Constitutional Vigor in Poultry 



613 



eluded. However, since those factors were the same for all comparison flocks, 

 it can be said that the above figures do represent the comparative profit. 



mortality 

 The mortality was a very variable factor throughout the experiments. 

 Although the total number of deaths was the same in the strong and weak 

 flocks, it by no means 



Pe,rcenl2f^c-o 1 z 3 4 5 e 7 b 9 ion n b 14 15 16 17 /& /.9 

 5rrong-78-78-?o\ 



maK-79-79-ZZ 



5fron^-76-7Q-ji 



mifk-7S-7S-/3 



3rror?J-2i-zHz 

 drron^-Al^- 

 FiG. 1 70. — The percentage of mortality. 



represents the real dif- 

 ference in the vigor of 

 the fowls. There were 

 several deaths due to 

 accident and others to 

 viciousness. Pens 21, 

 2 1 , and 1 2 (strong) were 

 the only strong flocks 

 where the mortality 

 totaled more than in 

 the corresponding weak 

 flocks. To all appear- 

 ances the Barred Plym- 

 outh Rocks in these strong flocks were much healthier and more vigor- 

 ous than those in the comparison weak flocks. The comparative total 

 percentage of mortality is shown in Fig. 170. 



incubation 

 In an experiment of this nature the hatching power of the eggs and 

 the economical reproduction and replacement of the flocks usually is of 



TABLE 39. Incubation Report 

 (All experiments) 



A II experiments 



