B. WHY CONCENTRATED FEEDS ARE FED. 



Most of the home-grown coarse feeds are high in carbohydrates, 

 low in protein, and comparatively indigestible. Nearly all of the 

 concentrated feeds are very digestible and a large number are high 

 in protein and low to medium in carbohydrates. The concentrated 

 feeds are fed with the home-grown coarse feeds therefore, first to 

 increase the digestible matter, and second to increase the amount of pro- 

 tein in the daily ratioti. 



An illustration. Many experiments have demonstrated that an 

 average-sized new milch cow producing 12 to 15 quarts of milk daily 

 needs approximately the following quantities of digestible nutrients: 



Digestible: Protein. Fat. Carbohydrates. Total. 



Pounds, 2.0 to 2.5 0.5 13.0 16.0 



Now if the animal should be fed as much as she could consume of 

 a good quality of hay, (30 pounds) she would have at her disposal : 



Digestible: Protein. Fat. Carbohydrates. Total. 



Pounds, 1.4 .30 12.6 14.3 



This ration is deficient both in total nutrients and protein, for the 

 reason that the hay lacks protein and has comparatively a low diges- 

 tibility. If 7 pounds of the hay were replaced by an equal 

 quantity of corn meal, the 23 pounds of hay and corn meal would 

 furnish : 



Digestible: Protein. Fat. Carbohydrates. Total. 



Pounds, 1.5 .46 14.3 16.3 



The corn meal being a very digestible, but a one-sided or starchy 



feed, has sufficiently increased the total digestible daily nutrients, but 



not the protein. 



If 4 pounds of corn meal were replaced by 2 pounds of wheat bran 



and 2 pounds of cottonseed meal, the hay and several grains would 



supply : 



Digestible : Protein. Fat. Carbohydrates. Total. 



Pounds, 2.30 .70 12.8 15.8 



The addition of 3 pounds of corn meal rich in digestible starchy 

 matter, and 4 pounds of bran and cottonseed meal rich in digestible 

 protein, to the 23 pounds of hay, have furnished the required quan- 

 tities of total digestible matter and digestible protein. 



