CHAPTER IV.INCUBATION
In order to get a better idea of artificial incubation, let us first examine a few facts concerning the way in which the hen hatches hereggs in the natural process. The fertile egg is hatched when the egg is subjected to a heat over 100 degrees, F., for a period of about twenty-one days. The mother hen, by setting on the eggs for this period, will bring off her hatch on the twenty-first day, if she has been given ordinary care. Let us see what are the principles involved in this natural incubation, that we may the better understand the artificial method of incubation.
When the hen first becomes broody, and wants to sit, she might try to “steal her nest.” This is another way of saying that she will try to locate some secluded spot, and after she has succeeded in laying a dozen or fifteen eggs, she will then spend nearly her entire time on the nest, until she proudly marches back to her old haunts with a small clutch of chickens.
It is a natural instinct of most hens to become broody in the spring of the year, to reproduce their kind. A constant desire to sit on the nest is a sure sign of broodiness. When one has the eggs to put under the hen to hatch, it is best first to try to secure a general purpose bird for this method, as they have been found the best, for reasons previously stated.
Now let us prepare a nest for the bird, so that she will have a good opportunity to do her best work. We can either partition off a part of the chicken house, or we can fix up a nest in another building entirely, such as a garage, barn, or any other building that we may have on the premises. Next let us take some soil, and make a round nest, over a foot in diameter, and four or five inches deep. Then we will dig out the center of the nest, so as to make it hollow in the middle, leaving at least two inches depth in the center. Then we will cover this earth with a few inches of cut straw, shavings, or leaves, and press this covering down to conform to the shape of the soil foundation. We can now place our eggs for hatching in the nest, and put the bird on them. However, best results will be obtained if we wait until towards evening before we place the bird on the nest, as she will be more contented then. Take the bird that you have chosen and place her gently upon the nest of eggs. If she is at all broody, she will be quite contented when she feels the eggs underneath her, and settle down to business at once. The hen should spend practically all of the next threeweeks upon the nest, the only time that she should be allowed to leave being the short time that she takes food and water twice a day. Having a quiet place, and giving her nourishment twice a day, she will be quite contented. The hen does not need any special ration during this time, other than one that is fairly heating. Corn is excellent during this period, supplemented with a few other grains, such as oats, wheat, etc. A sufficient amount of fresh water should be available, together with some kind of green food, if possible, such as cabbage or mangoes. The hatch will not be endangered by the hen leaving the nest to eat. In fact, it is beneficial to the eggs to be temporarily cooled, at least once a day, while the hen is off the nest for a while.
The hen has a habit of turning the eggs under her every day, not only removing their position from the center to the outside, and vice versa, but also turning them over, so that perhaps the part of the egg that was in contact with the nest one day, will be in contact with the hen’s body the next day. Or, in other words, she turns it half way around. These are all peculiarities that we have to imitate inartificial incubation, if we would be successful. Now that we have seen the process of the natural method of incubation, let us see how the ingenuity of man has successfully imitated the mother hen, and made possible the hatching of a far greater number of chicks than the hen can naturally hatch.
In the first place, there are a great many incubators on the market, some being made to sell, and others being made to use. How shall we determine the make to buy? That is not the easiest question in the world, if one has had no previous experience with incubators. Do not necessarily buy the incubator that is advertised the most. Sometimes incubator companies have to advertise extensively to do a sufficient volume of business. The safest way to choose an incubator, if you really intend to purchase one, is to get the advice of some one who is using one, and has had success with the machine that he has used. Some of the cheaper makes have the trouble of too varying a temperature, especially during the night. If one has to arise five or six times a night for three weeks to regulate the lamp to maintain a constant temperature, then the incubatoris more bother than it is worth. Therefore, find out the makes of incubators that are giving satisfaction in your own community, if you are intending to purchase one, and then send for one of a similar make. However, if you have not enough eggs to warrant purchasing one, then try to arrange with someone to loan you one, or to put your eggs in with some of theirs, so as to eliminate this expense.
