Part Five — The Sources of Feeds 



XXV. The Sources of Feeds 



THERE are three main lines of study in learning more 

 about feeding dairy cattle. 



I. We should learn all we can about" the principles 

 of nutrition which underHe all our practice. 



2. We must learn all we can about what Dr. Armsby calls 

 the "Materials of Nutrition", the feeds. 



3. We must learn all we can about the practice of feeding 

 itself. 



It is with the second paragraph that this series of articles 

 on the source of feeds will deal. We will try to teach some- 

 thing about the feeds that may be used in the feeding of 

 dairy cows and attendant young stock. 



RELATIVE VALUES 



It is impossible to teach about feeds unless something is 

 said about relative values. Whether one will use much 

 gluten feed in his ration or whether he will use cottonseed 

 meal depends largely on the relative value of these two feeds 

 for producing milk. The price per ton will not tell this 

 exactly even with these two feeds because there is less food 

 in one than in the other. In one ton of gluten feed there are 

 1614 pounds of total digestible nutrients and in one ton of 

 good cottonseed meal such as is on the market today, there 

 are 1496 pounds of total digestible nutrients. Therefore if 

 these two feeds both cost $66.00 per ton the advantage is 

 with the gluten feed because we would get more total diges- 

 tible nutrients for $1.00 in that feed. However, if one is 

 looking for protein to supplement other feeds and the prime 

 reason for buying the feed was to get the protein then he 

 might wish to get the cottonseed meal because in buying, a 

 ton of cottonseed meal one gets 632 pounds of digestible 

 crude protein while in buying a ton of gluten feed one gets 

 only 432 pounds. 



Therefore, one needs to study feeds carefully from two 

 or three points of view. 



I. From the point of view of the total digestible nutrients 

 because these are the measure of the total food value of the 

 particular feed in question. So long as there is enough 

 protein in the ration one pound of digestible crude protein 

 Page One Hundred Seven 



