Help on abnormal dog behavioral issue?

My first thought is that there's something physically wrong, some medical issue. He's acting as if he could be in pain, or at least uncomfortable. If it was only at the groomers' that he didn't act like himself, I'd say that something might have happened there, but since he's not acting like himself at home either and a couple of days after the grooming, I think it's something else. I'd take him to the vet for a check-up just in case, and watch him more than usual so you can spot any behaviours that aren't normal for him.

It's possible that you're running into training issues here, even though it sounds like you've done things right so far. Dogs do change as they mature, and can have what seems to be a personality change but is really just becoming adult rather than puppy. They tend to get more assertive, and you might have to change some of what you do to keep him a sociable and well-behaved dog. If nothing shows up with the vet check, I'd consult a trainer. Are you sure there's nothing that's happened lately that could be making him feel anxious or insecure? Any change in the household, anything different than before in the dog's life, any incident with another dog?

Where do you get your dog groomed at? I am a dog groomer and if you went to petsmart or petco there is a chance they miss treated your dog. I work at a small grooming place. At bigger places such as petsmart and petco, which i used to work at petsmart, they do not have enough time to work with your dog and be nice to them. There could of been a chance your dog did something annoying to the groomer and the groomer got mad at him. You need to talk to your groomer and ask them what he did wrong and see from there. It all really depends on where you get your dog groomed at though. But ask the groomer what he did wrong to be bad that time around. If they say biting and you know he doesn't bite they might be lying to cover up them maybe having a bad day and your dog was just being annoying and the groomer yelled at your dog and mistreated him.

They will never have puppies. And that is the only side effect I've ever encountered with neutering or spaying the dogs I've had. When you decide to have this operation on your pet (and it is a responsible act to do) find a damn good veterinarian to do the job. Remember these animals are dependant on you for everything, they put their complete trust in you so a few extra dollars on quality health care should not be an issue with any pet owner.

Sometimes, sudden aggression is an early hint of an oncoming medical problem or an injury that may have gone unnoticed. That being said, changes in behavior should always be monitored to see if they go away or worsen.

I recently answered a question about a suddenly aggressive dog who, as it turned out, was actually having seizures. I would highly recommend ruling our medical problems first as you can save you money in the long-run by catching illnesses before they progress and become difficult (and expensive) to treat.

Lollypop is right. You have no idea what that groomer did to your pup. I've heard some horrible things from groomers witnessing cruelty their co-workers were dishing out.

I wouldn't flat out accuse it, but something happened during that cut that upset your dog.

Any time there are inexplicable behavioral changes, the first thing to do is to have a full veterinary exam done. There are many physical things which could result in the kind of changes you note... one of the tick borne diseases, pain, abnormal thyroid function, etc.

something might have traumatized him while at the groomer. dont push him getting back to normal. dont take him to the groomers and just act normal and loving around him. he should get better

And this is why you should stay with your dog when you get him groomed.

Because you dont know what they do while they are working on him.

Poor guy