The science behind backyard chickens

Published 12:00 am Saturday, December 19, 2020

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It’s December now, and county agents everywhere are writing their annual “protect plants from freezing” articles. Dan Gill wrote a good one recently (easy to look up if you’re interested), so I’ll give that theme a rest. You’ve already read my last couple of holiday articles (right?) about Christmas tree selection and poinsettia care. So I’ll surprise y’all this month with something not horticulture but poultry science – backyard chickens.

Lots of people bought them this past spring, and lots for the first time. They’re easy to care for, amusing to watch, and you’ve been enjoying fresh eggs until recently… then they quit laying. If you’re new to raising poultry this may be a disappointing surprise. But don’t worry; it’s part of their annual cycle. Chickens need at least 12 hours of sunlight daily to lay eggs, and 14-16 is better. They each have a “pineal gland” whose function is to measure daylength and tell the bird’s brain when to lay and when to lay off.

When fall comes and days get shorter, egg production drops off. This is a holdover from when “wild” chickens laid eggs to hatch mostly in spring. Feathers drop off as well, and the overall process is called “molting.” While in most years you’ll just notice some feathers on the ground and maybe some thin-feathered chickens, 2020 is not most years. The feather drop seems to be severe this year according several people I’ve heard from, as well as my own flock.

After two or three months the hens’ feathers will fill back in. You may get an egg or two now but they’ll start back again in earnest when days get longer in spring. You can actually forgo the molting process by supplying additional light when days get short, as is done in commercial settings. Simply put a light on in the coop that’s bright enough to read a newspaper by at bird level. Make sure all areas of the coop are well-lit, especially the feeder and waterer. Supply enough light for a total of 14 hours daily and you should be fine.

If they have been allowed to molt but feathers haven’t grown back in several months, you may have a problem. The most common is the presence of a rooster in a flock. They can be amusing but are not needed for egg production. It’s recommended to have no fewer than eight or 10 hens per rooster. Otherwise his *ahem* “affections” may be too much for the gals and their back feathers in particular will be rubbed off.

Parasites are another possibility, though less common on healthy birds. You can apply diatomaceous earth (organic) or permethrin (conventional) to chickens on a regular basis to keep mites, lice, ticks and mosquitos off them. Check the label for frequency.

A diet short in methionine (an essential amino acid especially needed for feather production) can also prevent feather growth. Hens lacking methionine may even pluck out their own feathers in an effort to ingest more. Commercially available chicken feed will have the right balance of all dietary needs. Everyone with backyard chickens gives them “treats” sometimes in the form of table scraps, garden waste, birdseed, etc. If you overdo it by a lot, especially with corn, this may also cause a methionine deficiency.


If you want to know more about gardening, landscaping, or anything else horticultural, (or poultry-related) contact the St. John & St. James Parishes County Agent André Brock at Also, the LSU Ag Center’s website can be accessed at with lots of user-friendly information, including this article.