308 The Feeding of Animals 



straight to the conclusion that carbohydrates are milk 

 fat formers. The extent to which food fat assists 

 in the production of milk fat is not yet determined. 

 It cannot be safely asserted that the ingested fats do 

 not pass directly into the milk, but it seems quite 

 evident that the larger part of the glycerides of milk 

 have their origin in the animal. We are not sure, 

 either, whether protein is ever a source of milk fat, 

 but that it is a necessary source now seems quite im- 

 probable. 



The rate of formation of milk solids. A cow yield- 

 ing 6,000 pounds of average milk per year is not re- 

 garded as an unusual animal. This means, however, 

 the annual production of not less than 780 pounds of 

 milk -solids, an amount at least double the dry matter 

 in' the body of a cow weighing 900 pounds. When 

 we consider that this manufacture of new material is 

 carried on not only during a single year, but through 

 the entire adult life of the animal, we begin to realize 

 how extensive are the demands upon the food supply. 

 Still more striking is the case of high grade cows 

 yielding annually over half a ton of milk solids, and 

 when we remember the performance of Clothilde, whose 

 26,000 pounds of milk produced in one year certainly 

 contained more than 2,500 pounds of solid matter, we 

 must regard the cow as possessing wonderful powers 

 of transmutation. Her capacity for the rapid and eco- 

 nomical production of human food of the highest quality 

 is not equaled by an other animal. 



No facts could more forcibly illustrate the necessity 

 qf liberal and proper rations for the milch cow. 



