|Elementary Resources | Links | Submit | About|
Hatching Eggs: A Step by Step Guide
Submitted by Pam from Tulsa
Fertility and Candling
Fertility is rarely 100%. When the flock is of good producing age and the right proportion of males to hens are penned together, it can be assumed that a fair amount of eggs will be fertile. Fertility may vary from 55% to 95% with season, condition and type of birds. A good average expectancy may be that 50% to 75% of the eggs will hatch.
Fertility of eggs cannot be determined before incubating them. After 2 to 3 days, white shelled eggs may be candled to see if embryos have developed. Cracked or damaged eggs do not hatch and often develop odors and should be removed when detected.
Uniformly colored or white shelled eggs may be candled by placing a light bulb under a box or can. A hole must be slightly smaller in diameter than the egg through which light will pass. Place the egg over the hole, if a cloudy spot or mass is observed, this can be assumed to be a growing embryo. If the contents of the egg allows light to pass uniformly through it, it can be assumed that the egg is infertile.
The Air Bubble in the Egg
Soon after an egg is laid, a small air bubble forms in the large end under the shell. A membrane separating the mass of the egg and the air bubble serves as a diaphragm to relieve stress and pressure resulting from thermal changes of temperature. The drier the ambient air is, naturally the more fluid is depleted and the faster the bubbles grows. Correct humidity in the incubator insures that the bubble does not grow to a certain degree by the time the embryo is ready to hatch, but that the air bubble does not enlarge to the point of depleting the fluids that are necessary for the final growth of the embryo.
The importance of correct humidity is more apparent at the end of incubation. The normal condition is that the bubble has enlarged to the point where the chick can reach his beak through the membrane wall and pick around the shell breaking the bubble area off as a door. If humidity has been excessive, the chick may not reach the bubble but will pip the shell in the fluids under the bubble and may drown at that moment, before he is able to go any further with his effort to release himself from the confines of the egg. On the other hand, if humidity has been too low, the bubble will be oversized and the fluids under it will have dehydrated to the point where final development of the embryo will be retarded and the chick may become stuck to the shell when it pips. In this condition, the chick will exhaust itself but will not be able to get out of the shell. After half a day, a chick that is stuck to the shell, after pipping, may be relieved by pulling the top of the shell off.
Positioning of Eggs
An incubating egg should set in a normal position as it would on a flat surface; that is with the large end slightly higher than the point. An egg that persistently has the small end elevated may cause the embryo to be misoriented with the head toward the small end. In the misoriented position, the chick is likely to drown on pipping. Therefore, it is quite important that in general, the large end of eggs should be slightly higher than the small ends; or as they would lie naturally on a flat surface.
Eggs that aren't turned regularly do not hatch! Turning 3 times a day seems to be adequate for the chicken. Turning is essential in the early stages. The last 3 days of incubation when the bird is preparing to hatch it is not recommended. If not turned to a fresh position frequently during the early stages, the developing embryo touches the shell membrane and sticks to it causing abnormal growth. Turning the egg aids these movements within the egg. The turning can determine if the chick will emerge successfully at hatching time.
A fresh egg takes up the temperature of its surrounding, but as development proceeds the embryo generates its own body heat. By hatching time, it has an internal temperature. Chicken eggs should incubate at 99.5 degrees, quail and duck at 99 degrees.
What to do With Hatched Chickens
Do not be in a hurry to take chicks out of the incubator. Gallinaceous birds, such as chickens, quail, and pheasants survive up to 3 days without feed or water. The yolk of the egg is drawn through the navel into the stomach of the baby bird before it hatches. This, then provided nourishment for the transitional period from the time the bird hatches, fluffs out, gains strength and becomes active enough to go out and seek food. Chicks continue to grow and develop in the incubator, before they receive food. Of course, they do not gain weight, but they do gain in stature, activity and use of their faculties.
They will instinctively be interested in drops of water, each other's toes, and other objects of possible experimentation. Do not assume from these evidences of interest that the chicks are hungry. It is simply nature's way of experimentation, exploration, and learning of the young. In general chicks are taken from the incubator after 24 hours. No harm is done if they are not taken out for 48 hours after they hatch.
Feed and water must be before the birds at all times from the time they are out of the incubator. Do not dole out a measured daily ration. Rather, have sufficient feed and clean water to last from one feeding time to the next. Do not let feed or water run out!
Baby birds should be fed a dry mash. Chicken and pheasant chicks do well on baby chick mash. Solid grains are not suitable for feeding baby birds. No grit is needed when a mash feed is used. Best source is a poultry feed store.
Water receptacles are a problem with baby birds during their first week, in that if they can, the birds will drown themselves. The urge to get into water is thought to be related to the fact that the birds are fresh out of the fluids of their natural environment. The younger the bird is, the stronger the urge to throw himself completely into any water that is available. After a few days, certainly a week, this instinctive compulsion to flounder in water disappears.
A common device to prevent drowning is to use a shallow water cup with marbles set in the water over the entire drinking area. The chicks will drink in the spaces between the marbles.