52 



Soy beans mature their seed and yield 1200 to 1500 pounds (20 

 to 25 bushels)' per acre. The seed is very digestible and the above 

 yield will furnish 1,000 pounds of digestible organic matter, of which 

 one-half will be digestible protein. Fifteen hundred pounds of cot- 

 tonseed meal will furnish a like amount of digestible organic matter 

 and protein,- which at present market prices has a value of $25. 

 Inasmuch as the soy bean straw has no feeding value, the yield ot 

 fifteen hundred pounds of beans to the acre would not be considered 

 sufficient to warrant the growing of the seed for feeding purposes. 

 It is believed therefore, that under present conditions it will prove 

 more economical as a rule for dairymen possessing satisfactory 

 markets and railroad facilities, to purchase their protein in the form 

 of high grade concentrates, rather than to attempt to grow it in the 

 form of soy bean forage or seed. 



In spite of the fact that it is possible by the aid of 

 What Kinds of clover, peas and similar crops to produce considera- 



Grain shall ble protein upon the farm, the Massachusetts dairy- 

 the Dairyman man will still find it necessary to purchase no small 

 buy ? amount of grain if the dairy herd is to be kept in a 



profitable working condition. 



The chief and most economical sources of protein are to be found 

 in the form of cottonseed and linseed meals, glutens, distillers' and 

 brewers' dried grains, malt sprouts, bran and middlings, — by-products 

 from the oil, glucose, beer, whiskey and flour industries. Generally 

 speaking the higher the protein percentage in the feed the more eco- 

 nomical it is as a source of protein. Thus by making a reasonable 

 allowance for the value of the starchy matter and fat, cottonseed 

 meal is generally the cheapest source of protein, followed in succes- 

 sion by gluten feed, distillers' grains, brewers' grains, flour mid- 

 dlings, standard middlings and bran. This order is not always 

 likely to hold true because of market fluctuations. Bran while rela- 

 tively expensive as a source of nutrition, is valuable as a diluter or 

 distributer of the heavy concentrates, and as a slight laxative. 



Corn, hominy and barley meals are about equally nutritious, and 

 the most economical carbohydrates. Since the average farmer pro- 



1. A legal bushel is ;8 lbs. 



2. Brooks has pointed out (Sixth report of this station pp. 13-14) that soy bean meal 

 produced rather more milk and a better quality of butter than cottonseed meal. Like quan- 

 tities of the two meals however niuit have somewhat similar values for the purposes of 

 nutrition. 



