Two Dogs from Litter Fighting Daily

Mo and Abby were close for years but recently Mo (male dog) will become aggressive and seek Abby out for a growl and then fight. It usually occurs after he has waited for her to eat and then he has eaten. It doesn't always seem to relate to eating though.

It is clear that Mo is the aggressor. I have always thought that Abby was the dominant dog between the two of them over the years. He is generally very submissive.

Should we muzzle both dogs? Mo has actually injured Abby by causing a rip in her eyelid. (an expensive fight) What do we do?


Vet Suggestion for Stopping Aggressive Behavior Between Two Dogs


Hello there,

Any time a dog’s behavior undergoes a significant change, the first thing we need to do is to rule out potential medical causes. It is possible that Mo is in pain, does not feel well, or has a neurologic disorder that is causing him to act out in this way. After a veterinary exam indicates that Mo is otherwise healthy, the focus can shift to improving his behavior. It is also possible that Abby is sick, and this is causing her behavior to change in ways that are stimulating Mo’s latent aggression.

Both dogs should be examined by a veterinarian as soon as is convenient for you.

Since most of the aggression you are witnessing seems to be focused around meals, the simplest short-term fix is to feed the dogs separately. I recommend feeding one of the dogs in a separate room, behind a closed door. Once everyone is done with their meals, pick up the bowls and any stray bits of food and open the door.

Do what you can to avoid any of the other situations that seem to bring about aggressive interactions between the dogs as well. The more times a behavior is repeated, the harder it is to stop.

I don’t recommend muzzling the dogs. Instead, have a couple of comfortable crates in the house where one dog can rest safely while the other has some freedom and play time. Then, reverse who is crated and who is allowed to be out and about.



Best of luck,

Jennifer Coates, DVM