8(j 



MASS. EXPERIMENT STATION BULLETIN 251 



Figure 5. — Average Monthly Prices Received for Eggs by Poultry Cooperators, 

 Years Ending October 31, 1926, and October 31, 1927. 



NOV DEC JAN. FEB, MAR APR MAY JUNE JULY AUG SEPT OCT 



A very close relationsliip also exi.sted between fall egg production and 

 total annual egg production. Table 15 shows this relationship for the 

 1927 records. Recent work by Hays and Sanborn^ shows that hatching 

 before April 15 tends to increase persistency and hence total annual egg 

 production. The relation shown in Table 15 probably results partly from 

 this tendency. It may also be due in part to the fact that poultrymen 

 with high laying strains of birds had earlier hatching dates and got their 

 birds into production earlier in the fall. 



Relative Importance of the Factors 



The relation between differences in labor return and diflferences in 

 each of the factors studied has been considered. It remains to point out 

 the relative significance of the several factors. This cannot be deter- 

 mined directly by comparing the tables showing the relation between each 

 factor and labor return per bird, because the units in which the factors 

 are expressed are not the same. 



The following table places the factors on a uniform basis with respect 

 to this diificulty by showing the effect on labor return of a change of a 

 unit of variation in each factor. 



' Hays, F. A. and Sanborn, Ruby. Annual Per.sistency in Relation to Winter and 

 Annual Egg Production. Mass. Agr. Expt. Sta. Te«b. Bui. 9, 1926. 



Intensity or Rate of Laying in Relation to Fecundity. Mass. 



Agr. Expt. Sta. Tech. Bui. 11, 1927. 



