I do the same thing with my pheasants and quail. They get extra grains (milo, corn, barley, sunflower hearts, red winter wheat) when winter is like the one were having, occur. Went from snow to 68°F in 2 days the 1st go around.When I feel bad for my birds I make sure that they have plenty of carbs in the form of cracked corn and scratch. I don't worry as much about the protein during those times as we get shocking temperature shifts here where I live from 70F nights to 30F nights. Then back to 60-75F nights 2 days later in winter.
If you antrhopromorphize(spelling) as we do then give them their candy and feel better as they make their own heat and have their own down jackets.
Right now, it's 27°F we have had freezing rain, sleet and snow flurries, today! Tonight it's suppose to get down around 20°F by Saturday they are saying it will be back in the 70's, Ugh, tired of this winter. Anyway, they all got double the normal, today.