Updated On September 23rd, 2025
Pet's info: Dog | Mixed Breed | Female | spayed | 2 years and 10 months old
Hi, so about a month ago i got my hazel and daisy spayed, they always got along and rarely right, now all of the sudden Hazel became really agressive and always wants to fight with daisy, we have to keep them separated, she's never been like this and they grew up together.
2 Answers
Published on August 8th, 2017
I am very sorry to hear that you are experiencing these issues with Hazel and Daisy. I believe a couple of possibilities could be occurring. Though only behaviors that will be affected by spaying are those that are under the influence of female hormones, it could be possible that they are both still undergoing hormonal changes and so they need time to adjust. The hormone changes can take up to a few months to stabilator. When everything is stablized, a dog's temperament, training, and personality, are related to genetics and upbringing, not hormones, so should not be affected. Neutering does not “calm” an excitable dog, and unless a dog is overfed or underexercised, there is no reason for it gain weight or become inactive. The undesired traits which are related to hormones such as sexual behaviours, aggression, and urine marking will change over the course of a few days to a few months. It is also possible that Hazel is possibly not healing well and still experiencing some pain or discomfort. I would try gently palpating her abdomen to see if you get any flinching nor pain reactions. A check-up with the vet to confirm she is not in pain would also be a good idea. Pain can be expressed through changes in mood, which are often outwardly viewed as aggressive behaviour. I hope that is helpful information and I wish you the best of luck with Hazel and Daisy.
1Pet Parents found this answer helpful
Published on October 19th, 2017
Dog to dog aggression is usually a hard problem to fix. It sounds like they might both want to be alpha of your pack.... Hazel might want to be leader, but Daisy keeps re-establishing her leadership with the fights. I highly recommend getting an evaluation by a good dog trainer. There are lots of trainers out there, so I would get a recommendation from your veterinarian to make sure that you get a good. one. A good trainer can evaluate your situation and see if there are subtle signs that will tell them what is going on in your dog's head. In my opinion, Same sex (female to female in your case) dog aggression such as this is extremely hard to solve. I don't believe that it was caused by the spaying, but this is the maturity level that they will start to get worse. If they are littermate- the problem is even larger. Littermate syndrome is real problem in dogs. I am sorry that you are going through this. I would get the evaluation by the trainer and get a behavior plan started. Sometimes behavior plans work, and sometimes the dogs just have to be separated for their own safety. Thank you for reaching out to Petco Pet Education Center, formerly Petcoach!
1Pet Parents found this answer helpful
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