VII. METHODS FOR THE ANALYSIS OF CATTLE FOODS. 



1. Preparation of Sample. Official. 



Grind the sample so that it will pass through a sieve having circular holes 

 1 min in diameter. In case the sample can not be ground reduce it to as tine 

 a state as possible. 



2. Moisture. Official. 



Dry the substance according to the directions given under " VI. General 

 Methods," page 38. 



3. Ash. Official. 



Determine as directed under " VI. General Methods," page 38. 



4. Nitrogenous Bodies, 

 (a) CRUDE PROTEIN OB TOTAL NITROGENOUS BODIES. OFFICIAL. 



Determine nitrogen by the Kjeldahl or Gunning method, as directed under 

 " I. Fertilizers," page 5, and multiply the result by 6.25. 



(b) PURE PROTEIN OB ALBUMINOID BODIES. OFFICIAL. 



Determine the albuminoid nitrogen according to the directions given under 

 " VI. General Methods," page 38, and multiply the result by 6.25. 



(c) AMIDO NITROGEN. OFFICIAL. 



Subtract the amount of albuminoid nitrogen from the amount of total nitrogen 

 to obtain the amido nitrogen. 



5. Crude Fat or Ether Extract. Official. 

 Determine by the direct method under " VI. General Methods," page 39. 



6. Sugars, 

 (a) PREPARATION OF SOLUTION. PROVISIONAL, 



Weigh into a flask or bottle, suitable for stirring or shaking, 10 to 20 grams 

 of the material, depending upon the amount of soluble carbohydrates present. 

 Add 250 cc of ice-cold water, less the volume of water present as moisture in 

 the material, and stir or shake for four hours. If enzymatic action is feared, 

 the extraction should be made at a low temperature, preferably by surrounding 

 the extraction flask with broken ice ; or extract at ordinary temperature with 40 

 to 50 per cent alcohol. If there is present in the material much soluble sub- 

 stance, correction should also be made for the increase in volume due to solu- 

 tion. If necessary for clear filtration, add from 5 to 10 cc of alumina cream, 

 prepared as directed under " VI. General Methods," page 40, just before filter- 



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