My 5-month puppy is suddenly aggressive to dogs. What can I do now?

Hi and thanks for using Petco Pet Education Center, formerly Petcoach! Sorry to hear about Bruno. When a puppy shows aggression, I immediately advise neutering him to remove the male hormone-driven behaviors. I would advise taking him to your veterinarian for their opinion also. He may have some medical reason for his sudden onset of aggression. Your vet can gather a history, perform an exam and then offer a diagnostic/treatment plan based on their findings. Possible tests include fecal/blood/urine tests and x-rays to look for underlying medical problems that could cause aggression. If a behavioral problem is suspected, then neutering, behavior modification, and drug therapy can be tried. I wish you good luck with Bruno

Canine aggression is a complex behavior as it can stem from dominance, possessiveness, fear, anxiety, resource guarding or a combination. Most people are not familiar with reading canine body language and training. Because of this, I recommend to work with a professional trainer. Researching on your own will also be helpful. Familiarizing yourself with canine body language and dog training can help you to recognize what your pet is trying to say. You can find many books written on the topic and there is a trainer named Victoria Stilwell who I think is particularly helpful. Certainly male dogs who are not neutered are more prone to fighting and aggression. Neutering him may help but it will not likely solve all the problems. Best of luck.

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.

I am very sorry to hear about Bandit. This is a scary situation if Bandit is truly giving no warning prior to his aggressive outbursts. There may be subtle changes in his behavior that are difficult to pick up on without having observed aggressive dogs in the past. Neutering may help decrease his aggression toward other dogs but truly with unpredictable aggression like this a consultation with a veterinary behaviorist is recommended. They can discuss Bandit with you in depth, examine him and observe him in different situations and come up with a training plan to help you manage him (or they may advise he not be around other dogs if they feel his behavior is too unpredictable). I would talk to Bandit's veterinarian to find out about veterinary behaviorists in your area.

While neutering may be of some help if he is old enough for the surgery, there is no guarantee that it will solve your problem. This sounds more like an imbalance in the relationship between you and your dog. I would have him checked by the vet to be certain that this behavior is not being caused by a medical problem. If Blondi is physically healthy, you can ask for a referral to a behavior specialist (not just a dog trainer!). You are also welcome to click on the prompt to initiate a consult and I can be of assistance, though it is easier to work with the dog on site.

Now is the best time to neuter them both. Neutered males are more docile and make better pets. When they reach sexual maturity at around 6 months and their hormones go into full swing so to speak, they may act aggressive toward other males and want to become dominant in the household. If you wait too long, neutering will not help. I suggest neutering all dog sin the house as soon as possible, then the hormones will die down in a few weeks. At this time, implement a training program with a trainer or by doing some research. The behavior will most likely get better, but that is not definite. Neutering with combined training is your best plan to change his behavior. .

I'm sorry that you're having this problem with Cssh! Aggression issues between dogs can be very complex, so without being able to actually meet him in person and observe his interactions with the other dogs, it's very difficult to say what might be causing this. Some dogs simply don't get along well with "new" dogs once they have grown out of their puppy stage - this could well be the case with your dog, since he's about 6-7 months old now. This isn't necessarily abnormal, but it may mean that your dog is not a good candidate for casual socializing with strange dogs. If you want to try and get a better idea of what may be causing Cssh's aggressive behavior and see if anything can be done to improve it, I would recommend making an appointment with a veterinary behaviorist - he/she can evaluate your dog in person and help you understand exactly what is happening. If needed, they can also help you put together a detailed plan to work on the problem. Your veterinarian should be able to find out where your nearest veterinary behaviorist is located, and set up a referral for you if you wish. In the meantime, I would recommend not allowing Cssh to interact with any dogs that he doesn't already know and like since there is a significant risk that he will continue to behave aggressively, which could cause injury to him or other dog.