introducing new dog

So my story is my friend live in Puerto Rico and can't have his Dog, a black Pug he seems to be maybe a year or so old, in the apartments they live in anymore. They contacted me about if anyone could take him and I volunteered obviously. So my friend is taking care of vaccines and see if the dog...

Hello: We adopted a 4 1/2 month old labrador retriever puppy last week he's about 35# pounds. Our 7 year old maltese mix is 20# and not happy. The puppy runs him over and pounces on him. The maltese corrects him by growling and biting, but the puppy backs off for a minute and then continues the...

our chihuahua has always been well behaved around our kids other people and other dogs. no aggression. we got a medium sized four-month-old puppy. she will be large, eventually. she is sweet and well mannered, especially for a pup! chihuahua will not stop growling and attacking her. what can i...