INFLUENCE OF THE PLANE OF NUTRITION UPON MILK 63 
These results are corroborated by a large number of data from 
other experimental animals which will not be given here. 
Other evidence on this point is found in the reports of 
official tests of dairy cattle as reported by the various breed 
associations. All interested in the practical phases of dairy 
husbandry are familiar with the immediate application which 
followed the publication of the factst regarding the possibility 
of increasing the richness of the milk by these means and the 
astonishing results that have been obtained in seven day tests 
of dairy cows in recent years as a result. It is well known 
that the great increase in butterfat yield in these tests is due 
largely to a decidedly higher fat percentage. For example 
ia 1903 the cow, Sadie Vale Concordia, held the Holstein 
butter fat record for seven days with a yield of 694.3 lbs. of 
milk containing 3.52 per cent of fat.* The record up to 1917 
is 730 lbs. milk containing 5.54 per cent of fat. At the 
same time there is no evidence of any appreciable raise in 
the average fat percentage for the breed. The average fat 
percentage reported by the Holstein Association for the 
highest twenty-five cows in seven day tests is 5.1. The aver- 
age for the highest twenty-five yearly records is 3.96. 
The practical use of this means of greatly increasing the 
butterfat production temporarily has resulted in an entirely 
new basis of fixing value for breeding stock among certain 
of the dairy breeds. 
The question may be raised whether it is not normal re- 
gardless of the state of flesh of the animal for the fat per- 
centage to be high during the first four weeks after parturition 
followed by a decline to a lower level. Data are also at hand 
showing this is not the case. In Table II are found data giving 
the fat content by weeks in the milk of cows that were in a 
moderate state of flesh at parturition. It will be noted that 
there is a constant rise in the fat percentage from the be- 
ginning and that the average for the year is decidedly higher 
4C, H. Eckles, 4 New Factor Influencing the Per Cent of Fat in Cows’ 
Milk in Hoard’s Dairyman, 40, 28, p. 696, Aug., 1909. 
6 Holstein Friesian Yearbook, 3, p. 93, 1903. 
® Hoard’s Dairyman, 48, 1, p. 14, Jan., 1917. 
