Do Hens Need a Rooster to Lay Eggs?

Do hens need a rooster to lay eggs? No. Hens will lay eggs with or without a rooster.

Do hens need a rooster for the eggs to hatch? Yes and no.

Wait, what?

That’s right. Sometimes chicken eggs hatch even without a rooster.

What is parthenogenesis

The long, fancy word “parthenogenesis” refers to the process by which an unfertilized egg develops an embryo. It is a common means of reproduction in reptiles, but is not so common in birds.

Yet it does happen in chickens, more so in some breeds than in others. The anomaly has been studied in dark Cornish, white Leghorns, barred Plymouth Rocks, and Rhode Island Reds.

And the condition is heritable, meaning it is passed along to future generations. Assuming the parthenogenic egg hatches.

Most parthenogenic embryos die early in incubation. Any eggs that do manage to hatch will most likely come from a dark Cornish hen. And they will most likely be cockerels (male chickens).

How are chicken eggs fertilized

Although a hen will lay eggs even without a rooster, typically the eggs must be fertilized by a rooster in order to hatch. When a rooster and hen mate, the rooster’s sperm is temporarily stored in the hen’s sperm storage tubules.

A hen normally ovulates, or starts a new egg, about five hours after she lays the previous egg. As she lays the previous egg, some sperm releases from the storage tubules. The released sperm, then, have about five hours to wriggle like tiny tadpoles through the oviduct to fertilize the next developing egg yolk.

An egg produced on the day of mating will not be fertile. One laid the next day may or may not be fertile. An egg laid on the third day after mating should be fertile.

How long the hen’s eggs will be fertile depends on how much sperm fills the storage tubules, which can cache semen from multiple matings and multiple roosters. Hens of single-comb breeds tend to produce fertile eggs longer than rose-comb breeds.

The average duration of fertility from a single mating is 10 to 14 days. To assure fertile eggs come from the mating of a specific hen and rooster, isolate the two together and wait at least three weeks before saving eggs for hatching.

What is treading

While mating, a rooster stands on a hen’s back, balancing himself by bracing his claws against her shoulders. To get a good grip he makes a few quick movements of his feet, called treading. A well-mated hen will eventually lose feathers along her shoulders and back.

A mating saddle will protect a hen’s back from treading damage. Apply saddles at the onset of mating season in spring, or at least as soon as your hens start missing feathers because of treading.

Mating saddles are not year-around fashion accessories. They should be removed in the fall, after hens molt and have fresh new plumage. At that point, wash your mating saddles and store them away until next spring’s mating season.

Do roosters have penises

Are you surprised that eggs sometimes hatch without a rooster? Here’s another surprise: roosters have no penis.

Yup. That’s right!

Like the males of 97 percent of all bird species, a rooster has no penis. So how does he “do it”?

Instead of a penis, a rooster has two tiny nipples, or papillae, that serve as mating organs. They are located in the rooster’s cloaca, the chamber just inside a chicken’s vent.

While the rooster is balancing on the hen’s back, the hen lifts up her tail and the rooster bends his tail downward. In what’s known as a cloacal kiss, their vents press together and the rooster injects sperm into the hen’s cloaca.

Here are two more odd factoids: A rooster can control how much semen he releases, maybe saving some for another hen. And a hen that doesn’t like a particular rooster can squirt his semen right back out.

Hen-to-rooster ratio

The optimal number of hens per rooster ensures that the rooster can get around to all the hens for good egg fertility. Too many roosters, though, may mate hens so often as to cause serious injuries from treading. Or the roosters may spend more time fighting than making love.

The optimal mating ratio varies from breed to breed and depends on flock size, bird size, and the breed’s activity level. As a general rule, a good hen-to-rooster ratio for active lightweight breeds is 12 to 1. For heavy, less active breeds, it’s 8 to 1.

A lot depends, too, on the rooster’s age. Immature males and aging roosters, for example, can typically handle only about half as many hens as a fully mature, virile male.

Lots of flocks have extra roosters that get along just fine, especially if they were raised together as chicks. A way to minimize fighting is to avoid having two roosters that may consider each other rivals. For some reason, three roosters seem to have a more calming effect on each other. Multiple males are also more likely to get along when they have plenty of living space where each can gather his own harem of hens.

Of course, if you don’t want or can’t have roosters, you really don’t need one. Your laying hens will get along just fine without a rooster. But…

Hen and rooster interaction

Without a rooster you’ll miss out on half the fun of having chickens. A rooster is full of personality, more so than a hen.

Hens typically gather around a rooster while out foraging. The rooster remains wary, watching out for any potential dangers to his hens.

An aggressive rooster is generally not mean. He probably just perceives some danger to his hens. And he has a pretty good memory. So if, for instance, your floppy muck boots scare the hens, he’ll remember next time he sees those menacing boots.

A rooster can be a peacemaker. If two hens engage in a peck-order squabble, the rooster is likely to rush over and break up the fight.

A rooster that finds some intriguing treat will food-call his hens to come partake. When you share a treat with your flock, the rooster takes credit by bringing the hens’ attention to the treat.

Roosters crow a lot. They start at dawn and may crow periodically throughout the day. Some people find that annoying. Most chicken keepers like the sound. And given all the roles a rooster plays, he certainly has a lot to crow about.

Gail Damerow has written many books about chickens. Those available at Tractor Supply include Storey’s Guide to Raising Chickens, Hatching and Brooding Your Own Chicks, The Chicken Health Handbook, and more. Visit Gail’s blog at gaildamerow.com.

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