Hi! I have a question about my aunt and uncles dog, Ellie. She is a mixed breed about medium size short hair and around 6 years old. They've had her for many years. We've brought our 7 year old female Brittany spaniel, Dixie out there to play with her for the past few years and they have always gotten along, just a few playful fights. Just a few weeks ago Ellie attacked our dog Dixie but we stopped Ellie. It happened again not long after that and she was biting onto my dogs neck and it was kinda bad but we stopped her. Now they told me that Ellie just killed a wood chuck. We are now scared to bring Dixie out there because Ellie has started this behavior. Like I said, they've had her for many years and she's never acted like this. They're now thinking about maybe giving her away. Is there a cause for this behavior? I don't think it's normal, but if it's how she's going to be for the rest of her life then they may give her away. I'm thinking there could be a reason she has started this scary behavior but I'm not sure. Any advice would be great!
There are many reasons that dogs behave aggressively, and without seeing it firsthand or having details of the situations it is difficult to diagnose. However, the first thing I recommend for dogs that display uncharacteristic aggressive behaviors is to have the dog examined by a veterinarian and discuss the recent changes in behavior with the veterinarian. Hormone changes, thyroid problems, joint pain, and many other treatable physical issues can cause aggression.
Aggression is a behavior that people view differently from animals. For people, it is socially unacceptable to bite, push, or invade other people's space. However, it is important to remember that each species of animal has their own socially acceptable behaviors. For dogs, biting is an acceptable behavior in some situations. There are also different levels of fighting, and dogs are fairly specific about how far they take the fight. Fights that look bad are often meant to establish boundaries between the two dogs. Serious fights occur when the attacking dog draws blood, which indicates an actual attempt to harm the other dog. Usually when dogs become aggressive there are signs that the dog was displaying that go unnoticed prior to the incident.
It is also important to examine each incident on it's own, without lumping it into the same category as the other incidents. For example, when Ellie killed the woodchuck, it was most likely for a completely different reason than her aggressive incidents with your dog. For dogs in general, this is a completely natural behavior. Ellie may have simply killed the woodchuck because her prey drive kicked in and the woodchuck wasn't fast enough to get away. However, underlying veterinary issues like I described before can also cause these behavioral changes, so it is important to rule them out first.
Regarding the issues between Ellie and Dixie, you mention that they have gotten in a "few playful fights" before. Then Ellie attacked Dixie, and later attacked again more aggressively. I don't know either dog or the specifics of the situation. However, it appears this is a pattern of behavior that has progressed over time, and there could be underlying social issues between Ellie and Dixie. If there was no blood during the attacks, it is likely that Ellie is either just uncomfortable with something Dixie is doing or that one or both dogs is getting too excitable during playtime, causing tension and some aggression.
First make sure Ellie gets the vet exam. If there was any blood during the fight and if the vet doesn't find anything wrong with Ellie, it would be a good idea to have a qualified trainer assess the situation. If you decide to let Dixie and Ellie play again, I would strongly suggest starting with long walks together first with each dog on a leash. The day of the first walk, don't let them play together. Each meeting afterwards, start again with a good walk and if you are comfortable you can allow them to play while supervised, starting with a couple minutes and increasing their play time each time as long as they are getting along well. Above all, encourage your aunt and uncle not to give up on Ellie. They know Ellie best and are probably the best people equipped to deal with her behavior. If the aggression continues to increase and they feel that they must re-home her, encourage them to contact a local rescue that will take dogs with a history of aggression toward other dogs. However, with a vet exam, structure, and patience I suspect that Ellie will be back to normal. Best wishes and good luck!