What can cause random aggression in a dog?

asked 2018-07-11 20:46:58 -0500

I have this pit/bulldog mix that I frequently sit, but this is the first time I've noticed a slight change in his behavior. This time around he's randomly becoming aggressive when my roommate comes home, or when he sees my cats he will give chase and looks ready to kill them. He's never paid any mind to my roommate before, or my cats, but now he growls and barks loudly at random. One day my roommate comes home--no reaction. Then later in the day, he will go ballistic. I've raised dozens of litters of dogs and trained them, but I've never quite had an issue like this. I dont know what could be triggering him, but its getting to the point where I'm afraid to leave, or even sleep, without the dog locked in a kennel for fear he will hurt my roommate or my cats.

He is very sweet with me, but that seems to be about it. He is a free roaming dog, so being in a kennel is very stressful for him and I don't want to make his stay uncomfortable. I haven't told the owners yet, because they've never told me anything about their dog being aggressive--and I've never seen anything until now--so I'm trying to think of things that might be setting the dog off. Any ideas? I'm in a quiet neighborhood, he gets 4 40min walks, but usually he loves to just lie on the couch with me. He gets fed adequately, and lots of belly rubs. The cats will just be sitting on the bookshelf and he just whines and barks and jumps for them.

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How old is the dog? and is he neutered?

Erica M.'s profile image Erica M.  ( 2018-07-12 16:30:45 -0500 ) edit

Maybe he needs to look at a vet, any medical information, depresion or something like that, if you don't think is that check on youtubd, how to handle an aggressive dog, tip watch the dog whisper video, it would give a tip or two, on how to handle you situation.

Juan B.'s profile image Juan B.  ( 2018-07-13 00:57:18 -0500 ) edit

Your problem is the first sentence in your post. I will not go into detail but go look at stats of dog bite fatalities on dogsbite.org

Cesar M.'s profile image Cesar M.  ( 2018-07-20 01:28:47 -0500 ) edit

I don’t agree it has anything to do with the breed. I have a pit bull and he’s a marshmallow

Ellen L.'s profile image Ellen L.  ( 2018-10-14 14:40:42 -0500 ) edit

aggression comes from all places I found out for my dog it was fear she would lash out at strangers sop I started to cover her eyes while petting in-between her eyes one of her favorite spots it calmed her down and let her know she didn't have to protect me. you can look up all the kinds

Natalie W.'s profile image Natalie W.  ( 2018-10-30 03:26:47 -0500 ) edit

“I haven't told the owners yet, because they've never told me anything about their dog being aggressive...” I am a dog owner. If this was my dog, I would most definitely want to know what was going on with my dog. If anyone reads this, please let the owners know if there is an issue!

Wendy S.'s profile image Wendy S.  ( 2018-11-04 23:38:53 -0500 ) edit

how's his vision? tunnel vision and PRA can cause a dog to become defensive or aggressive when they cannot see clearly, and feel threatened or vulnerable. It seems random- but the behavior can change with light and shadows throughout the day...

Rebecca K.'s profile image Rebecca K.  ( 2018-11-19 02:58:51 -0500 ) edit

Alternatively, w/out seeing dog & observing behavior, it's possible dog has become territorial if he is there frequently enough... Pitts (which are terriers) /Terriers tend to be territorial in general- TELL the owners! changed behavior can be a health issue! = pain. Aggression is a danger to all

Rebecca K.'s profile image Rebecca K.  ( 2018-11-19 03:08:26 -0500 ) edit
<http://p%3EDogsbite.org (p>Dogsbite.org) is not a reputable or factual website. Please do not use it if you want factual, scientific information!!!

Kim H.'s profile image Kim H.  ( 2019-03-02 18:24:20 -0500 ) edit

5 Answers

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answered 2018-10-08 01:19:52 -0500

I think you're seeing a couple of different things here. From frequent boardings, the dog has bonded with you, and is now exhibiting protective behavior.

Secondly, the history of the breeding behind Pit Bulls and the Terrier breeds easily explains why the dog is fascinated with cats. I'm sure if Rex caught the cat, no more cat.

This is an accident waiting to happen. The roommate gets bit, the dog has to be put down, the owners furious because they had no idea.

I'm surprised your roommate hasn't put their foot down yet.

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I agree that the most likely explanation is the dog has bonded with the sitter and is feeling protective. I would still recommend a vet trip just to rule out any possible illnesses. Owners should be told immediately and the sitter should take extra precautions to make sure no one is harmed.

Shelby F.'s profile image Shelby F.  ( 2018-10-17 16:40:23 -0500 ) edit
answered 2018-07-14 22:21:25 -0500

I'd definitely recommend getting him checked for Lyme disease (or any other medical issue). I would just politely inform the owners that Rex seemed like he was having trouble this time around and that he doesn't seem like his usual self. "Usually he's super sweet with my cats and my roommate, but this time he was actually growling and trying to get aggressive with them. I wanted to let you know because I know dogs can have medical problems that make their behavior change, and I wasn't sure if that might be the issue. He was his usual sweet self with me though. I just wanted to keep you posted."

Something like that so it doesn't sound like you're insisting on them getting him checked out, and you're not saying you won't take him again or you're a bad sitter for him, but you're just keeping them informed. He may be having issues with a transition or turmoil at home, changes due to age, pent-up energy, recent negative experiences, or any number of other things. Maybe they've known about these issues or have seen them developing over time and the changes aren't as sudden as they appear. shrug Just my thoughts. I hope they're helpful. Good luck!

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answered 2018-07-12 20:46:33 -0500

It the behavior has changed recently the dog may be ill and need to see a vet.

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answered 2018-10-27 15:52:31 -0500

Well, there are many ways that you can try yourself to train your dog. But if your dog is more aggressive then it is better to call a professional trainer to control the aggressive behavior of your dog.

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answered 2019-03-02 18:27:09 -0500

First...talk to the owners asap!! You should be working with them on this issue. Also , it is a known fact that the referenced dogsbite website is not factual in any sense. Please do not use it if you want facts.

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