FORTY-THIRD ANNUAL CONVENTION 211 



and care, as records of their production under the original con- 

 ditions are not available. 



Table 2 — Average Yearly Records of the Five Cows Nos. 7, 8, 9, 12 and 

 33, that Were Aged When They Came to the College Farm. 



Milk Fat 



§^ ^ ail ? a§l i^ 11 



^ : P B : PR S- : ts 



: >^ : ^ : : ^ 



1 



3790.9 





183.84 





$24.40 



23c 



2 



2802.3 



--26 



135.50 



-26 



18.64 



22c 



3 



2841.1 



-25 



141.60 



-23 



18.58 



22c 



Comparisons between tables I and II would indicate that 

 the decrease between the first and second and the second and 

 third lactation periods in the case of the old cows was due to 

 advancing age. It will be noted that the cost of feed per pound 

 of butterfat remained nearly constant for the three years and 

 did not fall below twenty-two cents per pound, while in the case 

 of the younger cows there was a greater decrease in cost. 



In table III the cows that were four years old or over when 

 they came to the farm are referred to as "original scrubs ;" those 

 that came as yearlings and calves, or wxre dropped on the college 

 farm, are designated as "developed scrubs," while the terms 

 Holstein x scrub, Guernsey x scrub and Jersey x scrub refer to 

 the first generation heifers out of scrub cows and by purebred 

 sires of those breeds. The comparisons are made between cows 

 falling into these different classes and in this table the younger 

 animals are not compared to their own dams but to all of the 

 old cows taken as a group. In the comparison between the dc^ 

 veloped scrubs and the originals it will be noticed that the former 

 have produced 13% more milk and 12% more butterfat while 

 little difference is noted in per cent of fat or length of lactation 

 period. With seven cows in each group and the number of lac- 

 tation periods, twenty-five and twenty-nine respectively, this in- 

 crease is worthy of note. A direct comparison cannot be made 



