
This is interesting, I have different breeds and sexes and some seem to have better metabolisms than others.
My male pug is 8kg and my female pug 6kg, both neutered. The male gets roughly a third more food than the girl and is in perfect lean muscled proportion, during the day he never moves from the couch but does have the occasional burst of energy. My girl is slightly pudgy round the shoulders but I can't reduce her rations any more as she will start to sick up bile, she is very active as she never leaves my side for a second.
My two male Chows, one neutered, one not, weigh around 32kg; my female neutered Doberman weighs 34kg. The Doberman gets almost twice as much food as the Chows and I struggle to keep the weight on her. She is however on Soloxin. I have noticed that none of my Chows have ever needed much food compared to other breeds, they're not particularly lazy but just don't burn calories easily. Maybe they save energy not trying to keep warm due to their thick coats?