196 POULTRY PRODUCTION 



hens for Rixt\- minutes daily durinij; tlie holding period, he 

 increased the innnl)er of vinort)us clucks }>y 10 i)er cent. 



He states that he "noticed fnrther in handling eggs in 

 incubators both years, that the embryos of the warmed 

 eggs, after being placed in the incnl)ator, presented a dis- 

 tinctly different appearance from those eggs not warmed, 

 being more clear cut, larger in size at the same period of 

 incubation, more acti\e, and giving every appearance of being 

 stronger and more vigorous. 



"Considering both tests, it seems apparent that tliere is no 

 particular gain to Ije secured from warming eggs that are 

 to be held for a period of not more than ten or twelve days, 

 although this rec|uires further investigation. Apparently 

 the vitality of the embryo suffers when held for a longer 

 period." 



Jackson suggests no practical method of warming eggs held 

 for hatching purposes, and no good method has been devised. 



A possible partial explanation of the above may be had 

 in the findings of Bushnell and Maurer,^ who report that 

 bacteria found in normal eggs do not develop readily at 

 blood (or incul)ating) temperatures, but do develop at ordi- 

 nary room temperatures. As they suggest, when eggs are 

 kept for hatching at ordinary temperatures, enough develop- 

 ment of the organisms may take place during the time 

 intervening between the laying of the eggs and their incuba- 

 tion, to bring aliout decomposition enough to injure the 

 delicate embryo chick by vitiating its food-supply. Infertile 

 eggs presumably frequently infected do not decompose when 

 kept at incubator temperatures for three weeks. 



Disinfecting Purchased Eggs. — 15ccause of the prevalence of 

 certain chick diseases, and the fact that their germs are found 

 adhering to the shells, some ])oultrymen are disinfecting 

 their eggs by dipping tliem in 02 per cent alcohol or in a 

 2 to 3 per cent solution of a standard stock dip. This is a 

 safe precaution in all cases where eggs are secured from 

 flocks with whose history one is not perfectly familiar. It is 

 unnecessary in cases where the eggs come from stock that 



1 Unpublished data of Kansas A^iicull ur:il Experiment Station. 



