VENTILATION AND MOISTURE IN INCUBATORS. 



The Greatest Problem in Successful Artificial Incubation Is In Ventilation and Moisture— The Egg Contains a Proper 

 Proportion of Elements to Build Up the Embryonic Structure— Death of the Embryo 

 Follows Abuse of Nature's Laws. 



By H. E. Moss 



, NE o£ the anomalies in the incubator business of to- 

 day is the diversity of treatment to which eggs are 

 required to be subjected under the instructions 

 of the makers of the various machines now on the 

 market and their ability to furnish pages of testimonials in 

 support of their claims of the merits of their particular 

 machine. There can be but one correct process or method 

 of incubation, and that is nature's method. If we would 

 duplicate nature we must conform to her method. I have 

 before me thirty catalogues from as many different incuba- 

 tor manufacturers. I have been examining these books and 

 comparing the claims and theories of the different makers 



Two Incubator Houses la Vse on an English Poultry Farm. 



I 



-SO far as they pertain to the essential requirements of a suc- 

 cessful hatcher. There is but one point upon which they 

 all agree, and than is the proper incubating temperature. 

 The ease with which this fact can be determined accounts 

 for this, but there are other conditions besides temperature 

 upon which successful hatching depends, and in these they 

 not only advance contrary theories, but in some instances 

 proclaim them as self-evident truths. Turning and cooling 

 the eggs are provided for In various ways, some even going 

 fio far as to furnish a cooling schedule for each day of the 

 hatch, each one differing from the other. It is not with this 

 question, however, that I propose to deal at this time, but 

 the one embraced in ventilation and moisture. 



We are told very emphatically by some that at the end 

 of a certain day the egg must show an air space to corre- 

 spond with a given diagi-am, and at the end of certain otber 

 days it must show certain other fixed lines of air space, 

 and that If the eggs are placed In warm water on a certain 

 day and they float with an exposed surface equal to a silver 

 quarter in size, the evaporation is right. Now this may all 



be approximately correct and agree with normal conditions, 

 but they go further and say that if they are found deficient 

 the ventilation must be increased and if excessive it must be 

 diminished and moisture Introduced. 



This sounds very plausible to the unthinking or those 

 who jump at conclusions. That all eggs lose a certain 

 amount of moisture during incubation is very apparent, but 

 the question is how do they lose it? From the rules they 

 lay down for the purpose of increasing or diminishing the 

 air space, we must assume their hypothesis to be that there 

 is a certain amount of water created in the egg that does 

 not belong there and that the Creator made the incubating 

 body a party to the reproductive process, and did not create 

 a perfect egg in a perfect condition to reproduce the species 

 without the intervention of this outside agency to rear- 

 range, as it were, its contents. 



The absurdity of such an hypothesis is apparent. 



Can we imagine for one moment that in His infinite 

 wisdom He would establish any incomplete or imperfect 

 thing, or law, as must be Inferred in this case, whereby 

 some species are taught to deposit their eggs in suitable 

 locations and never see them afterward, and that such eggs 

 should not contain the proper proportions of all the ele- 

 ments neces.sary to build up the embryonic structure? No, 

 we cannot conceive of any such condition. "We must assume 

 that whatever is placed within the egg is necessary to the 

 perfect development of its germ, and that if we wish to Incu- 

 bate it successfully we must not rob it of any one element 

 or any part of one, and that if we do it suffers in conse- 

 quence and in proportion to the degree of abuse to which we 

 /Subject it. 

 / It has taken a number of years for incubator makers 

 and operators to correct their ventilation. Carbon dioxide 

 has been a bugbear. They find they need no longer fear 

 this. They now unintentionally cease robbing the egg of its 

 moisture and realize the fact that under the new conditions 

 the hatches approximate natural methods. The moisture 

 pan is now a back number. The only benefit it ever worked 

 was to partially equalize the aqueous tension between the 

 inner and outer air, a condition which need not exist In a 

 modern incubator. A current of cold air drawn in through 

 the ventilating flues increases its capacity for moisture In 

 proportion to the increase in its temperature. Its relative 

 humidity being lower than the outer air, it gathers mois- 

 ture from the eggs in sufficient quantity to restore the equi- 

 librium. The allantois is robbed of its fluid and the mem- 

 brane becomes dry, destroying its function as a respiratory 

 organ, and death of the embryo follows. The greatest mor- 

 tality from this cause occurs during the third week. 



The ventilating flues and forced drafts with which many 

 machines of to-day are equipped are wrong In principle, al- 

 though It is possible to operate fairly well with them, pro- 

 vided the apertures are reduced to the minimum and em- 

 ployed solely foT "the TUTPOse of maintaining the air pure In 



