Unprovoked bite

I've had a Jack Russel/Beagle for two years now. He's very good with people but bad with other animals. Recently he was laying next to my room mate (that the dog really likes, and has lived with for three months) when he bit him hard in the neck completely unprovoked. It's really unsettling, the dog has never showed any sort of aggression before this.

The only thing I can think of that might have caused this was a week earlier, my room mate tried to take a bone out of his mouth and he growled and snapped, ever since then he has periodically growled at him for no reason (like he'll be sitting on his lap and just start to growl at him), and now the attack.

Would a dog really hold a grudge over the bone thing for over a week? And what woud cause him to get aggressive so randomly?

For unexpected aggression, your first step should always be a vet check to rule out pain or other health issues that may cause the dog to be more sensitive than normal.

I agree a thorough vet work-up is in order.

I also would like to know more details - how did the roommate try to take the bone, what did the roommate do when the dog growled at him. What was the roommate doing in the moments before the dog bit him on the neck, what was the dog doing?

There are a lot of signals dogs give off that many of us are completely unaware of.

I took the dog into the vet and he was fine. The vet said that it is most likely a dominance issue.

He said that my room mate trying to take the bone and backing off when the dog growled showed the dog that he was in control, and that my room mate was underneath him. He also said that now, in the dog's mind, when he's with my room mate and wants to be alone, instead of knowing he needs to go away, he believes in his mind that it is my room mate's job to leave. So he growled, and even my room mate making eye contact could've been taken as a challenge from the dog and caused the attack.

The vet recommended some training, and since that's something I can't afford at the moment, he said we should work on establishing dominance in simple ways like not giving him attention when he begs for it, not letting him sleep in or be on the beds, and not let him on the furniture with us.

It's a bummer because it was his first bite ever, and I really loved having him in bed with me at night, or watching tv on my lap, but I understand that it's something that has to be done to ensure that nothing like this ever happens again.

Take a look at the sticky about dominance in domestic dogs.

It's extremely, extremely unlikely your dog was trying to "challenge" your roommate for a dominant position (and I wouldn't trust behavioral advice coming from a vet unless they're a veterinary behaviorist). He's likely frightened of your roommate because of your roommate trying to act "dominate" over the dog.

There are a lot of links on this website on successful teaching a dog not to resource guard, and it sounds like your roommate has been approaching your dog's resource guarding inappropriately, causing your dog to be stressed and fearful of your roommate.

I doubt it's a "dominance" problem. By that I mean, it's not going to go away just because you stop letting your dog be pushy. A lot of people think that if you start doing NILIF or you start doing "dominance displays" that this will somehow teach your dog to stop all his bad behaviors. While NILIF (basically having your dog follow commands before he gets anything he wants) may teach the dog impulse control and gives the dog lots of practice with commands, it isn't going to suddenly stop his "bad" behaviors. You need to target those problems separately. And for the record, your roommate was right by backing off when the dog growled, otherwise he would have gotten bitten THEN. The trick here is finding out exactly what the problem is, what triggered him to bite?


My questions for you...
1. How long had they been on the bed together before the dog bit him?
2. Was the roommate touching the dog when he bit him? (either petting him or just having his body up against him)
3. Were either of them sleeping before the bite?
4. Did your roommate move or shift suddenly right before the bite?


It could be more resource guarding (which is what the bone incident was, he just didn't want to loose something so important to him. Dogs can also guard sleeping places if they think you are going to kick them off/make them move). It could also be that he got spooked while he was sleeping if the roommate suddenly moved, made a noise, or touched him. Plus a lot of dogs can become aggressive if they are bothered when sleeping. If your roommate was asleep he might have done something without even being aware (rolled on him, snored and sounded like he was growling, whatever). It's also possible if your roommate was touching the dog he might just have wanted him to stop and used his teeth to make him. In any case you'll need to know what's causing the problem in order to fix it.

Since he's growling at other times my guess is it's either a resource guarding issue or a "stop touching me" issue (either awake or asleep).

To find out what is upsetting your dog you either need to learn about dog body language or get a behaviorist to evaluate him and tell you what's triggering the aggression. Dogs give lots of warnings before they bite (usually) but many of them are quite subtle. They are frequently called "calming signals" because dogs use them to try and diffuse tension in social situations so that they don't have to get in a fight, they feel you are being threatening and they are trying to make you stop. But if they fail then they'll move on and use more obvious warning signs and aggression. Some examples of calming signals are lip licking (most dogs do this after being hugged, it's one that is easier to notice), repeated yawning (you see this a lot during stressful training sessions), avoiding eye contact, sniffing the ground (to avoid eye contact), "whale eye" where the dog has his head facing away from you but is glancing towards you with his eyes (usually see this right before a bite coupled with a stiff body), tail wagging can also be a calming signal (I see this when people are mad at their dog, people often say the dog must be saying sorry because he slinks over with his tail wagging), and paw lifting (holding one paw off the ground) although I don't see that one too much between a dog and a person, I see it more when a dog is being sniffed in the face by another.


If I were you I'd google "calming signals" and also look at some youtube videos of them. This will help you learn to recognize when your dog is becoming stressed so hopefully you can find out what is triggering the aggression. A trainer would be better, but if you really can't afford one I do understand (we're in the same boat!). I do think keeping the dog off of furniture for the time being is a good idea...however you have to go about it the right way. If you pull the dog off of the couch when he's on it then you'll likely make any guarding much worse (or cause it if it doesn't already exist). I would train him to follow an "off" command using treats as rewards. That way you can remove him from the furniture in a non-confrontational way so that the aggression cannot get worse.

Milo and Maxy have given you good advice.
Not letting your dog on the bed or other furniture is not going to do a thing to resolve this issue, it will simply keep the dog off the furniture

Look in to calming signals, check out some example on youtube, and learn to read your dog and prevent him getting in to the state where he feels he has to bite.

A better bet than 100% preventing your dog from being on the furniture (which I don't think would hurt at all, but it certainly won't resolve the problem) would be to

a) train an "off" command, so your dog reliably gets off the furniture when asked,
and b) view the furniture/cuddling in your lap/etc. as a privilege, meaning ask for a command (like "sit" or "down") before the dog is invited up on the furniture as part of NILIF (and not let him on the furniture with you without an invite).