Short answer: the biggest reason a layer flock lays fewer eggs in winter is shorter daylight, not cold. Hens need close to 16 hours of light a day to keep the hormones that drive egg-laying switched on, and natural day length in December and January falls well below that. Add light on a timer, expect hens to eat more to stay warm, and never let the water freeze or run dry — those three fixes cover almost every winter drop that is not caused by disease or age.
Egg numbers move with the seasons even when nothing else changes. Farmers often blame the feed first, or assume the hens are getting old, but in a healthy flock on a proper ration the pattern almost always traces back to light, cold-driven feed intake, or water — usually in that order.
What should you check and target this winter?
Four things move the needle before any medicine or supplement does. Work through them in this order.
| What to check | Winter target | Why it matters |
|---|---|---|
| Total daily light (natural + artificial) | About 16 hours, not much past 17 | Below this, hormone-driven egg laying slows; too far past it can work against production (FAO) |
| Light intensity at bird/feeder height | Roughly 10–30 lux | The level reported for sustaining peak production (US Poultry Industry Manual, via The Poultry Site) |
| Feed access | Full feeders, checked more often in a cold snap | Cold-stressed hens eat noticeably more just to keep warm (Poultry Science trial) |
| Drinking water | Checked at least twice a day, never frozen or empty | Hens suffer after about 10 hours without water (Kansas State University Extension) |
Why does light matter more than anything else?
Light reaching a hen’s eye signals the pituitary gland to release the hormones that start ovulation and shell formation. The Food and Agriculture Organization explains that as the light share of the day falls — which happens naturally from mid-summer to mid-winter — sexual maturity slows in young birds and egg production is reduced in hens that are already laying. The same FAO guidance stresses that this needs a steady, reliable light supply: breaks in an artificial lighting programme can make the drop worse, not better, which matters on any farm that loses power through the evening or early morning.
The practical target reported across commercial layer guidance is about 16 hours of total light a day, at roughly 10 to 30 lux measured at bird height, according to the US Poultry Industry Manual. The FAO adds an upper limit too: pushing the effective daylight proportion past about 17 hours a day can work against egg production rather than help it, so more light is not always better.
How do you build a simple lighting schedule in an open shed?
- Add the extra light at one end of the day, not randomly. Most commercial guidance extends the morning side, so hens are never caught by sudden darkness while still active on the floor or in the nest boxes.
- Put it on a timer. A timer holds the same total light length every day, which matters because the FAO warns that broken or irregular lighting can undo the benefit — plan for load-shedding with a small inverter or battery light on the circuit, since a power gap works against the flock the same way.
- Keep bulbs clean and evenly spaced. A dusty bulb cuts the light that actually reaches the birds; aim for light bright enough that hens can clearly see the feed, closer to the 10–30 lux range above than to near-darkness.
- Stop at about 16 hours. There is no advantage in pushing much further, and the FAO notes it can start working against you.
Is cold weather itself the problem, or is it mostly about light?
Mostly light, but cold is not free. A controlled trial published in Poultry Science kept laying hens at about 12°C and compared them with hens at a comfortable 24°C. The colder hens ate roughly 19% more feed — 133.7 g a day against 112.7 g a day — yet egg production and egg weight did not differ between the two groups. What did change was feed conversion, which got significantly worse in the cold group: the extra feed was going toward keeping the birds warm and adding body fat, not toward more eggs.
A cold shed with good light and enough feed can still lay close to normal. A flock that is cold AND short of light, or cold AND short of feed, loses on two fronts at once — the combination that actually drains egg numbers on many open-sided Punjab sheds in December and January.
How much extra feed will your flock eat in winter?
Expect intake to rise once temperatures drop, even without any change to the ration itself, by roughly the 19% margin seen above. Kansas State University Extension confirms the same pattern in practical terms: birds will consume more feed during extremely cold and freezing temperatures, so feeders that were enough in October may run low faster in a December cold snap.
Rather than planning one fixed extra amount, check feeders more often on the coldest mornings and keep enough layer feed in store that a cold week does not leave birds short. Our layer feed range is formulated for the whole laying period, and your nearest Vital Feeds dealer can talk through a winter feeding plan for your shed.
Why is water the easiest thing to miss in winter?
An egg is mostly water, and a hen that cannot drink stops laying quickly. Kansas State University Extension warns that hens suffer after about 10 hours without water, so a drinker that freezes overnight, or a nipple line that blocks with ice, can cost you eggs within the same day — often before anyone notices the shed is short on water at all.
Check drinkers at least twice a day whenever temperatures sit near freezing, break or replace ice promptly, and keep lines and bowls clean the way our feed quality checks page recommends for feed — a flock drinking well and eating a clean ration gives winter light its best chance to work.
What does this mean for layer farms in Pakistan?
Open-sided sheds common across Punjab give hens plenty of natural light in summer but lose hours fast once the days shorten, and many of the same farms face evening load-shedding right when extra light matters most. A simple timer light, a feed store that assumes higher winter intake, and water checked twice a day cost far less than the eggs a flock loses to all three problems at once. Our summer heat stress guide covers the opposite season, and the layer feeding schedule has the full week-by-week ration for pullets coming into lay.
Written by the Vital Feeds editorial team.
How this guide was made: the light and hormone information is from FAO small-scale poultry production guidance, the light-hours and intensity figures are from the US Poultry Industry Manual via The Poultry Site, the cold-stress feed intake data is from a peer-reviewed Poultry Science trial, and the water guidance is from Kansas State University Extension, all read in full; the draft was AI-assisted and fact-checked against those sources on 16 October 2026.
Seeing fewer eggs than usual this winter? Message the mill on WhatsApp (UAN 0311 1555136) with your shed's light hours and egg count, or find your nearest Vital Feeds dealer for a winter layer feed recommendation.