20 



MAINE AGRICULTURAL EXPERIMENT STATION. 



ing principle of progeny test is playing no part in the breed- 

 ing of the herd. Without this principle in active operation the 

 breeder is in much the circumstances of a mariner without a 

 compass. Progress towards a desired goal is possible, but it 

 is likely to be by a very roundabout and haphazard route, and 

 is sure to be very slow. 



It is a matter of considerable interest to examine statistically 

 the age of breeding cattle in the hands of progressive Maine 

 farmers and breeders. Data on this point are presented in 

 Table 8. It should be noted particularly that all ages recorded 

 in this table are the ages of the animals at the time when they 

 were bred successfully. Each entry in the table is based upon 

 what we call a "completed record." Such a completed record 

 comprises, on the one hand, a service record, and on the other 

 hand a birth record, w'hich sets forth the facts regarding the 

 calf born as a result of the service accounted for on the ser- 

 vice record. The ages tabled here are the ages at the time of 

 service. 



The more important biometric constants from this table are 

 shown in Table 9. 



TABLE 8. 



Shozving the Age in Years of Cattle Used as Breeders. 





a. Bulls Used 

 AS Breeders. 



h. Cows Which 



Have Dropped One 



OR More Calves. 



c. Heifers Bred 



FOR Their First 



Calves. 



d. All Females 

 (6 + c). _ 



03 

 >> 



.s 



< 





I 





C3 

 (3 



|1h 





IP 



IS 







1 



2 

 3 

 4 



213 



252 



209 



149 



52 



53 



24 



8 



3 



22.03 



26.06 



21 .61 



15.41 



5.78 



5.48 



2.48 



.83 



.31 



4 



83 



138 



101 



80 



69 



66 



44 



44 



33 



22 



13 



9 



.56 



11.66 



19.38 



14.19 



11.24 



9.69 



9.27 



6.18 



6.18 



4.63 



3.09 



1.83 



1.26 



69 



92 



5 



41.57 



55.42 



3.01 



73 



173 



143 



101 



80 



69 



66 



44 



44 



33 



22 



13 



9 



8.31 

 19.93 

 16.29 

 11.50 



5 







9.11 



6 







7.86 



7 







7.52 



8 







5.01 



9 







5.01 



10 







3.76 



11 











2.51 



12 



4 



.41 







1.48 



13 







1.03 



14 













15 







2 

 2 

 1 

 1 



.28 

 .28 

 .14 

 .14 







2 

 2 

 1 



1 



.23 



16 











.23 



17 











.11 



18 











.11 















Total 



96710 



100.00 



712 



100.00 



166 



100.00 



87810 



100.00 



10 The reason for the discrepancy between these two figures lies in the fact that on 89 

 out of the 967 blanks there was a failure on the part of the breeder to record the cow's age. 



