While waiting for feed testing results; how much light do hens need to lay eggs

[saysfaa]

I see many places that say hens need 12 to 14 hours of light to lay eggs.

Obviously, that isn't the whole of it because otherwise hens would not lay eggs between September 20th-ish and March 20th-ish, unless one lived very near the equator.

Last time I researched this, I found that hens need 12+ hours of light for full production of eggs. I think I remember 14 to 15 or 16 hours for maximum production but either way, what explains the extra weeks before/after the equinoxes?

It seems, they need about 9 hours for any of them to produce any eggs.

I doubt that is all there is to it. Among other things, some are more sensitive to light levels than others.

Also, how much light is needed to count as those hours?
Is it only the intensity or does wavelength matter?
Do clouds change the intensity and/or wavelength of sunlight?

Edited from simply saying "sorry" as the entire message for hitting the wrong key.

 

[SourRoses]

You should have spankings with a keyboard!

 

[saysfaa]

 

[JacinLarkwell]

Well, when the week from hell (roughly the 10 days before christmas) came, I had birds exposed to 2 red bulbs for 24 hours a day and still got no eggs from them until about 2 weeks ago at most I think. They laid maybe 2 or 3 days earlier than the ones outside with no light

 

[saysfaa]

Anyway, I'm not dismissing any other proposed explanations of why so many flocks have had unusual laying patterns lately. But instead of simply going back and forth with "I think" and "but I think".... until some new information comes - such as test results...

Around here, we can expect very heavy, low cloud cover from October through December. Then January is usually much colder. And clear.

This year, the very heavy, low cloud cover stayed. With, literally, two 15 min breaks. One last week and one the week before. I pay close attention to it due to Seasonal Attitude Disorder.

It became too dark to read a newspaper noticably earlier.

Turns out, clouds change the wavelength that reaches the earth, also...
Link

And wavelenght affects how often a hen lays an egg, even if the hours of exposure to the light are the same... link

These are not thorough study of this... it is just enough to be interesting. And, perhaps, a small piece of the puzzle.

 

[saysfaa]

Well, when the week from hell (roughly the 10 days before christmas) came, I had birds exposed to 2 red bulbs for 24 hours a day and still got no eggs from them until about 2 weeks ago at most I think. They laid maybe 2 or 3 days earlier than the ones outside with no light

Hm, the link says red light resulted in the most eggs.

Eh, it was an idea.

Do you have feed from then? That Aunt Angus could test

 

[JacinLarkwell]

Hm, the link says red light resulted in the most eggs.

Eh, it was an idea.

Do you have feed from then?

No. It's not the ones people are getting up in arms about anyways. The week from hell was aptly named (-20 days, and several losses to the different flocks) and all the birds exposed to the light apart from a trio of hens were moved under the lights because they were in danger of succumbing to the cold.

 

[saysfaa]

That is interesting, too.

Stress on top of just barely enough light (for some of the other flocks; if yours had electric light, maybe not yours). Because stress can also change nutrient needs. Feed that is made to meet the average needs, just barely, may not meet the needs under a lot of stress. Even though it is what it says it is.

 

[JacinLarkwell]

I'm just thinking it was the stress and weather. I wouldn't be laying either if I was a chicken until a week or two ago. We had another temperature plummet this weekend and I'm fully expecting eggs to slow again. Not that I'll complain, I already have way too many and only a fraction are laying anyways

 

[centrarchid]

I see the following impacting egg production when controlling for genetics: photoperiod, age of hen, feed quality and amount, and finally cold stress. Later is really impactful when photoperiod is marginal.