Feeding Standards. 231 



Conditions affecting digestibility. Animals differ in their 

 power of digesting any given food or food constituent. For ex- 

 ample, the ruminants, by their more thorough arul repeated mas- 

 tication, are better able to digest bulky fodder than are pigs and 

 horses. This is illustrated in the following table taken from 

 Jordan : 



Dry Substance Digested from Meadow Hay (Per Cent). 



Samples Best Medium Poor 



Sheep 42 67 61. 55 - 



Oxen 10 67 64 56 



Horses 18 58 50 46 



On the other hand the power of digesting bulky feeds by dif- 

 ferent classes of ruminants is very similar. Steers have been 

 compared with sheep, and cows with goats, with no uniform dif- 

 ference in their digestive power for this class of feeds. 



With the grains, the differences in digestibility with the various 

 classes of farm animals are not greatly unlike. Comparative 

 trials of oats with sheep and the horse gave nearly identical di- 

 gestibility of the dry matter. With cows the result was similar. 

 In other trials where beans were used the advantage was slightly 

 with the ruminant. Swine digest the concentrated feeds as com- 

 pletely as do ruminants or the horse. Nor are they incapable of 

 digesting vegetable fiber when presented in a favorable condi- 

 tion. Pigs fed on green oats and vetch digested 48.9 per cent 

 of the fiber supplied. However, the digestive apparatus of the 

 pig is not adapted for dealing successfully with bulky fodder. 



So far as the influence of breed is concerned, this does not be- 

 come a factor in the digestibility of feeds. A Jersey is as effi- 

 cient in this capacity as a Holstein. Young animals appear to 

 digest as efficiently as older ones of the same species. There are, 

 very probably, differences in individuals, but the data so far 

 collected do not definitely show this. 



The influence of quantity of food on digestion is an unsettled 

 point. The old experiments of Wolff indicated that a full ration 

 was as completely digested as a scanty one. More recent ex- 



