Why is my dog suddenly aggressive, growling, and biting others?

Toby could be in pain and acting more aggressive for that reason. He also may have had a behavior change for an unknown reason that is making him fearful of the other dogs. I’d recommend seeing your vet first to rule out pain or another medical condition since he recently had a decrease in appetite.

Oh dear! That is a worry for sure! It's really important that you don't get hurt, because dog bites can be pretty serious. I would suggest making an appointment with your vet to talk about possibilities. They might be able to link you up with a behaviorist, or dog trainer that could help a lot. There also could be medications that might help. Or, like you said, there could be a medical problem that is upsetting him.

Biting aggressively is a serious concern and a very complicated thing to deal with. Leash aggression can sometimes manifest and be redirected toward the person putting on the leash, however if this suddenly happened out of the blue I'd be concerned. A good first step with any behavioral issues that comes on suddenly is to schedule a vet visit to rule out any issues such as pain or illness. Something wrong such as a slipped disk causing pain in the neck or shoulders may make having Griffy's collar or neck handled painful, causing him to bite. If he checks out healthy, talking with a trainer or behaviorist in person is a good next step. They can work with you on a plan to gradually reintroduce the leash to Griffy through positive experiences (such as giving a treat when you bring out the leash, gradually getting him used to it again, etc) and can observe in person what exactly is going on to better tailor the plan. A veterinary behaviorist can also work on both medical treatment and behavioral treatment at the same time to make things less stressful for both you and Griffy. If he is attempting to break the skin while you put the leash on, refraining from doing so until you've talked to a trainer or behaviorist in person is best. You can find a list of local behaviorists in your area by checking out this link: http://www.dacvb.org/about/member-directory/

Oh dear! I'm sorry to hear that you're having this problem with Onyx. Human-directed aggression in dogs is a complex behavior issue that can have many different causes, so I'm afraid it's difficult to say what might be causing this without a full behavior history and an in-person evaluation. This sounds like a very dangerous situation for you, so if you want to keep Onyx, I would strongly recommend making an appointment with a veterinary behaviorist who can evaluate him in person and help you determine what is causing this behavior. Aggression issues like this can be treatable in many cases with careful management and a good training plan to work on the problem, but this should only be attempted with assistance from a trained professional. You can search for a board-certified veterinary behaviorist in your area here: www.dacvb.org

Since this sounds like a sudden change I would recommend making an appointment with your veterinarian to rule out a medical problem first. It is possible that he is painful somewhere and is reacting this way due to pain. I would try not to pick him up until you can see a vet, or wrap him in a thick towel before picking him up. If he seems healthy, you can then discuss what could be causing this behavior with your vet or your vet could refer you to a local animal behaviorist.

Oh no, I'm so sorry this happened! When dogs who are fearful, this can be a common reaction, as having a human lean over them can be scary and they react by biting. In the future, when giving Toby affection, get down onto his level first. I would recommend having him seen by a professional behavioral expert. This type of fear aggression may be improved with training, and because aggression is a dangerous behavior to work with, it's best left to the professionals. Your vet can give you a recommendation to one. I hope your friend's nose is ok!

I'm sorry to hear Cooper has been acting this way. If this behavior is sudden and new, a good first step is to schedule a visit with your veterinarian. In some cases, underlying pain or illness can cause a dog to change behavior and suddenly lash out when otherwise they were sweet or friendly. Your vet can help determine if this may be the case. If Cooper checks out healthy, I then recommend talking with a trainer or veterinary behaviorist in person as aggression toward people is a very complex and serious issue which requires professional help in person. You can learn more about veterinary behaviorists and find one in your area with this link: https://www.dacvb.org/page/about