Aug., 1923] INSPECTION OF FEEDING STUFFS 7 



We have this data for the pure grains and feeds, but 

 because the various proprietary feeds are not standardized 

 there are not data available for them. 



HOW TO USE TABLE NUMBER 3. 



Only the digestible nutrients are of value and so in 

 comparing two feeds v^^e should compare just the digestible 

 nutrients. Suppose we had a cottonseed meal which 

 analyzed 38 per cent, protein. The table shows cottonseed 

 protein to be 84 per cent, digestible. We then would have 

 84-100 of 38 lbs., or 31.9 lbs. of digestible protein per 100 

 pounds. If a wheat bran analyzed 15 per cent, protein we 

 see from the table that it is 78 per cent, digestible and we 

 would have 78-100 of 15 or 11.7 lbs. of digestible protein. 

 The cottonseed meal would have 31.9 lbs. compared with 

 11.7 in wheat bran. 



HOW TO FIGURE THE COMPARATIVE VALUE OF 



FEEDS FROM THE CHEMICAL ANALYSIS. 



Because such factors as palatability, quality of protein, 

 digestibility, etc., play an important part in determining the 

 value of feeding-stuffs it is difficult to make an exact com- 

 parison of their value from a chemical analysis. The 

 analysis will, however, serve as a very valuable guide. 

 Since the farmer can usually raise carbohydrates cheaper 

 than he can purchase them he is chiefly interested in buy- 

 ing the concentrated feeding-stuffs for their protein and 

 fat content. 



Feeds may be compared upon the basis of the number 

 of pounds of protein and fat one dollar will buy. An ex- 

 ample is as follows : Feed number 93 sells for $1.90 per 

 100 pounds and is guaranteed protein 8.50 per cent, and fat 

 3.50 per cent. If it contains 8.50 per cent, protein there 

 are 8.50 pounds of protein in 100 pounds of feed costing 

 $1.90. Then one dollar will buy 8.50 divided by 1.90 or 

 4.5 pounds of protein and 3.50 divided by 1.90 or 1.8 pounds 



