Petco Text Logo
Petco Pet Logo
  • Two Easy Ways to Start Earning Rewards!

    rewards header
    Become a member today!
    Members-only pricing and offers, personalized care notifications, Vital Care points back on every purchase and more!
    Petco Pay LogoBecome a credit card member today!

    Earn 2X Pals Rewards points at Petco
    when you use Petco Pay!

    APPLY NOW
    Learn More About Petco Pay Benefits

Why is my dog suddenly attacking other dogs after introduction?

Updated on September 23rd, 2025

Pet's info: Dog | Yorkshire Terrier | Male | neutered | 1 year old | 15 lbs

My dog has been near a dog since he was born, and he’s been perfectly fine. Today he was slowly introduced to my friends dogs, and whenever one of her dogs was in the room he’d run and try to attack him. I’ll grab him and tell him no and put him in his cage for a few minutes but he will still do it. He’s always been shy and has never even had the courage to attack me. What is happening?

1 Answer

Most Helpful Answer

Dr. Elizabeth

Answered By Dr. Elizabeth

Veterinarian

Published on April 27th, 2019

I hate to hear that about Archie. Unfortunately it's impossible to know why he is doing this without analyzing his body language. Canine aggression is a complex behavior as it can stem from dominance, possessiveness, fear, anxiety, resource guarding or a combination. Unless you are very familiar with reading canine body language and training, I recommend to work with a professional trainer to achieve best rests.
Certainly familiarizing yourself with canine body language and dog training can help you to recognize what your pet is trying to say before a bite happens. You can find many books written on the topic.
Once you understand the underlying cause, appropriate behavior modification can begin. Best of luck.
Vote Icon1Pet Parents found this answer helpful

Smart Picks for Smart Questions

Have A Vet Question?

Book an appointment with the pros – our expert vets are here to help.

Share

Styled arrow button