Hatching Eggs in an Incubator
The most productive modern chicken breeds (in terms of meat and eggs) are carefully selected genetic strains that won't go broody. So if you want more of them, you have to buy them again from the commercial hatchery—or incubate their eggs yourself. Home incubation is actually a practical option, especially with the inexpensive, but functional, small incubators available for sale. Even the smallest size, which will hold about a dozen eggs, can keep them adequately warm, humidified, and turning. Nevertheless, you're bound to have some eggs that don't hatch. Fifty percent is a poor hatch rate, 70 percent about average, and 85-90 percent is very good. If you have an incubator and can buy fertile eggs locally for reasonable prices, it's probably cheaper than mail-ordering. Of Eggs and Heredity: Look carefully to see whether one end of the egg is pointy or round. Pointy-ended eggs make roasters, says Ellinor Nürnberg of Ontario, Canada. Round-ended ones make hens. This method is 90% accurate. If you collect eggs from hybrids and crosses the offspring will not be like the parents. Raise purebred chickens of a kind you like. Then you know what you have, and you know what you're going to get. To raise crosses you'd have to do your own crossing by finding out what 2 kinds of chickens result in the cross you want, and then breed them. Whatever roosters, hens, and eggs you choose, choose the best: birds that conform to their established breed characteristics for fancy breeds, and birds that carry desirable traits of egg-laying, egg size, good health for egg-meat production breeds. If you're breeding from birds who are in their first laying season ever, wait to begin storing eggs for incubation until the hens have been laying several weeks. The first eggs tend to be smaller and less uniform in size, with lower fertility rates.
Getting Hatchable Eggs
Diet. For prime hatchability of your eggs be sure to feed your breeding birds a diet high in protein with plenty of greens and comparatively little grain. The bird, if offered excessive grain, tends to fill up on it, like a kid with junk food, when what she really needs are the protein and greens. Laying mash is not a suitable feed for birds you want to hatch chicks from, but there is a special commercial feed for them called "breeder's ration." Free-running birds will do fine, or you can offer the home-based diet (see "Protein"). Both the roosters and hens involved also need to be fed regularly and generously since a rooster's reaction to loss of body weight from short rations can be sterility, and a hen's reaction is to quit laying for a long time. In general, the more eggs a hen is laying, the more likely her eggs are to be good hatchers, because she's in such prime health. The lighter the yolk, the less hatchable your eggs will tend to be.
Rooster. If you don't have a rooster among your chickens, none of the eggs will hatch; you need that daddy chicken for fertile eggs. This is elementary birds-and-bees data, but I've met city folks who've never stopped to consider such details. Furthermore, the younger the rooster, the more likely his eggs will be fertile. (And the younger the hen, the more likely her eggs will be fertile.) A young light-breed rooster can fertilize a harem of 10-20 hens, while an old rooster can keep up with only 5-10 hens. A heavy-breed rooster, even a young one, shouldn't be assigned more than 8-12 hens. A bantam rooster is best matched with a harem of from 2-5 hens. Getting the right number of roosters for your hens takes delicate guesswork. Too many roosters causes the egg-fertility rate to go down, because then they spend more time fighting with each other than they do courting—or the egg production can go down because the hens are getting hassled too much. If there is only 1 hen per rooster, she can end up in really bad shape from too much mounting. And your hen must be compatible with your rooster, because some hens, to some roosters, will say "No."
A rooster with a frozen comb won't be sexually active until his comb heals up, which can take several weeks. A molting rooster isn't interested either. Birds in batteries basically don't reproduce naturally, because of the low ceiling. You have to raise the roof, or artificially inseminate (see "Artificial Insemination" under "Turkeys").
For a fertile egg the hen needs to have been inseminated no sooner than 24 hours before laying, and no later than 2 to 3 weeks. There is no way to look at an egg and know if that egg's mother has had a passionate embrace from a rooster in the required time frame. You'd just have to hope for the best and proceed. Once incubation has begun you can tell if the egg is fertile by candling it (see "Candling the Eggs"). But if you have actually seen the rooster mounting hens, you can start collecting eggs. A rooster has no penis. He breeds by simply pressing his vent to the hen's and extruding semen into it.
