1230 Rural Sciiuol Leaflet 



study of the cow evidences of constitutional weakness should be looked 

 for carefully. 



After this preliminary study of form, quality, and constitution has 

 been made, the cow should be studied in detail as outlined by the score 

 card. 



In general the ability of a cow to produce milk will be indicated by her 

 strength of constitution, her capacity to utilize large amounts of food, 

 and by a large, flexible, uniform udder ca])able of j^roducing much milk. 



Judging. — In judging a ring of three or more cows in order to decide 

 how they compare with each other, the score card is seldom vised, but 

 the things learned from the score card are remembered and used as a 

 basis of determining the good and bad points of the animals. Later 

 they may be scored if desired to check the judgments made, or some 

 expert dairyman may be asked to give his judgment. After much practice 

 one can learn to choose the best-producing animals with a fair degree 

 of accuracy. 



IX. THE BABCOCK TEST FOR BUTTER-FAT IN MILK 



R. A. Pearson 



The Babcock test is a quick and accurate method of determining the 

 richness of milk, which means its percentage of fat. 



Materials. — The materials needed arc: a hand-power centrifugal tester, 

 at least two milk test-bottles (Fig. i), one pipette in which to measure 

 the milk (Fig. 2), one acid measure (Fig. 3), one dairy thermometer, 

 about one pint of sulfuric acid with specific gravity between. 1.8 2 and 

 1.83, a few ounces of milk, and some hot water. All the necessary appa- 

 ratus and acid can be bought for from six to seven dollars from any dairy 

 supply company. They can be ordered through a hardware dealer. 

 Sulfuric acid is sold also at drug stores. 



Sampling the milk. — The milk to be tested should be thoroughly mixed 

 just before the sample is taken, so as to make sure that the fat, or cream, is 

 evenly distributed. This can best be done by gently pouring it back 

 and forth between two vessels several times. The temperature of the milk 

 should be between 60° and 70° F. 



Place the small end of the pipette at the center of the milk and suck 

 the milk up above the 17.6-c.c. mark. Quickly place the index finger over 

 the upper end of the pipette, and by releasing the pressure allow the 

 milk to run out until its upper surface is even with the 1 7.6-c.c. mark when 

 the pipette is held straight up and down. 



Place the point of the pipette a short distance into the neck of the 

 test bottle, holding it against the glass with both pipette and bottle at 

 an angle (Fig. 4). Remove the finger so as to allow the milk to flow 



