982 



EXPEKIMENT STATION RECORD. 



oaring for birds in small numbers in coops is greater than in earing for an 'equal 

 number in a house and yard. The results are so pronounced that the author regards 

 them as conclusive. 



The fact is also pointed out that larger gains were made on the ration containing 

 skim milk, and also that gains were more economically made by the young than the 

 older chickens. 



ExperimenU in incubation (pp. 18-25). — The effect of storing eggs inclosed cases 

 and in the open air, storing at different temperatures, and allowing them to remain 

 for a time undisturbed, i. e., "resting" the eggs before incubation, was tested, as 

 well as the time required after mating to insure fertility, the duration of fertility, and 

 the relative fertility of eggs of different shapes. The following table summarizes 

 some of the results obtained : 



Effect of storing eggs in different v)ays. 



Number of 

 ejgs incu- 

 bated. 



Number of I Number of 

 chicks eggs infer- 

 hatched. i tile. 



Number of 



Number of 



Pffffsin whipb r^^s in which 



development 

 stopped by 



the 12th day 

 of incuba- 

 tion. 



development 

 stopped be- 

 tween 12th 



and 20th days 

 of incuba- 

 tion. 



Eggs stored in closed cases 



Eggs stored in open air 



Eggs stored at 70° F 



Eggs stored at 50° F 



Eggs rested before incubating 



Eggs not rested before incubating 



A test made with year-old Plymouth Rocks showed that eggs became fertile very 

 soon after mating commenced. The cockerel was put in the pen with the hens in the 

 evening and it is not probable that he mated with any hen until daylight the next 

 morning, yet the eggs laid by 2 of the hens not more than 40 hours after mating 

 yielded vigorous chicks. 



To learn how long the fertility of eggs continues after mating has been discon- 

 tinued the cockerel was removed from a pen of year-old Plymouth Rocks. The eggs 

 laid bj' the 20 hens during the next 13 days were incubated. Eight eggs laid on the 

 last day of the test jdelded 3 good chicks. Of the 27 eggs laid during the first 3 days 

 after the removal of the male, 10 yielded chicks. The 30 eggs laid on the last 

 3 days of the test yielded 7 chicks. 



The results show diminished fertility, but it is evident that longer test periods are 

 needed to determine the limits of its duration after mating. The work is to be 

 continued. 



Of 25 eggs of normal shajie, 8 hatched and 9 were infertile. From the same num- 

 ber of very long eggs 9 chickens were hatched, 12 of the eggs i^roving infertile. 

 From 25 short, roundish eggs 7 chickens were hatched, 8 eggs proving infertile. 

 In the first case, 3 chickens died in the shell when well grown and 5 by the tenth 

 day of inculpation. Similar values for the long eggs were 2 and 2, and for the short, 

 roundish 7 and 3. 



Breeding for egg production (pp. 26-40). — The tests begun at the station several 

 years ago on the possibility of breeding hens of superior egg-producing qualities 

 (E. S. R., 12, p. 586) were continued. The results, which are reported in detail, 

 led to the following conclusions: 



"During the 3 years in which we have been selecting breeding stock by use of the 

 trap nests we have found 30 hens that laid between 200 and 251 eggs each in a year. 

 Twenty-six of them are now in our breeding pens and constitute — until other addi- 



