Is my neutered dog's aggression normal when a female is in heat?

I see that Romeo isn't neutered. This aggression could be hormonally related, and he's peeing to mark his territory and attacking to protect his territory. I would have him neutered as soon as possible, as that will help with any aggressive behaviors that are related to hormones. Then I would have Romeo seen by a professional behavioral expert. It's very serious that he's bitten you and your brother, and he could bite other people. Aggression isn't something that I ever recommend owners try to work with on their own due to safety issues, it's something that should be left up to an expert. After Romeo is neutered, you can discuss a referral to behavioral expert with your vet.

Thanks for sharing your toe, however since we aren't human doctors there isn't much that can be done for that and you should visit your regular doctor. That said, if this is linked to your dog being in heat, keeping the two separated during her heat cycle may help reduce the behavior and prevent a fight from breaking out. Having your female spayed may also help reduce the aggressive behavior if it is related to her heat cycle as she will no longer have them. If the behavior continues to escalate, keeping the two dogs apart and speaking with a trainer in person is best so that they can address the issue and provide a more tailored plan. Picking up and keeping any and all toys, etc removed during this as well as feeding the dogs separately may also help reduce the behavior as well.

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.

This is a very dangerous situation and depending on the trigger for the aggresion neutering may or may not help. I would not recommend this without an individual visit from a certified behaviorist to explore the triggers and patterns of behavior. Please ensure he is not unsupervised, particularly around children until he can be fully assessed

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.

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

Without being able to observe the behavior, it's impossible to know if this is true aggression or if this is play behavior. True canine aggression is a complex behavior as it can stem from dominance, possessiveness, fear, anxiety, resource guarding or a combination. Unless you are very familiar with reading canine body language and training, 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. Rough play is a completely different behavior and will not generally be affected by neutering. I hope this helps and please feel free to post any additional questions.