth and make sure nothing is lodged in there. He is otherwise his usual self, no vomiting, diarrhoea, or unusual behaviour.

I think the comment about water intake combined with excitement might be pertinent. He gets very excited just walking on the field, much less playing on it, and abstaining from attacking people/dogs (keeping his charges checked by voice command).

He just passed his two year birthday, so he is still popping up with new ways to push the boundaries. These efforts are generally accompanied with an over-excited state of mind, and it takes real concentration for him to remain calm (or somewhat calm). I think the foam was a combination of ropy saliva, excess drooling, and lip smacking and/or blowing his lips in and out.

Thanks for your comments and suggestions.

Heavy breathing and panting turns saliva into froth or foam.