This is the appearance of an egg with a strong, live germ, which under favorable circumstances will produce a duck.
An egg that is not fertile on the sixth or seventh day will be perfectly clear and transparent; all such should be removed at once, as it is useless to allow them to remain. Another kind of egg often seen is a weak or imperfectly fertilized egg, and shows an irregularly-shaped blood vessel, which had started but lacked vitality enough to continue. Such an egg will not hatch and should also be removed from the nest or incubator. Frequently the germ in an egg will show life when tested on the seventh day, but lacks the vitality to carry it through, and when tested later will show dark, irregular blotches over the surface of the egg. These will not hatch, and should be taken out when noticed.
On the fourteenth day the little creature inside the egg begins to assume shape and show considerable life. It has increased many times in size since it was seen on the seventh day; the red veins have become more numerous and have spread over the entire surface, while the yolk is scarcely distinguishable from the other portions. The pupil of the eye has now become distinct, and the projection of the wings is clearly perceived. The absorption of the yolk has also commenced, and this will continue until the twenty-fourth day, when it will be nearly completed. The egg from this time on will rapidly grow opaque, and at the eighteenth or twentieth day is entirely so. On the twenty-fourth day the duckling is ready to make its way out of the shell, and in forty-eight hours after pipping the shell it will be entirely out.
NATURAL INCUBATION.
Hatching under the sitting hen (generally used for hatching ducks) is what is termed the natural process of incubation. The hatching of eggs by this means has always been followed, and no special skill is needed for success, provided the eggs are well fertilized with healthy germs. Many who raise ducks in large numbers, however, use almost exclusively artificial means; some use both the natural and the artificial, while others use the natural entirely.
Of the natural method we shall treat first: Hens of medium size of the American class, barred Plymouth Rocks and Wyandottes, are considered the best for sitting. Nine duck eggs are about the right number to place under a hen in early spring weather, but when the season is far advanced as many as thirteen are used. The hens should be provided with large, roomy nests, and slatted fronts that can be removed and replaced easily when the hens are fed and watered. The nesting material should be of hay or straw, and the nest should be slightly concaved; in the bottom place a little finely cut hay.
Before the hen is put on the eggs she should be thoroughly dusted with insecticides; the nest also should have a good dusting of the same. Both hen and nest should undergo a thorough dusting several times during the process of hatching as a safeguard against lice. When the ducklings are hatched they should also have their share of the insecticides before they are given to the hen. When a large number of sitting hens are used for hatching, as many as possible should be set at one time, and the ducklings raised in brooders. Hatching with hens may be done on a large scale and the young brooded artificially. As many as five hundred sitting hens are used on some farms for hatching ducks. They are set in small houses or rooms with the nests around the sides in tiers, each nest having its own lattice door. Each day, in the morning, the hens are taken from their nests and fed and watered on the floor of the room. They are taken down in limited numbers, sections, as it were, at a time, and after they have had the food, drink, and a little exercise they are placed back on the nests and another section is fed and watered.
ARTIFICIAL INCUBATION.
The subject of artificial incubation has engaged the attention of the civilized world for generations past; the method has done wonders for the poultry industry and has opened up the pathways to fortunes that might otherwise never have been made. The science of incubation and brooding has been developed wonderfully in this country during the last quarter of a century, and what seemed almost an impossibility then has indeed become a certainty now. There are many thousands of chicks and ducklings hatched by artificial means each year, and the numbers of good machines now being manufactured in this country at low prices make poultry raising a business that almost anyone with a limited capital may profitably engage in. The mission of an incubator is to supplant the sitting hen, and make it possible to hatch a large number of chicks at a minimum amount of cost and labor. That this can be done is proved each day.
For artificial incubation, have a room with a temperature as nearly uniform as possible. Balance the beat in the machines, or in other words, see that the heat is uniform at both ends, and, in fact, all over them. See that each is running steadily before placing the eggs in it, as there is a great deal in starting right. The machines should be run at a temperature of 102° for the first three weeks, and 103° the last week. The eggs should be turned twice each day at regular periods. Introduce a pan of water from the fifteenth to the twenty-second day, no matter what the location of the machine, whether in a damp cellar or in a dry room overhead, in a moist atmosphere near the seashore or in a dry one at an altitude in the country. The temperature may go as high as 101° just previous to and while hatching without injury. Place the glass on a live egg after the animal heat rises, which will be when the circulation begins. This will be perceptible in good eggs the fourteenth and fifteenth days.