No. e. DEPARTMENT OF AGRICULTURE. 293 



Here (Fig. 3) we have pictures of au experiment in which we under- 

 took to find out what it would mean to the farmer if he would select 

 rigidly in the fall of the year pullets that were of strong heavy body, 

 robust constitution, as compared to some that were more of a delicate 

 type as you see them here. (Fig. 4). Here (Fig. 3j is a pen of 25 

 pullets of strong vitality and here (Fig. 4) are 25 of weak vitality, and 

 yet there is not a sick chicken in the bunch. No chicken was kept in 

 this experiment that a farmer would not expect to keep. We kept 

 records of these flocks for the year, counting the cost of food, eggs laid, 

 and results of hatcbiug the eggs and rearing the chickens and we did 

 the same thing with the other experiments and compared the results 

 for two years since with the succeeding generations. 1 will give you 

 briefly the net results. These pullets of strong vitality, (Fig. 3) in 

 their first year of laying gave us a profit of 4Uc apiece more than the 

 flock here, (Fig. 4). They laid 11-i eggs apiece more. The eggs were 

 more fertile; they had strength and hatched better; the chickens 

 lived better, and in the fall of the year when we brought them up at 

 about six months of age and weighed the pullets and ])h()tograi)hed 

 them we found that the pullets (Fig. 5 A) that we hatched from the 

 eggs laid by hens of higher vitality weighed one-half a pound apiece 

 on the average more than these pullets (Fig. 5 li I of the same age, 

 hatched the same, in the same incubator and brooder, hatched from 

 eggs laid by the hens of low vitality. It was purely a (luestiou of in- 

 heritance of high vitality and low vitality and made a great ditference 

 in the results in dollars and cents. 



Here (Fig. 6) we have something that will illustrate the points bet- 

 ter than I have explained them. These verticle lines mark oft" the dif- 

 ferent months of the years into 13 periods of 4 weeks each. These 

 lines here mark off the distance, the percentage of egg production by 

 the different flocks, and you will see that the solid line is above the 

 dotted line, the heavy one being for the high vitality and the dotted 

 one for the eggs of low vitality, indicating a marked contrast in pro- 

 duction between the two. Notice the difterence in weight. The hens 

 of high vitality average higher. Also you will notice that they made 

 a better use of the feed that they consumed for the eggs thai rhey i)ro- 

 duced. And the same thing is true of pullets that were hatched I'rora 

 the hens of high vitality. You will see the same increases in the second 

 generation as you found in the first in the matter of egg i)rodHCii.'m ; 

 the same general difference of weight of the second generation as 

 there was in the first, and the same proi)ortionate gain in favor of the 

 more economical use of the feed ; showing that the hens in good health 

 made better use of their food than the others did. 



We go now to the other end of the cycle of lil'e. beginning with the 

 difference in characters that would indicate high and low vigor of the 

 breeding stock. Now let us examine tlie eggs and we will find that 

 we can actually tell the high vitality chicken before it ever gets out 

 of the shell. For exam])le. we took some trap-nested eggs from one of 

 the flocks and incubated them, a certain nniubcr from each hen, and 

 separated them out, the high vitality and thg low vitality germs on 

 the seventh day of incubation when the little embyro chicks were of 

 the size of a little red spot in the eii;g; nevertheless the size indicated 

 that there was a ditferpnce in vitality at that early stage. These eggs 

 were marked and then incubated and the last few days of incubation 

 were separated. This picture (Fig. 7) represents what we found. Of 



