I don’t know that .25 percent fat is much difference (.0025 g/100g of feed more!). My layers do fine on a 21 percent protein layer feed (it’s calories that matter for cold, not protein (growth and egg production)). I’ve seen chicken people offer suet or lard to their hens in extreme cold and am thinking about doing the same for my birds when the temp drops sub zero (F). What kind of Canadian winter, Winnipeg or coastal? I grew up in Minnesota and spent a number of years on the northern border (now that is cold!), still gets a bit chilly here but almost tropical by comparison! Was rather surprised when we visited the Alaskan coast to discover the climate is also mild by comparison but I guess the ocean moderates the temp a bit (totally a land lubber here!). This will be my first winter with quail, curious to see how they do! But if Holsteins don’t frostbite their udders during a month of -30F, maybe the birds will be okay too.