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Jack Russell’s are prone to brain tumours. If your dog has never attacked your partner and your partner has never mistreated your dog (or your child) then it’s time to put your dog down.
I had a Jack Russell growing up. He was territorial and fiercely protective- but he never really once attacked anyone in the family. He once bit the next door neighbours child because this kid jumped the fence and thought it was hilarious to taunt the dog and run away. The dog bit him and everyone agreed (including the parents of the kid) that the kid deserved it.
That Jack Russell lived to be about 9 years old. Before the end he turned mad. He would attack wheels on cars and bikes if they were turning. He barked constantly.
As an adult I bought a chihuahua that very clearly had Jack Russell in him. He was a bad dog and had been since he was a puppy. He attacked me twice. He bit my ear which lacerated the cartilage and took months to heal. He bit my face and I now have a small scar on my face - 13 years later.
When he bit my ear he was on the end of my ex boyfriend’s bed as I was saying goodbye as I left for work. He attacked without warning and wouldn’t let go of my ear.
The second time he bit my face after suddenly attacking his brother (I had two dogs who were brothers from different litters). There was no warning. He attacked his brother and then attacked me as I was sitting on the couch.
I gave up the dogs as I was moving and couldn’t take them with me. I later heard he attacked my ex boyfriend’s friend quite badly. That dog should have been put down. He was well cared, loved and was exercised. He still attacked me.
I hate Jack Russells now and I never ever want to own another Jack Russell again. They are one of the worst dog breeds to own.
I would never have a Jack Russell if it had a young baby.
If your partner has never mistreated your child or your dog - it’s time to put the dog down.