The vigor of the breeding stock, the manner in which it has been fed and managed, and the care given the eggs will determine to a high degree the hatchability of the eggs. An important measure of success in turkey raising is the number of fully matured turkeys raised in proportion to the number of hens in the breeding flock. An average of 25 mature birds raised per hen is considered very good in well-managed turkey flocks, whereas in most general-farm flocks 10 to 15 mature birds per hen would be a good average.
The period of incubation of turkey eggs is 28 days, and the method is much the same as that used with chicken eggs. Turkey eggs can be successfully hatched by turkey hens or chicken hens, or in incubators. Hatching in incubators is best and is coming into more general use, especially on farms and ranches where turkeys are raised in large numbers. Turkeys hatched and reared by hens, especially chicken hens, are likely to contract disease and become infested with parasites at an early age. Sitting turkey hens can cover from 15 to 18 eggs; chicken hens, from 7 to 10 eggs.
NATURAL INCUBATION
Hatching the eggs under turkey hens is widely practiced and is often the most practical method. When the turkey hen becomes broody and has remained consistently on the nest for 2 or 3 days, she should be given her eggs. If several turkey hens are sitting at the same time, care should be taken that each gets back into her own nest. Nests are most conveniently arranged on the ground, in boxes about 2 feet square or in barrels. If rats are a menace, the nest should furnish protection against them and should always be made proof against larger animals so that the turkey hens will not be disturbed or the eggs destroyed. The nests should be flat and shallow, as deep nests may result in crushed eggs or crushed baby poults. Nests with damp sod bottoms and only a little straw to keep the eggs from rolling into the corners are generally satisfactory. Nesting batteries in which each hen is provided with a small individual run so that she can get off and on the nest at will are very good. With this method the only care necessary is to see that feed and water are always before the hens and that each one remains broody. If individual runs are not provided, the hens should be taken off daily, allowed to exercise and eat, and then returned to their own nests. Plenty of water to drink and clean, wholesome grain feed, such as a mixture of wheat, oats, and corn, should be provided, and fresh green feed or good alfalfa hay should be made available.
Turkey or chicken hens, before being set on turkey eggs, should be treated with sodium fluoride, as previously directed.
ARTIFICIAL INCUBATION
Correct incubator temperatures are much the same for turkey eggs as for chicken eggs, but the greater size of the turkey eggs may necessitate some adjustment of the apparatus used in measuring the temperature. This is true in nearly all kinds of incubators except those of the forced-draft type. The relative position of the thermometer in the egg chamber is important in the accuracy with which it records the temperature. For hatching turkey eggs the proper position of the thermometer is usually indicated in the directions that are furnished by the manufacturer of the incubator. As a general rule, with the bottom of the bulb 17/8 inches above the egg tray, the thermometer should read 100.5° F. for the first week, 101.5° the second, 102.5° the third, and 103° the last week. Forced-draft incubators are usually run at about 99.5°. Temperature can best be regulated, however, by using the thermometer that goes with the machine, placing it in the position recommended by the manufacturer, and then following the manufacturer's instructions for hatching turkey eggs, making sure that the egg trays do not sag.
Turkey eggs lose about 3.5 percent less moisture during incubation than do chicken eggs, notwithstanding the fact that turkey eggs require about 7 days longer to hatch. Excellent hatches have been obtained when the loss of moisture based on the weight of the eggs just before they were set, ranged within the following limits: After 6 days of incubation, 2 to 8 percent; after 12 days of incubation. 4.1 to 6 percent; after 18 days of incubation, 6.2 to 9 percent; and after 24 days of incubation, 9 to 12 percent.
On this basis, a dozen turkey eggs of normal size should lose about 1 ounce for every 6 days of incubation. The air cells of turkey eggs are smaller in proportion to the size of the eggs than are those of chicken eggs because normal evaporation in turkey eggs during incubation is considerably less than that in chicken eggs. When more moisture is needed in the incubator it can be provided by putting in water pans, or by placing burlap wicks in the pans. When less moisture is needed the water pans may be removed or the ventilation increased.
As a rule the eggs should be turned at least 3 and preferably 4 to 6 times daily. Four times daily, every 6 hours, day and night, is an excellent plan. They should be tested preferably on the eighth or ninth and again on the twentieth to twenty-second days, and all infertile eggs and those having dead germs should be removed. Cooling the eggs once or twice a day until they feel slightly cool to the face may be of value in small incubators. Turning and cooling should be discontinued about the twenty-third day, and the incubator door should be darkened and kept closed until hatching is completed. The poults may then be left in the incubators for about 24 hours or else put in the brooder and fed as soon as hatching is completed and the poults thoroughly dried off. Poults held in the incubator should be kept at about 95° F. and should have a rough surface such as 1/4-inch-mesh hardware cloth to stand on. Keeping the incubator dark helps to keep the poults quiet and tends to prevent spraddle legs. There is no good reason for withholding feed longer than 24 hours. If feed is withheld for a much longer period when the poults are in the brooder, they may eat the litter. Therefore, poults should be fed when they are put in the brooder house.
Shipping day-old poults in specially built strawboard boxes has been found to be satisfactory. The container is larger than that ordinarily used for baby chicks, 60 poults commonly being placed in each box.
