The Nutritive Ratio 51 



amounrs of water, like fresh forage, silage, fruits, 

 roots, etc. So well is this recognized that many 

 dairymen find it economical to provide a regular sup- 

 ply of succulent foods for their cows in milk, even 

 though the nutrients in such foods cost more than 

 similar amounts would in the dry state. 



In all the studies and investigations that have 

 been made with respect to the nutrition of domestic 

 animals, no one has received more attention than the 

 relation of the proteid, or nitrogenous part of the 

 nutrients, to the non- protein part. Disregarding the 

 protein supply so far as the maintenance of the 

 animal is concerned (and a certain amount of protein, 

 as is well known, is requisite to maintain life), 

 there are considerable amounts of protein in the 

 milk, the most important being the casein and albu- 

 men of the milk, which together comprises more than 

 3 per cent of the milk or about 25 per cent of the 

 milk solids. This protein, of course, must come from 

 the protein supply in the food. The problem of fur- 

 nishing sufficient protein in dairy foods has been 

 greatly simplified by the introduction of certain by- 

 product commercial foods that are now abundant on 

 the markets, so that it is no longer difficult, nor 

 very expensive, to provide a sufficient amount of pro- 

 tein, and it is found that it is not necessary to "bal- 

 ance" the proteid and non -proteid nutrients so care- 

 fully as formerly. This balance is ordinarily ex- 

 pressed by the nutritive ratio, and a dairy ration is 

 now considered at least fairly satisfactory if the nutri- 

 tive ratio falls anvwhere between 1 : 4.5 and 1 : 6.5. 