Daylight. No matter what the age of your rooster, he will be more fertile between March and May than he is during the other months of the year. More daylight causes his semen output to increase. Commercial egg-laying breeds may lay year-round; more natural breeds begin laying in February and will have fertilized eggs by March or April. That's because it takes the rooster longer to get going and become fertile than it does the hen. You can cause a rooster to get fertile earlier by extending his hours of light to 14 hours per day and warming him to 60°E Five weeks after that change, approximately, he will get in the mood. It takes the hen 2 or 3 weeks after the days get long enough to have fertile eggs. Handling and Labeling Eggs-in-Waiting. Gather them before night, if your nights are chilly, to keep them from possibly harmful low temperatures. Handle the eggs very gently and keep them either on their side or with the large end up—never with the small end up as that may cause the air cell located in the large end to rupture. Choose normal shaped, normal sized, uncracked ones. Don't wash eggs-in-waiting. The water could carry the very bacteria you're trying to avoid through the shell's pores and into the egg. If something on the egg shell is a real problem, buff it off gently. Yet very dirty eggs have been washed by desperate owners (less than 3 minutes in water 110-115°F), and the chicks lived to peep the tale. If you are incubating eggs from a variety of poultry breeds, it may help you to write on each egg—in pencil—a code designation for the breed. Write on the small end of the egg, because the large end gets broken away in the hatching process. You might write, for example, "M" for mallard and "L" for Leghorn. If you are keeping track of different genetic lines of the same breed you can give each pen a different number. In that case, you might have LI, L2, and L3, for eggs from 3 different pens of Leghorns.
Storing Eggs-in-Waiting. Placing the eggs in egg cartons works nicely, at a temperature of 45-60°F, in a place that has at least reasonable humidity. That temperature won't kill the embryo, but it will keep it from commencing development. Don't store them in an air-conditioned room. Air conditioning removes moisture, which is bad for the eggs. The temperature of your household refrigerator is probably lower than desirable and would reduce hatchability. Don't let the eggs that you plan to incubate go below 40°F, which will kill the embryo, or above 80°F, which would cause a slow growth of the embryo that weakens and eventually kills it. Actually, the embryo starts to develop at any temperature above 68°F, but the growth rate becomes a major risk above 80°F Eggs that are going to be incubated should be turned or tipped 3 times a day. The easy way to accomplish that is by raising one end of the egg carton. Then, next time, raise the other end. Start incubating eggs from 1 to 14 days after laying, better in the first week than in the second.
incubator Types: You can order incubating equipment to handle almost any number of eggs—from a dozen to 75,000. Most incubators are electric, but there are nonelectric (kerosene, oil) models available. Each incubator comes supplied with detailed directions, and they'll work best if you follow those instructions very carefully. If you have a new incubator, set it up and level it. Run it a couple days to be certain it's working as it should. Test to see if it's keeping the temperature you want. Make sure the moisture pan has water. Before using an incubator that has been used before, clean it carefully. Or you can make a homemade incubator.
Drawer from Incubator
Homemade Incubator. The proper brooding temperature for almost all varieties of eggs is 99.75°F (which is just exactly the temperature under a mama hen). The most primitive homemade incubator is something like a bucket with eggs in it. The eggs are wrapped in a cloth and a light bulb is suspended over the top. This is the least likely to work, and yet I know of people who have hatched chicks with exactly such an arrangement. What you're striving toward is a heat source that can keep about a 2- or 3-square-foot area at approximately that 99.75°F. You can make a better box-style incubator out of a Styrofoam cooler, or a cardboard or plywood box. If you make the top side of glass, you'll be able to watch the hatching. A plywood incubator with a 40-watt light bulb should be about 11 inches high, 11 inches wide, and 16 inches long, with a hinged front side for a door. With Ys-inch ventilation holes on each side—near the top of 2 sides, near the bottom of the other two—you get a natural air circulation inside your incubator. The eggs should be placed in a tray made of wire mesh fastened to a wooden frame 2 inches off the bottom. A water pan should be placed on the bottom of the incubator underneath the eggs. To test the temperature of the incubator lay a human oral thermometer among the eggs. It's all quite adjustable: the wattage of your bulb, the material and size of the box—so long as you end up with the temperature you want in the place you want it.
Commercial Incubators. If you're buying an incubator, you must first choose between a still-air incubator and a circulated-air incubator. The still-air incubators are the smallest—with capacities of about 1,100 eggs—and least expensive. Still-air incubators depend on gravity to move air through vents on the top and bottom of the incubator. The operating temperature of a still-air incubator is always set a little higher than that of a forced-draft machine— 101.5-102.75°F, depending on the variety of egg. (If you don't know the recommended temperature, go with 102°F, and you'll probably be fine.) You have to be home every day at certain times to turn the eggs. The cheapest, smallest models of all do not have a thermostat and are poorly insulated. Just as with incubating with a light bulb, this is not as cost-efficient or reliable as using more sophisticated equipment. The Hova Bator Incubators are well thought of for hatching small batches of eggs. Incubators that turn the eggs for you generally use either a mechanism that rolls the eggs or actually physically turns them. Avoid the "rollers" because eggs tend to get cracked.
Circulated or "forced" air incubators are used by large commercial hatcheries. They have fans that move air around the eggs. They cost more but give you better hatching percentages because of the improved control of the incubator environment and because the eggs are turned in a tray rather than rolled. With automatic egg-turning you are a lot freer to be away from home. Big models can hatch very large quantities of eggs. Humidaire incubators are expensive but give high-quality service. If you are planning to hatch very small eggs such as quail, ask your supplier for special advice on your incubator model. humidity: During incubation eggs lose some weight due to evaporation of the contents. The presence of humidity helps control that loss. Humidity helps your eggs to hatch. Too much humidity, however, results in a chick too large to work its way out of the shell. Too little humidity results in a chick that is glued in there.
Measuring Humidity. Measuring incubator humidity is done with a wet-bulb thermometer. "Relative humidity" is determined by comparing the difference between the dry-bulb temperature reading and the wet-bulb reading. If the recommended relative humidity is 62 percent (correct for large turkey eggs during the first 25 days), then at a dry bulb reading of 99.5°F, the wet-bulb reading will be 87.5°F. If you have a hygrometer you can measure the humidity in your incubator air. You're aiming for a wet-bulb reading of 85-87T the first 18 days of incubation (60 percent relative humidity), and 89-90°F the last 3 days (70 percent relative humidity).
Increasing Humidity. Incubator operators generally try to raise the humidity the last few days of the process. If the relative humidity wanted is 70 percent (correct for the last 3 days of turkey eggs) then the machine will be set at 99.5°F, and you'll be looking for a wet-bulb reading of about 90°F Humidity in still-air incubators usually comes from an evaporation pan in the bottom of the machine. A soaked sponge sitting in the pan can increase humidity If the weather is dry or the incubator is opened frequently you can supplement humidity by using a sprayer that emits a fine luke-warm water mist. Humidity is added by increasing the amount of evaporation area or by changing the ventilation; reducing the ventilation increases the humidity, and, in turn, increasing the ventilation decreases the humidity. Incubator Temperature: The room in which you keep an incubator should be well-ventilated and at a temperature of around 60-70°F Incubators (and brooders) are engineered to raise normal room temperature of about 70°F up to the required temperature, and they don't work properly in an unheated building and/or in cold weather. So don't let your incubator sit in the sunshine, or near a heater, near a window, or in a draft because any of those might be more than the heat control system can handle. Don't let the eggs ever get over 103°F That would probably kill them. A forced-air incubator should be set for 99.5°F; a still-air model is set for 102°F
Adjusting Temperature Setting: Each variety of bird has a specific number of days needed to hatch its eggs. If your eggs hatch in fewer than that number of days, it suggests that the incubator temperature was set a little too high. Lower that setting 0.5-l°F and incubate another batch of that variety of egg. On the other hand, if your eggs took longer than the predicted number of days, then you should raise the incubator temperature the same amount. After several trial runs of this sort, you'll know the best temperature to set your incubator at in your particular environment.
Cooling. Most incubators are modeled on the original hen, and they cool the eggs 15 minutes a day—for 5 minutes at a time—which may or may not help. Circulated-air incubators are equipped with cooling systems. So if the heat system gets turned off for a while, don't panic. Maybe it was like a mother hen leaving the eggs once a day to get food and water. Quite likely the eggs will be all right, though maybe a day later in hatching. If the electricity should go off for a long time while you're incubating, try to keep the eggs warm anyway, by enclosing the incubator in a down sleeping bag, or moving it near an alternative heat source. turning the Egg: Faithful, frequent turning is essential to the embryo's proper development. A hen on the nest instinctively does that too. Not turning the egg regularly can result in a crippled or deformed chick, the death of the embryo, or a chick that can't hatch out properly (this is because turning prevents the embryo from sticking to the surrounding membrane, which can happen if it stays in one position too long).
1. Turn the egg from a fourth to halfway around at least 3 or 5 times a day. This helps the network of fine blood vessels through which an embryo breathes to finish developing. Some incubators automatically turn the eggs once an hour.
2. The odd number of turns will ensure that the eggs will be on opposite "sides" during the long nights, rather than always resting in the same position.
3. The way to tell where you're at is to mark an "X" on the egg and turn the mark up one time and down the next.
4. Any time you write on an egg, use a pencil, not a ballpoint pen or marker pen. Ink may be absorbed through the shell pores and may harm the embryo.
5. Be extremely careful not to cause shock or jarring to the egg when you turn it, especially in its first 24 hours, when certain delicate blood vessels are just forming. Some incubator operators skip that first day completely, not even opening the incubator door once, and start the turnings with day 2.
6. After the eighteenth day of incubation, quit turning the eggs. If you are hatching the eggs of a species other than chickens, quit turning 3 days before their expected hatching date.
7. From the tenth day on, make sure that the large end of the egg is at least somewhat up. Around the twelfth to fourteenth days, the chick takes a lengthwise position in the egg. If the small end of the egg is up at this stage the chick develops with its head in that end. With its head in the small end, a chick may manage to pip (peck a hole in) the shell, but it's practically impossible for it to hatch clear out. In a broody hen's nest, under natural circumstances, an egg lying flat will just naturally have the larger end a little more elevated. In the incubator you consciously have to make sure it's like that.
ventilation: Whether you're using a homemade incubator or a commercial one, you need ventilation for it, because the developing baby chicks are taking in oxygen and breathing out carbon dioxide right through tiny holes in the shell. Without an adequate air supply, the embryo will suffocate.
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