Testing Milk on Ike Farm. 149 



isfactory data as to the total production of milk and 

 butter fat of a cow may be obtained by making Qorrect 

 weighings and tests of her full day's milk once every 

 thirty days. 



i66a. Official tests of dairy cows. The various ex- 

 periment stations conduct tests of dairy cows for breed- 

 ers ami farmers, by which means records of production 

 of milk and butter fat are obtained for periods of 7 or 

 30 days, or for an entire year. This system of official 

 testing is described in bulletins issued by several sta- 

 tions.^ 



167. When to test a cow. The Vermont experi- 

 ment station for several years made a special study of 

 the question when a cow should be tested in order to. 

 give a correct idea of the whole year's production, when 

 only one or two tests are to be made during the lacta- 

 tion period.^ The results obtained may be briefly sum- 

 marized as follows: 



a. As to quality of milk produced. If two tests of 

 each cow's milk are to be made during the same lacta- 

 tion period, it is recommended to take composite sam- 

 ples at the intervals given below. 



FIRST SAMPLE SECOND SAMPLE 



For spring cows, j 6 weeks after calving, 6 V»-7 V' mos. after calving 

 For summer " 18 " " " '6 -7 " " 



For fall " S-10" " " 5io-7 " " 



If only one test is to be made, approximately correct 

 results may be obtained by testing the milk during the 



1 See, e. p.. Wis. exp. station bull. 191 and 242 : also bull. 226. The 

 Wisconsin Dairy Cow Competition, and research bull. 26, Studies In 

 Dairy Production, published by this station. 



"Sixth report, 1882, p. 106; Ninth report, ISO.'), p. 176. 



