If you want to learn more about training and controlling your Jack Russell, my ebook is bound to save you hours of training trial and error and relieve a lot of stress from the process: The Jack Russell Lover's Ultimate Guide to Training comes complete with a full chapter on mix breeds.
Extreme dog aggression
My 8 yr old guy is the sweetest little thing. Very good with us, our cat, the grandchildren, company. Take him on a walk and its a nightmare. When he sees another dog he goes balistic. It is embarrassing. He barks, holds his body in an aggressive manner - tail up, ears up, eye contact to the other dog, lunging at the other dog...I've tried different collars, turning around and walking the other way, yelling, scolding. Nothing is working. I hate taking him out on walks anymore. Maybe I should hire a dog trainer.
Also, when we leave for work he is peeing in the house. And this is after we walk him to eliminate. We bought a crate for him, and have staggered our work schedules so he isn't home alone too long, but sometimes he pees in his crate. Any suggestions for this?