Usually its because they have added a puppy to their household when they already have an adult dog. The puppy, being a puppy, wants to play. The adult dog might be willing to play, but typically will not want to play as much as the pup does.
I equate the adult dog’s reaction to a child meeting his baby sibling for the first time. His response is NOT going to be “Oh, hey, someone to play with!” Instead, it will be “What?! I wasn’t good enough?? You had to bring that intruder into my house?”
Introductions are important for a smooth beginning towards a long-lasting positive relationship. For more about how to assimilate your new dog into the family, read the blog post The New Guy.
In the first few weeks of becoming a two-dog family, actively supervise the dogs’ play behavior. “Actively” means watch them! Just being in the same room with them while responding to emails is not enough.
WHAT TO LOOK FOR
Alarm bells should go off in your head if you see any of these behaviors:
Dogs will chase each other in play, but one dog might be frantically trying to get away from the other;
One of the dogs is shrieking as if in pain;
One dog has the other one pinned to ground….that dog is struggling to get up and can’t;
The tone of the growling changes into what can only be described as “serious, focused and fierce;”
One dog completely avoids engaging with the other dog.
Keep in mind that dogs in play will typically make noises that we might interpret as threatening or aggressive but are actually quite normal. For example, there might be lots of growling, barking, or other vocalization.
HOW TO SEPARATE THE DOGS
For any of the above behaviors, consider separating the dogs to allow them to cool down and give them a break from each other. DO NOT grab them by the collars to pull them apart! This is how owners get bitten, however unintentional it might be.
Clap loudly or squeak a toy to create a noisy diversion.
Throw a heavy blanket over the dogs.
Outside, dowsing a bucket of water on the dogs is pretty effective.
WHEN TO CALL FOR HELP
If your dogs can’t seem to play together without it escalating into a fight, or the dogs growl or lunge or snap at each other whenever they are in the same room together, if one dog repeatedly attacks the other, you need the assistance of a professional dog trainer/behaviorist. This is called Sibling Rivalry – read the blog post No One Saw It Coming if you are worried that your dogs just don’t get along. Most important, though, is don’t try to fix this on your own. Its just too risky.
WHAT TO DO IN THE MEANTIME
Keep the dogs in separate rooms or areas of the house. If that’s not feasible, use pens or crates to keep them apart. It almost goes without saying that you should be feeding them separately. If they absolutely have to be together, keep them leashed and restrained by responsible adults.
Be aware of the triggers that can cause two dogs to fight: one dog is on the furniture and the other one isn’t, one dog is getting affection from a family member, dogs are passing through a door or a hallway at the same time. Sometimes its just the way one dog looks at the other that will set them off.
NOTE: Everyone has a their own level of tolerance with dogs playing. Some people are constantly concerned and want to stop the play after just a few minutes. Others figure the dogs will work their differences out, and so almost never intervene. A professional trainer can observe the dogs’ play and let you know what is appropriate and what isn’t.