POULTRY – KEEPING.

New Zealand Journal of Agriculture, Volume XV, Issue 2, 20 August 1917, Page 103

POULTRY - KEEPING.

F. C. Brown,

Chief Poultry Instructor

INCUBATION

On all up-to-date plants September is one of the busiest months of the year, for it is then that the bulk of the chickens must be incubated if they are to have sufficient stamina to withstand the heat of summer and make satisfactory development by the time' the dear-egg season arrives. To those who use artificial means for hatching, the question of. securing the desired number of chickens at the right time is a simple- matter. On the other hand, where the natural mother has to be depended upon probably more trouble will be experienced, than ever before in securing the necessary broody hens. Even with the heavier breeds the object of the successful breeder is to . eliminate as far as possible the broody, propensity- from his fowls, and the more this is reached the harder it is to obtain settinghens, especially at the time they are most required. The up-to-date poultryman realizes that if eggs are to be produced in the greatest number it will not pay him to have birds which will go broody .just because they are required for the hatching of chicks. The one and only solution of the problem is the adoption.' of artificial' methods. The difficulties of working an incubator are often exaggerated. Practically any one with the ordinary amount of intelligence can make at least a fair success of the work. Of course, in order to obtain the

best results a reliable make of machine must be used. There are dozens of different makes of incubators on the market, some of which are reliable but others not. ' Before purchasing an incubator the beginner would be well advised to consult a man of experience, not only with a view to securing a good make. of machine, but also to be given a practical lesson on its working. This is not to say that the manufacturer's instructions should be departed from, but rather that a practical demonstration be given as to the right way of applying them. • .

Temperature, Ventilation, and Moisture.

With so many different styles of machines, and such a variation in the methods of providing the necessary -temperature, ventilation, and moisture, it is impossible to lay down any general rule that will suit all alike. There are certain rules, however, which will apply to all kinds of incubators, and the observance of which is essential to success. The most important is that prescribing the maintenance of an even temperature—lo2° F. for the first, week, 103° for the second and third weeks, and 104° to 105° when hatching. The temperature should be taken at the level of the tops of the eggs on the tray ; . in other words, the bulb of the thermometer should be resting on a fertile egg. Moisture and ventilation are important factors in the management of incubators. There can be no set rule as to how and when these should be applied' that will suit all .machines and. climates alike.Climatic conditions have a considerable influence in artificial hatching, and these must be studied and the system of management .amended accordingly. As a general rule, if the air-cell dries down in accordance with the diagram supplied with the usual book of instructions it may be taken for granted that the desired ventilation and moisture are being obtained. The determination of the correct amount of' ventilation and moisture required can only be decided -by an experienced operator when examining the air-cell. It is sometimes stated that the size of the air-cell gives no guide whatever to successful incubation or to the correct amount of ventilation and moisture required. Neither it does, unless the operator thoroughly understands it. It is usually advised that when the air-cell is considered to be too small at any given time the ventilators should be opened wider, and if the cell be larger the opposite course should 'be taken, or the ventilation reduced. This rule, however, does not always work out right in actual practice. For instance, • sometimes it may be observed that the air-cell is . slow in coming down, but this does not necessarily mean that the egg contains too much moisture. This condition may be solely due to the chicken growing too fast and its normal size practically filling the shell. The trouble of “dead in shell” at about the pipping -stage is undoubtedly the most vexed problem that the poultryman has to solve. The condition of the breeding-stock. is very often responsible for heavy losses in this respect. Instances. could, however, be multiplied where, the breeding-stock have been in the pink of condition, and yet a very high percentage of the chicks died in the shell when fully developed. Usually on breaking such eggs it will be observed that the chicken is so . .large that it cannot make the necessary movement to break the shell, and is consequently unable to get . out of its prison. The management of the air-cell is thus .seen to be a matter

of vital importance, for upon the operator knowing whether an egg contains an excess of moisture - or whether it holds an abnormalsized chick depends largely the success or otherwise of the incubation process.

When it is found on testing the eggs that the air-cell is too small, and the eggs appear to be more or.less clear just’ under the line of the air-cell, this usually indicates that an excess of moisture is present and that the ventilators should be opened wide to allow it to escape. On the other hand, if the cell is considered to .. be too small and the egg appears to be dark right up to the membrane dividing the air-cell it indicates that the chick is growing too fast, and will probably be too large at the pipping-stage for it to be able to give its natural turn to break .the shell. When this condition is observed it goes to show that too much oxygen is being supplied, which causes the chick to grow at too rapid a' rate. To prevent this the only safeguard is to reduce the ventilation-space. In some climates, in order to have the air-cell down to the desired line the vents have to be kept nearly closed right up to the time of pipping. Of course, just before the eggs commence to pip, and until the hatch is cleaned up, the ventilators should be opened wider, as fresh air is an essential at this stage of the incubation process.

Naturally there are other things to be observed indicating a probable reason for the failure of eggs to hatch. Sometimes sufficient moisture has not been present in the machine, and the membrane (or skin on the inside of the shell) is so tough that the chick cannot pierce it, and consequently dies. This is also a common cause of crippled chicks being hatched; Through , the chick being too long in the shell, and the constant working to get out, the delicate legs are injured. Even where chicks fail to hatch it will frequently be found on close examination that the hock-joints are in a more or less inflamed condition through no other cause. - ' . • ' ,

Care of the Lamp.

This is a matter of great importance, not only in regard to securing a good hatch, . but in minimizing the risk of fire. Scores of incubators have been burnt, as well as buildings, all for the want of giving, the lamp careful attention.. Provided the lamp is properly looked after, there is no more danger of it getting on fire than any ordinary houselamp. It should be filled, trimmed, and cleaned each morning after turning the eggs, and when the machine has risen to its normal temperature. Do not turn the flame up . high enough to smoke, or soot will collect in the flue. ' Never use a wick which does ’ not properly fit the burner, or difficulty will be experienced in maintaining an even temperature. The lamp should be filled on hatching-day as on other days. > • .

Turning and Cooling the Eggs.

After . the eggs have been in the incubator for forty-eight hours they should be turned twice a day. The object of turning the eggs is to change their relative position, so as to prevent the germ from sticking against the shell. It is not necessary that the eggs be given a complete half-turn. A few extra rolls will, do more good than harm. The eggs should be moved gently for the first few days, so as not to

injure the embryo. It is always a good plan to have a regular time for turning the eggs both morning and night. ’ Cease turning as soon as the eggs' commence to pip: • ' On each day after the , third the eggs should be cooled while turning them. It is .not possible to give the exact amount of cooling required, as the operator will have to be guided by the development of the air-cell. The longer the cooling under ordinary conditions the larger the air-cell becomes. As a general rule, ten minutes once a day for the first week is sufficient. The time may be increased gradually (according to climatic conditions) up to twenty minutes in the second week, and up to thirty minutes during the third week.

Hatching Out.

If . the eggs were fresh when placed , in the incubator, and the proper temperature has been maintained, the eggs should pip on the twentieth day, and be cleaned up on the twenty-first day. . On no account open the door of the incubator after the eggs have begun to pip.. The chicks should not be removed from the incubator until the twenty-second day. ■