Essay on the Interpretation of Milk Records. 17l 



These results are compared in the following diagram : — 



Fig. 7. — Mean R.M. and Lactation Totals for Cows Calving at 



differknt times of the tear. 



R.M. 1,418 records. Totals 731 records. 



R.M. Totals. 



Qts. Galls. 



15 720 



14 670 



13 620 



12 570 



11 



520 

 470 



Jan. Feb. Mar. Apl. May. June. July. Aug. Sept. Oct. Nov. Dec. 



The full corrections necessary to bring the monthly means 

 within a quart of one another were used on the 110 cows in 

 the same way as the corrections for age, but were found to 

 increase the range. Evidently normal variation or possibly 

 other factors are responsible for some of the differences in the 

 monthly means. Various modifications of these corrections 

 were tried however, and the following system was found to 

 reduce the range : — 



Cows calving in April and May . Deduct 5 per cent, from R.M. 

 „ „ July . Add 5 „ to „ 



„ „ August . . ,, 10 ,, ,, „ 