There are in general two types of incubators, the hot water and the hot air, the latter being quite the more popular of the two. There are several different sizes of incubators, ranging from a fifty egg capacity up to a thousand egg capacity machine. An incubator with a hundred egg capacity is usually sufficiently large enough for the small poultry keeper. By running three or four hatches during the same season, a good number of chicks can be hatched.
There are a few requirements that must be fulfilled to realize the best results from an incubator. First and foremost, always follow the instructions that come with the incubator. The manufacturers of the incubator know more about their incubator than you do. Another thing that should be borne in mind is that youmust not expect every egg that is placed in the incubator to produce a chick. A very good hatch is about 75 per cent. Of course, this varies considerably, ranging all the way from nothing to as high as sometimes 100 per cent. Usually one can reasonably expect as high as a 60 per cent hatch, at least, and very often it goes considerably higher, according to the conditions under which it is run.
Moisture is a prime essential for the proper running of an incubator, and this should be provided for. If possible, arrange to run the incubator in a cellar, or some damp place. This can be aided, by sprinkling water on the floor, etc. Care must be exercised in running the incubator that fire is guarded against, and some insurance companies make special provisions in their policies for such occasions, and make a slightly higher charge for their policies, because of the danger.
Another essential condition for a successful hatch with the incubator is proper ventilation. Most machines are provided with something for the admission of fresh air. It is also necessary that the room containing the incubator be aired frequently to admit fresh air, but not insuch a manner that the eggs will become chilled, or that too much air will be admitted so as to carry off the moisture. Most incubators carry proper directions so as to provide against this danger.
The third condition necessary for proper running of the incubator is the maintenance of a constant temperature. It is usually advisable to have the temperature about 102 degrees F. the first week, 103 degrees the second week, and 104 degrees the third week. Any serious deviation from 103 degrees will result in a poor hatch.
Now, then we will conclude this chapter with a few pointers on running the incubator during the hatching period. It is always well to run the incubator a day or two empty, so as to get the idea of how to best maintain the required temperature. Clean the lamp thoroughly before running, and then during the hatch, always tend to the lamp after the eggs have been turned, and never before, because if the hands are smeared with kerosene, some of this is bound to be left on the shells, which will result in a poor hatch. Do not allow the lampto be in a draft, and clean the wick every day, so as to prevent the lamp from smoking.
After the first few days, the eggs should be turned at least once a day, and even better, twice a day. This is to imitate the mother hen, who does this on the nest. If the eggs are not turned, then the embryo of the chick will adhere to the shell of the egg, and either die, or be crippled beyond hope.
We must imitate the mother hen again in the artificial incubation of chicks, in regard to cooling. We saw in the previous chapter, how the hen leaves her nest occasionally to take food and water, with no ill effects on the hatch. Likewise we must cool the eggs in the incubator. This can usually best be accomplished while turning the eggs. Five or ten minutes a day are usually sufficient for the proper cooling, unless it is near the end of the hatch, when twenty or thirty minutes can be used for this purpose with safety.
On the seventh and the fourteenth day, it is a good plan to test the eggs in the incubator, so that the infertile eggs may be removed. This is done by a process known as candling. Hold each egg up in front of a light and notethe appearance of the interior of the egg. This can be done by making a hole in a box, that will fit over a light or lamp, and then holding the eggs up to the light, showing through the hole, which should be in line with the flame. If the egg appears clear, free from any dark spots, then the egg can be taken out of the incubator, as it is not fertile, and will not hatch. However, if the egg shows a dark spot, about the size of a bean, and you can detect small blood vessels running from it, then you may be assured that the egg is coming along in good shape, and will hatch out in due time.
With these points well in mind, one will have little difficulty in properly running an incubator, providing he has a reliable machine to begin with. Of the matters considered in this chapter, probably the most important factor of all is the constant maintenance of a uniform temperature. Now, then, let us consider that the chicks are pipping the shells and are ready to start out in life. We will therefore consider the care of the chicks in the next chapter, until they are able to care for themselves.