1910.] Value of Records of Milk Yield of Cows. 469 



of Milk Regulations, 1901, made by the Board of Agricul- 

 ture, but it may happen that certain cows in a herd may give 

 milk which does not contain those percentages (3 per cent, 

 of butter-fat and 8*5 per cent, of other milk solids). This is 

 particularly liable to be the case where the milking is done 

 at unequal intervals. The seller of milk containing less than 

 these percentages runs a risk of being charged with a con- 

 travention of the Sale of Food and Drugs Acts. It is there- 

 fore of great importance to the milk-seller that he should 

 inform himself by testing at regular intervals (about once a 

 fortnight) whether the mixed milk of his cows is being 

 maintained at a satisfactory level of quality. The morning 

 and evening milking should be tested separately for this 

 purpose. In the event of this mixed sample falling danger- 

 ously near the percentages mentioned in the Sale of Milk 

 Regulations, he will need to take a sample of the milk of 

 each cow in order to identify the cows which are giving milk 

 of low quality. There is frequently great variation in the 

 composition of the morning and evening milk from the same 

 cow, but if no modification can be made in the hours of 

 milking, the milk of a cow which systematically gives poor 

 milk should not be sold unless mixed with a sufficient quantity 

 of rich milk to bring it well above the limits referred to 

 above. Experiments have shown that if a cow is well 

 nourished, no alteration or improvement in feeding will per- 

 manently alter the quality of her milk. 

 Where milk is used for butter-making it is essential that 

 I the dairyman should see that all his cows are yielding milk 

 with a high percentage of butter-fat, otherwise unless a very 

 high price is obtained for the butter the value obtained for 

 the milk is very low. For instance, 3*6 per cent, of fat in 

 the milk is equal to a butter ratio of 1 : 25 — that is, every 25 lb. 

 1 of milk will produce one of butter ; so that if the butter only 

 : fetches is. a pound, it represents less than 3d. a gallon for 

 i the milk. It is, therefore, of the highest importance to every 

 j butter-maker to see that each cow in the herd is producing 

 < milk of high quality. 



1 Arrangements have been made with most of the Agricul- 

 I tura l Colleges and Agricultural Departments of the Universi- 

 ties for determining the percentage of butter-fat for a fee of 



