14 Bulletin 81 



data of analyses have been carefully reviewed ; the digestion coefficients 

 used are taken from the most complete and latest compilation of American 

 experiments' ; the convenience tables have been made so as to meet almost 

 any conceivable need ; and all the calculations and figures have been 

 checked and verified.' 2 It is felt therefore that these tables are adapted for 

 use in New England feeding practice. Maxima and minima are not in- 

 cluded, nor are sundry details as to the stage of growth of certain crops. 

 These are important items, but room for them is lacking. Such readers as 

 desire to note the variations in composition among fodders and feeds of the 

 same kind are referred to tables in Farmers' Bulletin 22 of the United 

 States department of agriculture ; and for similar variations in concen- 

 trates, to bulletins 78 and 82 of this station. 



III. FEEDING STANDARDS 



1. THE NATURE OF FEEDING STANDARDS 



Study of the sundry functions of the various nutrients shows that the 

 rapidly growing animal, the deep milking cow and the heavy fleeced sheep 

 need a liberal protein supply. It shows that the mature animal, kept with- 

 out gain or loss, or simply laying on fat, needs relatively less protein, but 

 much carbohydrates. Such study also shows that work consumes carbohy- 

 drates and fat, although using up muscle structure which can be built only 

 of protein. 



A knowledge of functions, however, furnishes no clue as to the proper 

 proportions of the sundry nutrients for the various purposes for which 

 stock is kept. And the next and obvious step is the determination of 

 these amounts and proportions. How much protein, carbohydrates and fat 

 and how much total food need be fed to the cow, the horse, the sheep or 

 the pig, that each may do its best ? What are the bodily needs of a given 

 animal; what food will meet these needs; how much and what nutrients will 

 maintain an animal without gain or loss ; and how shall maximum produc- 

 tion be attained at minimum expense? 



A vast amount of experimental work has been done in Europe and in 

 this country with a view of determining the fundamental laws of nutrition 

 upon which rests the economical practice of stock feeding. While results 

 of great value have been secured, our knowledge of underlying principles 

 is still imperfect, though yearly increasing. Its incomplete condition, how- 

 ever, does not preclude the use of such information as is at hand in the 



i Jordan & Hall : D. S. Dept. Agr., Of. Exp. Sta., Bui. 77(1900). 



2 Notwithstanding care errors are not unlikely to have crept in unobserved. The 

 writer will esteem it a kindness if any such are pointed out. 



