130 
PROF. JAMES LAW. 
Molly has gone on improving, but the others show a very 
decided falling off which is greater in the noninjected Freda than 
in the injected Daisy, and greater in the uninjected Bertha than 
in the injected Belva. 
Oscillations. The variations above and below the general 
average for each animal injected and not injected with tuberculin 
would be very clearly seen by glancing at the tables giving the 
graphic illustration 
which in figures may 
for two Holstein’s and 
be shown as follows : 
lbs. 
two Jersey’s, and 
lbs. lbs. 
Belva, 
General average per day 37.247 
Highest per day 42.25 
Lowest 31.50 
Freda, 
44 u 
“ 41.78. 
4 4 4 4 
57 - 5 ° 
“ 34 - 5 ° 
Daisy, 
44 4 4 
“ 18.26. 
4 4 4 4 
22.25 
I 5 - 
Bertha, 
4 4 4 4 
“ 27.01. 
4 4 4 4 
23 - 5 - 
“ 23. 
Molly, 
4 4 4 4 
“ 41.19. 
4 4 4 4 
48. 
“ 33 - 5 - 
The extreme it will be observed were actually greater for 
the cows that were not treated with tuberculin than for those so 
treated. Among the Holstein’s ,'Belva had a variation amount¬ 
ing to 10.75 ^s., Freda one of 13 lbs., and Molly one of 14.5 lbs. 
Among the Jersey’s, Daisy had a variation of 7.25 lbs, and 
Bertha one of 10.5 lbs. Extreme variations in the yield of milk 
then cannot be charged on the action of a test dose of tubercu¬ 
lin injected into a healthy animal, nor of a series of such test 
doses administered at intervals of a week. 
PERCENTAGE OF BUTTER-FAT IN THE MILK. 
Before dismissing the milk it is desirable to consider how the 
ratio of butter-fat is affected by repeated test doses of tuberculin 
injected into a healthy animal. A study of the tables given 
below will fail to establish any connection between the presence 
of a test dose of the tuberculin in the animal body, and any in¬ 
crease or diminution of the fat in the milk. The Holstein Belva 
had the highest percentage of butter-fat (3.6) October 20th, ten 
days before the first injection of tuberculin. Her next highest 
record (3.4) was December 8th, while under the action of tuber¬ 
culin. Her lowest record (2.8) was December 1st. two days 
after the operation of a dose of tuberculin. Her variation (0.8) 
