Principles and Practice of Stock Feeding 5 



introduction 



No general statement as to the laws of nutrition and the results of ex- 

 perience in cattle feeding has been made in the publications of this sta- 

 tion since 1887. There is so much call for information on these matters 

 that it has been thought wise to attempt in some measure to meet the 

 demand by a popular presentation of present knowledge. The opportunity 

 to do this is afforded by the passage by the legislature of 1898 of a law 

 placing $1000 at the disposal of the station for printing. Had it not been 

 for this appropriation the publication of a bulletin so entirely devoid of the 

 results of original investigation, so purely a matter of compilation, would 

 hardly have been deemed a justifiable use of the national funds. The United 

 States appropriation is spent in accordance with the terms of the law for 

 investigation and research rather than in purveying general agricultural 

 information. 



The writer has tried to state matters clearly and so far as possible has 

 avoided the use of technical terms. Such as are used are defined. (See 

 pages 7 and 8, also glossary, pages 38-39). The reader is reminded, how- 

 ever, that the natural laws underlying stock feeding and man's experience 

 therein are not kindergarten subjects, but that careful study is needed if 

 their mastery is sought. No excuse is offered for the prominence given to 

 dairying. Examples and illustrations are all taken from dairying practice. 

 To cover all the branches of stock feeding would be to write a book. 



II. ANIMAL NUTRITION 



1. COMPOSITION OF THE ANIMAL BODY 



The animal body contains many complex substances but they may for 

 present purposes be grouped as follows : water, ash or mineral matter, pro- 

 tein, and fat. 



1. Water is the main constituent in point of quantity. It comprises 

 from 40 to 85 per cent of the gross weight, varying according to age and 

 condition. While indispensable to the life functions, water has but little 

 economic importance in this connection. 



2. jlsli (mineral matter, bony matter) is a term applied to the residue 

 or ashes left after complete burning. Bones contain much ash and other 

 tissues carry small quantities, making in all 2 to 5 per cent of the gross 

 weight. It is largely phosphate of lime. While obviously essential to 

 proper animal growth, ash exists in plentiful quantities in most rations and 

 hence, like water, may be dismissed from further consideration. 



3. Protein (the nutrient which forms flesh) is a term applied to a some- 

 what miscellaneous group of nutrients which are alike in that they all con- 

 tain from 12 to 19 per cent nitrogen. Three main sub-groups are rec- 

 ognized in animal proteins, the albuminoids, the gelatinoids (collagenes) 

 and the nitrogenous extractives. The albuminoids are the most im- 



