Just got 3 year old male and female,

Question
QUESTION: Hello, We just got a 3 year old Male and Female Boxer, to add to our 9 month old boxer female, and our 100 pound pit/mix. the history on the new boxer is they have been in a cage all their lives, they never where let out and she has just had a littler of pups that are 7 weeks old, the pups have been sold by the previous owner and she is back in heat i think he might have breed her once more while the p.o. still had her.
        I told you all this because the background i think will be important to the question.
    the new male growls at every thing! jumped on our pit and got the crap bit out of him. we are trying to get all used to each other the female is doing good and gets along with every one. but the male dose not like even my lil boxer female what can i do, now the male is in a crate and only gets out when all dogs are put up or he has a muzzle on. the pit will live him alone but the boxer trys to start it every time, thanks

ANSWER: It sounds like you are having a very big problem with dominance.  Some other things to take into consideration at this point which you have not mentioned... Are these dogs neutered/spayed?  If the new male is not neutered already at his age this could be causing a lot of issues.  However, from what you describe about their pasts, it seems they suffered some unfortunate abuse.  I see this a lot in the rescue i volunteer for.  Dogs kept in cages all their lives often have many issues resulting from this.  If this other female boxer is the only companion this male has had during his lifetime, it seems only natural to him to distrust any other dogs.

At this point is is trying to be the boss of the house.  He is trying to dominate your 9 month old and your pit/mix, which clearly the pit is not appreciating.  While it is never to late to train a dog, unfortunately at the already adult age of 3 it becomes much more difficult.  I suggest seeking the help of a behaviorist/trainer in order to have your new male evaluated.  His issues may be trainable, but there is also the possibility his past treatment has permanently affected his behavior.

For now, i would suggest keeping a close eye.  Keep a squirt bottle or shaker can, can with pennies or anything that will make a jolting noise, keep these nearby in case a fight starts.  Take note of body language.  Do they stare at each other?  Are their tails standing up straight? Dogs should never have a 'stare down'.  Normally dogs will catch eyes and the submissive will look away shortly.  If you have two dogs doing the opposite they are fighting for dominance.  Watch their behavior closely, if you see your male boxer instigating and trying to pick a fight, immediately let him know you are boss, and reprimand him and place him in another room.  Do not let him take control of the situation, if he does he is making himself leader of the house, and this is not what you want.

In the short run, all you can do is take steps to avoid a dangerous situation, and continue to train/correct his bad behavior.  Contact a behaviorist or trainer as soon as you can in order to have your boxer evaluated.  In some extreme cases, past experiences just affect a dog to the point where that behavior is so ingrained in their mind.  With 2 dogs, and one of them only 9 months old in your household, it may also be something to consider that this is just not the time to take on such a troubled dog.

---------- FOLLOW-UP ----------

QUESTION: Ok, Thanks for your answer, a little more that has happened. Just now we have come a long way, had them all 4 in the room with us things where going good,, i was petting the male boxer ( who has not tried to fight or pick a fight since i last wrought you. it is now the pit) when the pit jumped on him, it took me and Bubby to pull the pit off, the boxer has more bite wounds on him, the boxer's are doing good, and are becoming happier each time we play with them. The male no longer try to snap at my female he is just a happy go lucky boxer. i think we are going to have to find the pit a new home. i was scared that he would have took a chunk out of my let if the fight went on a little longer. do you think that it would be ok to find him a new home? he is a rescue as well the P.O never feed him he almost starved to death 5 times. He is healthy 107 pounds. kind of skinny. when we got him he was 46 pounds! i hate to do this but what about the kids or my dog?

Answer
Okay...now you have me a tad confused.  Why would you get rid of a dog that you had to begin with?  As per what you said, the pit was not like this before you got two additional boxers.  You said he was fine with the boxer but the boxer would not leave him alone.

Whenever you are introducing a new dog into your family, it is VERY important to not ignore your original k9 family members.  The fact that the pit is now acting out seems mostly out of jealousy.  The experience you described is classic jealousy.  You were petting the boxer, a dog who has only been in your home for a short time, and the pit was clearly jealous and attacked him.  Of course, with a dog breed such as the pit-bull an 'attack' is much more dangerous.  While pit-bull's get a bad rap, they are normally very sweet and loyal dogs unless raised differently.  However, once they have gotten into a pretty vicious fight, it is much more common that it will happen again.

The fact that you have children, this really complicates the situation.  You need to sit down and decide what is best for their safety.  If you feel the pit has become too dangerous, than please find a safe and loving home for him.  Do not dump him in a kill shelter where he will most likely be euthanized.

I hope that everything works out will for your new boxers and your family.  However, in the future i suggest evaluating whether or not your dogs and family are ready for additional members before you get them.  Good luck!