My Huskey/ chow / wolf ; 130 lbs; 10years old attacts my other dog?

I also have a 35lb mixed female - she's 11 ; the big dog has been with for 6years and every 6 months aprox. The big dog attacks the little one; viciously and draws blood ; its only when I'm home and I have to pry the big dog off my little Willowmeana.; then there fine again. Should I consider putting Sage ( the big dog ) to sleep seeing the aggression is continuing still? Sage has also become incontinient but shows no other health problems.

The dog is 10 years old, why would you want to put it down if it has NO other health problems? Have you considered a refresher coarse of obedience classes? Or just seperating the two dogs?