122 AGRICULTURE OF MAIXE. 



Their functions in the body are many, namely, the production 

 of heat and energy, the formation of body fat, the protection of 

 the flesh of the body from too rapid breaking down as a result 

 of vital processes, the manufacture of non-nitrogenous organic 

 milk constituents, i. e., sugar and fat. These nutrients are 

 more directly comparable to the fuel which is used to run the 

 engine. They are burned in the body not only to keep it warm 

 but also to produce energy used in muscular motion and in the 

 vital activities of theT3ody. If an excess of these materials is 

 fed over what is needed for immediate use in keeping up the 

 temperature and producing energy it is stored away in the form 

 of body fat for future use. For the purpose of making energy 

 or producing heat there is a difference between these materials 

 we are considering together, that is, it has been found by actual 

 experiment, by actual burning, that fat will on the average 

 produce two and one-fourth times as much heat as the same 

 weight of carbohydrates, and this fact has to be taken into 

 consideration when considering the value of these materials. 



You will pardon me for considering somewhat in detail in a 

 more technical way than is desirable perhaps at a meeting of 

 this kind, the component parts of feeding stuffs, but it seemed 

 necessary in order to present what I wish to consider farther 

 on. 



TERMS USED IN MAKING UP RATIONS. 



Having considered briefly the nutrients contained in feeds 

 and fodders there are terms which are used in connection with 

 making up rations which may be familiar to you all as they 

 have been used for more than twenty-five years in the literature 

 on the subject. 



Digestible dry matter is a term applied to that portion of 

 the total dry matter of the food which is dissolved out bv the 

 digestive fluids in the alimentary tract of the animal and 

 becomes available as food. The digestible nutrients are likewise 

 that portion of the nutrients that are available as food. 



Digestion coefficients are the percentages of the various 

 nutrients in foods found to be digestible by actual experiments 

 with animals, and these factors are used to calculate the 



