My male German Shepherd is suddenly aggressive and biting. What to do?

Hi there and thank you for using Petco Pet Education Center, formerly Petcoach. I am sorry to hear that this has happened. This behavior is certainly concerning as you don't want Boston to cause serious harm to your wife or anyone else for that matter. I would recommend taking Boston to a behaviorist for training and other recommendations. There are trainers that will take Boston for several weeks for the training or trainers that will come to your house for in home training. At 4 months of age, this is easier to correct than when he is 4 years old. Now is the time to take action as it is much easier to train a puppy. I hope this helps and for now, please take the necessary precautions and keep Boston away from anyone until he is appropriately trained.

This is very dangerous. I don't have enough information, like your brother's age, to give you a good answer. If your brother is under 10 years old, he may not be mature enough to be around a dog unsupervised. Also, if he is teasing or playing very rough with Shad, he may have taught him this behavior, Or, Shad may be fear aggressive due to poor socialization and is actually afraid of your brother. All of these things are very common. First, you need to neuter your dog so his testosterone is not encouraging this behavior. Secondly, if you can find a veterinary behaviorist in your area, this is the best option. If not, explore this website for help with fear aggressive dogs: www.dogstardaily.com. Good luck.

Thanks for using Petco Pet Education Center, formerly Petcoach! This is certainly possible and recommended but this usually requires in person training by a qualified dog trainer. I recommend you consider contacting a qualified dog trainer to work with you in person. Good luck and have a good day!

I'm wondering if Bruce's mother is spayed - if not it could have something to do with heat cycles. It can be really difficult to pinpoint exactly what has caused a behavior change but I always recommend an exam with a veterinarian first when there is a sudden change to look for a medical problem. Bruce could have pain somewhere or be otherwise ill. If he seems to be in good health your vet can discuss training or refer you to a behaviorist in your area.

Hi, thanks for using Petco Pet Education Center, formerly Petcoach! I am sorry you are going through this. To be brutally honest, this is NOT acceptable behavior from a pet. Regardless of his previous back ground, biting is serious and indicates a serious behavioral problem. Some breeds are more anxious (sadly both husky's and German Shepherds are in that group) and that can lead to aggressiveness. Also dogs reach their social/behavioral maturity around 2-3 years of age. You need professional help if you want to keep this dog and not have an injury happen to you or someone else. He is a liability at this point. I recommend a boarded veterinary behaviorist. Your Vet will likely know ones near you. I wish you the best!

It’s time for obedience training and neutering. He’s coming into his hormones and becoming possessive of the property. Now is the time to work on training him to stop this behavior. Find a good trainer and work with them soon so this does not become a habit. Neutering will reduce the male territorial tendencies also. Thanks for using Petco Pet Education Center, formerly Petcoach to help you care for Rocky.

Neutering can help with aggression, so I strongly recommend getting that done for Regan. But he also needs behavioral training as soon as possible. He needs an expert to work with him on his aggressive behaviors to prevent him from hurting another person. I never recommend owners work with aggressive dogs on their own, so speak to his vet about a recommendation to a professional behavioral expert. I would do this today. Best of luck.