300 FOODS AND FEEDING. XIII. 



receiving the drier food had access to a water trough. In 

 eight weeks the pen getting the wetter food increased by 

 3341b., while the other gained 4581b. (live weights). The pigs 

 of the former consumed 19041b. of food, while those of the 

 latter ate 2254R). The proportions of food consumed to 

 weight gained were 



In those getting much water ... 5'7 



In those getting little water ... 4*9 



The pigs fed on the drier food thus made 12411). more increase 

 in live weight and yielded about 102ft). more pork, while each 

 pound of increase in live weight was obtained by the expendi- 

 ture of O'Sff). of food less than with the other animals. The 

 extra food cost about 19/-, but the value of the increased 

 quantity of pork was about 42/6, leaving a net gain of 23/6 for 

 the pen receiving the drier food. 



Money Value of the Constituents of Food Stuffs. 



Attempts have been made to fix money values to the albumi- 

 noids, carbohydrates, and fat present in food stuffs, so as to 

 permit of the calculation of the value of a food from the re- 

 sults of its analysis, as has been done in the case of manures 

 (r. Chap. VIII.). 



The results of these attempts have not been entirely satis- 

 factory, nor indeed can they be expected to be, since many of 

 the most valuable properties of food stuffs, e.g., flavour or 

 palatibility, cannot satisfactorily be expressed quantitatively. 

 Samples of food of desirable flavour and much relished by 

 animals may often command a price much higher than could 

 be deduced from their composition. 



Wolff, long ago, deduced the ratios of the values of digestible 

 carbohydrates, fats, and protein in many concentrated food 

 stuffs at 1 : 3 : 2-4. 



Konig gave 1 : 2'9 : 2-7, while in various States of America 

 most discordant values w r ere obtained, possibly owing to great 

 local variations in prices, 



In 1891, a long paper was read before the Surveyors' Insti- 

 tute on the subject by Kinch.* He points out that the physio- 

 logical ratio of values of protein to carbohydrates would be 



* Abstract in J. Soe. Cheni. Ind. 1892, 701. 



