Are you really serious? I haven’t read anything about it making them crazy or effecting their eyes. I’m not sure you realize how big of a shed they are in or maybe where the lamps are. I have the lamps hanging from a 6 foot plant hanger so unless they are on the roost it does not help much at all. Once I blocked most of the ground level drafts it did get better. Still you can see your breath & it has been raining almost every day now for 2 weeks so our grounds are saturated. I only use the heat lamps when it goes below 30F. This morning with the wind chill it was 9F. Something extremely rare in Mobile Alabama Lol.. I guess I would rather have crazy chickens than dead ones! (Maybe) I am a first time Mother Hen myself so I guess I was over cautious!
I'm really serious. I've always known any earthbound animal needs a daily dark period. Sleep deprivation, white room and constant light are common torture methods around the world.
I just finished reading a text book called 'Poultry Lighting,
the theory and practice', by Peter Lewis and Trevor Morris - out of the UK and Africa with various PhDs in poultry husbandry. It is a pretty heavy read. ISBN# 0-9552104-0-2
Continuous illumination causes behavioral problems and fertility problems.
Enlargement of the eye in birds exposed to continuous light is thought to be caused by an accumulation of fluid. Buphthalmia and corneal flattening, corneal thickening, cataracts, lenticular thinning and damage to the retina and several other eye issues. Broilers, layers and turkeys exposed to continuous light develop elongated eyelids, have increased sclera exposure, cornea curvature and become blind.
That's the issue with first time' Mother Hens'. They don't know how hardy most breeds of chickens are. I only try to use heat when it gets below 0 F if I can utilize a safe means of elevating the temp a bit. And I only do that because I have lots of Mediterranean roosters with huge combs and wattles. If I only had hens, I wouldn't worry about it. I've never had frostbite on any breed of hen down to -19F. But I give enhanced ventilation year round.
Wind chill has no impact indoors. Cold may be rare in coastal Alabama but it isn't rare in the chicken world. 25 eight week old chickens should be able to keep themselves warm well below zero without heat. That is unless you have some foo foo chickens like seramas or silkies.
To add heat, you don't need to subject them to continuous light.
They make ceramic heat emitters from 25 to 300 watts.
You might be cold but your chicken aren't. They go to sleep at night wearing a down winter coat, not pajamas.