Aggressive behavior from formerly docile dog

Mack is a Rottie we adopted. He is a lovable dog but within a day or two it was obvious he had been abused and neglected by former owners.
We have 4 Dashounds and 2 Boston Terriers. We've had Mack about 7 months now. We introduced him slowly to the rest of the herd. He fit in right away and got along very well with everyone.
The last 3-4 days he has made a point of snapping at the Bostons. Yesterday he pulled one off my lap and dropped him on the floor. I thought he was jealous so took him outside and played a bit. Last night at 2am i woke to a dog fight. The Boston wasnt hurt but he was very scared. I put Mack in the kennel and he grumbled at me. Not growling more like complaining.
Today I tried to keep either him or the Bostons crated all day taking turns in 2 hour sessions. When we were bringing Mack in from outside one of the Bostons(the female this time) was getting a drink and he grabbed her and bit her.
My son grabbed him and yelled at him Bad dog Bad boy and Mack growled at him. Really growled. I was afraid he was going to bite. Mack went into the crate and we are back to 2 hour sessions.
I don't know what to do. I don't want to have him put down but certainly don't want to risk my children or my other dogs. Does anyone have any ideas?

Take a trip to the vet to make sure he isn't injured or sore somewhere.

We have a vet visit scheduled for Monday. On the phone today she suggested fixing him or putting him down. He's been such a nice dog up till now that I hate to put him down without first checking everything.

Obviously he has previously learnt that aggression is the best means of protecting himself and getting what he wants.
He might not have been badly abused to get like this. Just general punishing type treatment that most people wouldn't think was classed as cruelty can be enough to make a dog like this. Take Cesar Millans methods for example and how many times you see him get bitten.

You might find this page helpful. A behaviourist/trainer who does NOT use aversive techniques could help him. Any forceful methods used on this dog are likely to ellicit an aggressive response because this dog has learnt that when people show aggression towards him, he can stop it/prevent it by showing aggression back.
The right training can help him reaslise he doesn't need to show aggression but it's just finding it.

Here's the page btw:
http://www.dogwelfarecampaign.org/be...r-problems.php

If the only two things your vet could suggest is castration or being pts, I think you need to find another one.

Castration isn't likely to resolve anything anyway. This behaviour is learnt, NOT hormonal.

I think you need to address this sooner rather than later.

Do get him neutered, it can't hurt.

Here is the link to the American Pet Dog Trainers site, APDT. This is one group which trains dog trainers, and they use positive reinforcement techniques. All the classes I've taken my flock to are certified by APDT.

http://www.apdt.com/petowners/ts/default.aspx


See if you can find a trainer near you.

One MAJOR reason you need to move quickly: many of these trainers are certified to work with aggressive dogs. NONE will work with a dog which has bitten or nipped a person. So you need to control the situation at home until you can find and start the dog in a training class.

Good luck!

This is entirely new behavior. In the 7 months hes been here he has never growled or snapped at a person or dog until this last week.
We don't discipline our dogs by hurting them. Usually just saying BAD DOG in an angry tone will do the trick. If not then they go in the kennel. the very plain empty boring bad dog kennel with only food and water, no toys. Most times it is a 10-20 min time out.
When they are good they are rewarded with treats, pats, hugs and playtime. All of them including Mack are spoiled. Everyone has their own nap pad in the office. Mack often sleeps in the other office chair pulled up beside me.

You can tell he has been abused because of the way he reacts to certain things. He is terrified of shoes and belts. Just pick up a belt and yelps and runs to his crate. The shoe thing i found by accident when throwing all the kids shows into the front hall from my living room. He was across the room and cried out and ran. He was so scared he peed.

could this be his way of trying to be top dog of the house , i had similar with my 1 female mastiff she would bite over food treats toys and then started trying it with me , shes been put in her place sinse and the behaviours vanished but i know how scarey it is when you have little ones around , its always best to have 1 person top of the house in the dogs eyes as i think it can confuse them .
hope your able to fix things x

How old is Mack?

Please follow Canis-Lupess's advice (and please not Mrspamgoo) and find a reputable, positive reinforcement behaviorist! Just one session with a certified, educated behaviorist will open your eyes to so much. Honestly, we cannot see what is going on, so we can't give you sound advice.

My only advice until finding a behaviorist is to control the situation COMPLETELY, stop the yelling and punishing, destress and make every experience that Mack has around the Bostons (safely seperated/leashed) extremely positive. Give him high value treats every time the Bostons are around and Mack is not reacting poorly to them. Make him see them in a positive light. It could definitely be that Mack isn't feeling well, or something happened that you didn't see, or he's simply coming into maturity and going through a phase. A good behaviorist (after the Vet check up) will tell you for sure.

If this is new behaviour then you should definitely get him checked over by a vet to make sure there isn't some underlying pain or illness causing it

a behavior like this that is So out of the norm.. would call for a vet visit Good luck, I hope all is well!

There are so many possibilities for this "new" behavior. First off... In a house with 6 other smaller breed dogs, why would you NOT have Mack neutered already? Rottie's are loving dogs but they are also physically and emotionally strong dogs. Neutering has strong benefits if it is done at an approptiate age. After the fact the behaviors are learned and it has less of an impact but can still reap rewards in hormonal issues. I am assuming Mack is somewhere around 1 year to 1 1/2 years since you have had him for about 7 months and it sounds like you rescued him. If that is the case, it is still a beneficial idea to have him neutered. His age in and of it's self could explain the change. He could be going through his adolescents and it could be hormonal.

I will say though that I do not know enough from what you wrote to know for sure what is going on and I strongly suggest you do get a dog trainer who has a behavior issues background involve ASAP. From what you do write, I do not lean towards hormonal but more of a reflex response. Since it is only directed at the Bostons, I would think that something happened that you are not aware of that is causing the sudden change in the Rot's behavior.

In any case, you need advise from someone who can see the interaction of the two dogs in question so they can give a more educated analysis of the situation after seeing the dogs interact.

BTW.... I don't know of ANY vet that would want to put a dog down for this kind of behavior unless it was totally out of control and the aggression was constant. If your vet thinks this way, I would seriously look for another vet. Especially if they make this kind of determination just from a phone consult and not seeing the dog in person. :confused: