INCUBATION AND BROODING 



ing two or three feet above the floor level will, if of sufficient 

 capacity, maintain a constant change of air; simply because 

 there will be twenty degrees of difference in the specific gravity 

 of the interior and the exterior. The lighter air, together with 

 the diffused impure gases floating therein, would be forced out 

 of the room by the pressure of the superior air of the external 

 atmosphere. Obviously, then, there is no difficulty in keeping 

 the incubator room right in cold weather. The trouble is when 

 the external atmosphere registers seventy degrees and the room 

 also seventy degrees, there is then no margin of difference in the 

 specific gravity, hence the air becomes stagnant. 



To increase the temperature of the room beyond seventy 

 degrees would be wrong, bec{iuse it would reduce the circulating 

 power of the ventilating system of the incubators. One of the 

 foremost incubator manufacturers puts eighty degrees as the 

 maximum temperature in which his machine should work, giv- 

 ing the machine twenty-two degrees of working power. While 

 an incubator will give fair results under such conditions, we know 

 by actual test that it will do very much better when the room 

 is kept down to seventy degrees. We therefore lay down what 

 will, sooner or later, come to be observed as a general rule, 

 namely, that a building erected especially for incubators, shall 



A FRESH AIR BROODER 



Our brooder house, as will be seen by the illustration (Fig 

 1), is designed on the "progressive" plan with forty-two pens. 

 The chicks are put in at one end, and pass from pen to pen daily, 

 and come out at the other end when six weeks old. Let us point 

 out wherein we believe many brooder houses are wrong: They 

 do not provide sufficient space to enable the chicks to obtain 

 proper exercise during bad weather, and they do not provide 

 enough fresh air. The chicks are too often coddled and pam- 

 pered as if they were exotics, and are kept in a hot house tem- 

 perature. Such a system is not well calculated to produce a 

 large percentage of healthy chicks. 



We know that chickens have lungs for the purpose of 

 breathing in the air to gain its oxygen. These lungs in their 

 size, their coatings and their rapidity of respiration are adapted 

 to an atmosphere of pure air. If we fail to supply this aU our 

 efforts in other directions are rendered futile. Fresh air is one 

 of nature's most bountiful gifts, and yet xmtold numbers of 

 chickens perish every year for the want of it. We have dem- 

 onstrated with the large pipe brooder at South Dartmouth, 

 Mass., that "infant mortality" is wholly preventable. Chicks 



FIG. 2-SECTION OF BROODER HOUSE SHOWING CANVAS SHELTER IN SOUTH FRONT AND 

 WINDOW NEAR THE PEAK OF THE BROODING SECTION OF THE HOUSE 



be so constructed and ventilated that its variations shall be 

 restricted between fifty and seventy degrees. In such a room 

 with machines well adjusted, all other conditions being about 

 right, incubation wiU become a mathematical certainty. 



How are we to keep the room down to seventy degrees and 

 at the same time constantly change the air? That is the pro- 

 blem. There is only one way by which circulation of the aii- is 

 carried out by the natural forces set in play by temperature 

 changes without mechanical adjuncts of any sort, and that is, 

 to apply artificial heat to the exhaust flue. Increase the tem- 

 perature of the exhaust flue to ninety degrees and we have a 

 working gravity margin of twenty degrees. 



In our plan this is accomplished without cost and without 

 labor. We construct the exhaust flue of metal and lead into, 

 and carry up inside of it, the smoke stack of the brooder house 

 heater, and so utilize heat that is usually wasted. During the 

 first hatch of the season the heater will not be working. That, 

 however, will be early in the season when the external atmos- 

 phere is low enough. The end of the hatching season is the 

 time when this is needed, and then the brooder will be running 

 fuU blast, and the air in that exhaust flue will have a velocity 

 equal to the smoke inside of it. By reference to the plan of the 

 incubator room, shown in the ground plan, the fresh air duct 

 will be seen at the north end of the room, and the exhaust flue 

 is over the doorway at the opposite end. 



were taken direct from the incubator and put under hot water 

 pipes, without fringed hovers, in boods of fifty. Those chicks 

 reached the age of two months — long past the "mortality" 

 period — and there was never a sick chick among them, much 

 less a dead one. That, however, is an expensive plant, built 

 for a perpetual output of broilers. Ordinarily the pipe system 

 is a little risky for baby chicks during the first few days. A 

 cheap heater naturally bums low during the night and the tem- 

 perature in the brooders necessarily drops just enough to chill 

 the youngsters, but not enough to be felt by them after they 

 are a week old. 



The brooder house we illustrate is intended only for breed- 

 ing stock, to be used from about the middle of March. When 

 chicks are not required earlier than the middle of March un- 

 doubtedly outdoor brooders produce the hardiest stock; that is 

 to say, those that survive all the hardships and perils that 

 chicken life is heir to are perfect specimens of hardiness. We 

 want the hardiness of the outdoor brooder chick, but we do not 

 want the accidental losses, and we do not want the trouble. 

 We, therefore, planned our brooder house with this end in view, 

 and we have so far demonstrated that we are on the right side. 

 We have run a flock of sixty-six chicks and never had a day's 

 sickness. Two came to a violent death by cats or rats, while 

 all the others are perfect specimens of what six months' chickens 

 should be, and the pullets have, been laying for a month past. 



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