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Aggressive dog after new puppy--help!
tnoliv posted:
My 5-year-old chihuahua is not very pleased with my choice to get a miniature australian shepherd puppy. I've had the puppy for 6 or 7 weeks, and my chihuahua hasn't shown much interest, apart from growling at her when she gets too close or chasing her down when she nips at him (when she tries to herd him).

However, while my chihuahua looks like he might be getting used to the puppy, he's started to direct his anger completely toward me. I know he's upset with me for bringing a new dog into the house after he's been #1 for so long, but it's gotten to the point where he bites (or tries to bite) me every time I pick him up. He snarls at me when I get near, and he no longer wants to eat or go outside for the bathroom. Most days, he barely leaves his crate. I know this is a common problem, and I expected some sadness, but I'm incredibly bothered by his anger and hostility toward me, particularly because he's his old self around other people who he's familiar with.

What can I do to let him know I love him as much as ever but won't tolerate his aggression? I miss having a dog who didn't try to bite me every time I get near him!
d_caitlin responded:
First of all, don't take it personally! You can't feel bad or guilty and help your dog at the same time. He can feel that negative energy and it may contribute to his bad attitude.
It's hard not to associate human emotions with dogs, but he's not like the older brother that tells his mom to take the baby back to the hospital. All he knows is there's a new member of the pack and this new member doesn't know the rules yet, so he's taking it upon himself to teach them. That is completely normal, though he may be a little too aggressive when he does it. In which case, you need to be the one who sets the rules and enforces them.
Right now, your chihuahua is the king of the house and everyone in it lives under his rule. He's the enforcer. Dogs are usually ill-suited to lead the house, so he's not very good at it and is getting aggressive toward you as well. He needs to know you are in charge. You have to take back control- and he won't take it personally either. You'll still love him and he'll still know it, but he has to listen to you.
Disagree whenever he shows aggression- whether that's with a noise, a snap of your fingers...etc. Don't back down from your dog, follow through, and set boundaries. Always be calm when you do this, but not a pushover. See if obedience works, using treats or whatever he likes.
I hope that helps a bit. There are a few discussions like this that have more suggestions too. Good luck!


William Draper, DVM, better known as "Dr. Will," is a well-known small animal practitioner in the Atlanta, GA area. He grew up in Inglewood,...More

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