[Kimba’s Mom]

Hi, I’m desperately seeking advice on how to stop our puppy from continuing to be aggressive to her older sister. Last evening our 11 month bull mastiff attacked our 5 year old Rottweiler. We brought Kimba (mastiff) home as a puppy and she has been raised with the Rottweiler. They haven’t had any issues until last night when the mastiff attacked the Rottweiler, the Mastiff had shown signs of guarding and edgy but nothing we seem to do would stop it. it took 3 adults to get her off the Rottweiler, and I ended up getting bit by the Rottweiler trying to defend herself.
They have been separated in the house and I purchased a muzzle this morning. We tried to bring them together again, with the puppy muzzled and on a leash, but she immediately attacked the Rottweiler again. I will make a vet apt tomorrow to see if she is suffering from a health issue, but until then, I’m looking for advice on why this suddenly happened and most importantly to prevent it from happening again. We are devastated and the thoughts of losing either baby is breaking our hearts. We love them both so much

 

[BKaymuttleycrew]

I'm very glad to hear that you're making a vet appointment to check for medical issues, but... at the end of the day you have two large (FEMALE) guardian breeds who are known for being 'highly selective' on the dog sociability scale. Sadly, at 11 months, the younger dog is coming into her own as far as adult temperament goes, and at 5 years of age, your Rott is slowing down considerably. They might never, ever again get along. If I were you, I'd resign myself to a life of 'crate & rotate' for the duration of the older dog's life. Will this be a P.I.T.A. for the next few years? Yeah, probably. But.... The alternative is even more unsettling.

 

[storyist]

I did the absolute separation thing for years with my two Rottweiler bitches. They were fine until the younger one's puppy license ran out, and then the older one was determined to kill her. It was not a great way to live. I kept 3 barriers between them at all times and was fortunate at that because neither one was the sort to challenge a barrier. Even so, I have to be honest, faced with the same situation again, I'd rehome the younger one.

I prefer female dogs, have always gotten females, and my current puppy is a male for no other reason than I still have a female Rottweiler and don't want to be in the same situation again.

You have my sympathy. I hope you work this out in a way you can be satisfied with, but you can be sure that ever letting these two dogs together again would be dangerous and will never work.

 

[DaySleepers]

I agree with the others - screening for medical issues is a good idea just in case, but you need to prepare for the fact that this is same sex aggression (SSA), which is extremely difficult to truly eliminate. If you want to work on it, I highly recommend looking for a trainer or behaviorist with experience in aggression/SSA behaviors, ideally someone who has some degree of formal education in animal behavior or certification through a third party like the Certification Council for Professional Dog Trainers or the International Association of Animal Behavior Consultants.

Even with professional help, I would assume these will never be dogs who can be together unsupervised, and I would not allow them contact at all until you have a professional present to help monitor and manage the situation safely. Even with professional help, they may never tolerate one another and need lifelong 'crate and rotate' type confinement if you want to keep both. It's absolutely possible for either dog to cause serious injury to each other or any human who tries to intervene in a fight, so preventing the fights is extremely important. It's an awful situation to be in, and my heart goes out to you.

 

[3GSD4IPO]

In my opinion these two females can never be together again. Separate forever.

There is a saying:
Males will fight for breeding rights.
Bitches will fight fir BREATHING rights.

Bitches will fight until one dies or they are both so badly injured they must be euthanized. As you note, you also can get badly injured in the melee.

I had an older German Shepherd spayed bitch. I brought in a female puppy that I trained to IPO 3 and FH 1 in tracking. I retired her at age 5 and wanted her to be a house dog. However, with the older bitch in residence I rotated the two in the house until I found an absolutely GREAT retirement home for her (and should anything not work out there I would take her back in a heartbeat). They never fought because I never allowed them together.

If you keep both dogs you will have to be ever vigilant that they never ever get together again.

 

[Barktasticbentlee]

As you know I'm sure, you should be the leader of the pack, a lot of what a dog will do is what you either allow or they perceive you to allow them to do. That being said, I agree with the others in that sometimes 2 dogs simply can not coexist. When it comes to fighting mother nature & in this case animal instincts man does not win. It's a terrible situation as just knowing myself I would not want to give up either pup. But that being said at 11 months the puppy will form a strong bond with a new owner. I would hate to be in your shoes but if I could not keep them separated I'd keep my 5yr old simply bc she has built a life with you. I wish you luck and even more so I wish I had a magic answer for you that would allow you to keep both pups and have them live together peacefully.

 

[Toedtoes]

I have had multiple female dogs in my home and never had a problem. That being said, they were always spayed and did not have resource or people guarding issues. When my dad got a female show akita, she was very aggressive and pushy with my female dog. His dog was not spayed and female akitas tend to be much more prey oriented and resource guarding than other breeds. I couldn't bring my dogs over to visit while she was there - which was heartbreaking because his male was the most beloved Uncle Akita to my dogs. It was a relief when my dad chose to rehome her with the help of the breeder (after she had escaped the yard, ran into the neighbor's house and killed their 20 year old cat on their bed). She ended up as an only dog with a great owner who could work with her issues, and my dad no longer had to feel guilty and stress over a dog that just didn't fit in his life.

With a rottie and a mastiff, I would not do it. First, as mentioned, they are both guarding/protection breeds. They are not pack dogs like hounds, etc. Second, they are both very big dogs and, as you found out, it will be very difficult to break up a fight.

If you really want to try to make this work, I would seek a professional who uses positive training methods only. But I would be prepared for it to not work out.

If I had to keep my dogs separated for years, I would rehome one. To me, it is not fair to either the dogs or you to do the separation routine. And that one time you slip up and forget to make sure the door was properly shut, etc, you could face a horrific ending.