Newly neutured dog mounting and leaving penis out

Question
We got a rescue dog from the humane society 6 weeks (when he got neutured also) and we have been watching my mom's dogs and our dog in non-stop mounting them. We took him away from them in the car today and he had his penis out in full for about 3 hours in the car.  He had it out a little once and awhile before we had the other dogs but now he won't put it away. Do you know why or how to stop this behavior? Thank you Mandi

Answer
I can go 2 ways with this.  First, he is excited and showing you some play behavior that is a bit inappropriate in the situations.  You can teach him an alternate behavior to mounting - like a sit, or fetch or something else.  Showing his penis could be excitement, often dogs do this.  Which may mean he is under socialized so I would recommend a training class.  Look for one that uses positive reinforcement, like a clicker.

Second - there is possibly something wrong after the surgery and he may need a vet check up just to be sure.   This is probably more relevant to the penis being out and not the mounting.

Hard to know for sure which it is when I can see the dog, sorry.