Farmer's have been doing this since electricity came to the farm . My Grandfather farmed about 300 Acres and had approximately 8,000 Chickens . The lights in the Chicken House were only turned off about 2 hours a day . To the laying chickens it was another day after 2 hours of darkness .
aren't they going to notice it's winter in Moscow?
Not likely.
In the dead of winter cows are put inside a heated barn so they don't freeze to death. As far as they know outside the barn they could be in the pastures of Cuba.