FARM MANURE 135 



The nitrogen, phosphoric acid, and potash in these 

 two rations are retained in the animal body in dis- 

 similar amounts ; 10 per cent, more of these elements 

 being retained from the more liberal ration, due to 

 more favorable conditions for growth. Making al- 

 lowance for this fact there will be present in the ma- 

 nure from the mixed feed one-half more nitrogen, and 

 two and one-half times as much phosphoric acid, as 

 in the manure from the timothy hay, which, _ free 

 from bedding, contains about 790 pounds of indigesti- 

 ble matter while the manure from the mixed feed con- 

 tains 760 pounds, the mixed ration being more digesti- 

 ble. If both manures contain the same amount of ab- 

 sorbents, the manure from the ton of mixed clover 

 and bran will weigh slightly less, but contain more 

 fertility than that from the timothy hay. 



The value of manure can be accurately determined 

 from the composition of the food consumed and 

 the care which the manure has received. Only a 

 small amount of the nitrogen in the food is retained 

 in the body. The larger portion is used for repair 

 purposes. The nitrogen of the tissues which have 

 been renewed is voided as urea in the liquid excre- 

 ments. Some of the nitrogenous compounds of the 

 food are utilized for the production of fat, in which 

 case the nitrogen is voided in the excrements. The 

 fact that but little of the nitrogen and mineral matter 

 of the food, under most conditions, is retained in the 

 body may be observed from the figures of Lawes and 

 Gilbert relating to the composition of the flesh added 

 to animals while undergoing the fattening process. 55 



