9 month old agressive pitbull/mastiff mix

by Courtney
(New Jersey)

From Courtney...

I have a 9 month old Pitbull/Mastiff mix and a 3 year old Chihuahua. We got the the puppy when he was 7 weeks old and the 2 have always gotten along well together.

A week ago the puppy attacked my Chihuahua and had her by the neck. He never bit her but almost strangled her. We're not sure at all why or what happened that he would go after her.

Now they are separated, but they cry for each other. I'm too scared to let them be near each other. Why would he have attacked her?

Shannon Says...

Hello Courtney,

Thanks for your question. In any case of aggression, I always recommend getting a professional balanced trainer in your area to give you hands-on help.

Aggression is not something you want to try to solve with trial-and-error on your own.

You've done the right thing by keeping them separated for now. Aggression doesn't usually show itself until the puppy starts to reach physical maturity, between 9 and 12 months old.

Every case is different though, so it's hard for me to give you a definite answer to your question without seeing your puppy.

There are many different factors and stress points that can play into why a dog will bite. While breeding can definitely affect a dog's actions and behaviors (a beagle that barks excessively, a terrier that digs, etc.), I am not one to blame aggression on any specific breed of dog.

If you have not already done so, be sure to obedience train your puppy - up to and including advanced level and off-leash control. This will help to establish you as the dominant one of the household.

Another suggestion is to get yourself a small boat air horn that fits in your hand. Should you run into another situation like that, press and hold the button on the horn for 3 to 5 seconds.

It's very loud, and should startle the puppy out of the behavior, which will give you the opportunity to separate them.

Again, sorry I can't be of more help! Find a trainer near you to help troubleshoot the problem more thoroughly.

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Jan 26, 2013
Pit Bulls
by: Shannon - Precision K9

Thanks for all your comments and discussion. There is definitely a lot of mixed feelings about Pitbulls and other large breeds like this.

As was already mentioned, any dog can be aggressive - and from my experience as a trainer, I have actually seen more aggression in breeds other than Pitbulls (German Shepherds, mixed breeds, Huskies, Schnauzers, Chihuahua, Akitas...). The only difference between aggression in a Pitbull and aggression in a Chihuahua is that the Pitty is a big, muscular dog who can potentially do more damage.

American Pit Bull Terriers came from crossing Bulldogs and Terriers. According to the UKC, "this breed is eager to please and brimming over with enthusiasm. APBTs make excellent family companions and have always been noted for their love of children."

It's powerful and fearless, but really does have a high drive to please his master. APBT used to be a very popular family pet in the US... unfortunately, unfit owners have turned public opinion against them.

The reason Pit Bulls are so popular for illegal dog fighting is not because of their attitude or nature, but because of their size and strength. If you look at the facts, almost all fatal attacks involved Pit Bulls that were raised improperly or trained for fighting.

So yes, you have to take the breed's size and strength into account when choosing a family pet (same goes for any large breed). But more importantly, you need to actively be training and shaping your dog's behaviour from Day 1, regardless of their breed.

Jan 09, 2013
Pitbulls aren't all bad
by: Courtney

That is not true at all. My dog (the previously mentioned Pitbull/Mastiff mix) is fearful/aggressive, but when he come into close contact with any other dog regardless of age or breed or size he will cower down to them.

He is 90lbs and growing. He will bark and act tough, but when the dog comes close enough for my dog to snap, he doesn't. He puts his tail between his legs and cowers. On the other hand my mother has a Pitbull female and she is the absolute sweetest dog. Pits in general will only do what their owner teaches them to do - they live to please, so don't blame them. Blame the humans who made them that way. It's people with this attitude that give them a bad name and cause dogs who deserve a second chance to be put down simply because of their breed.

Jan 07, 2013
9 month old
by: Anonymous

The pitbull, mastiff and other dogs of this nature are very unstable dogs. They are beautiful and protective but you are asking for trouble with this dog and your other dog. I just had a pitbull/mastiff who the owner said was not aggressive in a dog park attack my small puppy dog. I even asked her if her dog was OK with a puppy. She said yes. My dog had 50 stitches in his mouth, 2 broken teeth and a smashed tooth. I am taking the owner to the highest form of the law.

These dogs do not belong in dog parks or near children. I know I am going to hear that any dog can do this but a Pit is different. They DO NOT let go. I love all animals including a pit, but only certain people should have them. They DO NOT like other dogs they don't know. I don't care one anyone says. They can snap at anytime.

Aug 03, 2011
Me too
by: Courtney

I also have a male pitbull mastiff and a male chihuahua/jack russell, and the pitbull/mastiff is also the youngest, but he is not very aggressive towards the chihuahua/jack russell. he is more a mix of aggressive and fearful of other dogs and humans. I have taken him to a professional trainer and even had him neutered, and he is still digressive and fearful. Is there any reason why he acts like that?

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