Hi there, i have a 1 year old bullmastiff which i feed him twice a day on cooked pet mince and complete dog food, he gets 1lb of the mince and 1 mug full of betta complete food but he looks for more when he is finished. He also gets dog treats a few times a day. I dont want him to put on to much weight as he is still a baby but what can i do to make sure he is getting what he needs? i aslo give him chicken wings and egg's as a treat as well, any help please?

Firstly I would stop cooking the mince...feed it raw.
Other than that if he looks well on what you are feeding him then don't worry ....
If you are concerned about him still being hungry but don't want to increase his food then try adding vegetables into him meals...will bulk the meal up without putting weight on your dog.I put all my veges through a food processor so they are VERY finely chopped ...alternative is to use the pulp from a juicer
Archer