I was wondering if they made any kind of muzzle that my dog could wear during the day that would allow him to still eat and drink.

I have a 5-year old male German Shepherd that is very aggressive towards the others shepherds when my female is in heat. She is almost 10 and cannot be spayed due to congestive heart failure. I keep her in another part of the yard during heat but even during this time, my male shepherd will try to about kill my other males/females. I have 5 dogs total and do not breed them anymore. I am having him neutered next week but I was wondering if they made any kind of muzzle that he could wear during the day that would allow him to still eat and drink. Actually eating is done in the evening while I'm home so I guess I mainly need one where he could still drink water. We have a large yard with a 5 foot chain link fence with a hot wire at the bottom. I've actually thought about finding him another home but I know that wouldn't work and he's very loyal, protective and a great pet other than these times. Any suggestions would help.

Janet