436 PHYSIOLOGY OF THE DOMESTIC ANIMALS. 



giving certain food for its traces to disappear from the faeces. In the calf 

 three days were required for the removal of traces of a previous meal of 

 barley, while four days 'were required for an ox under the same condi- 

 tions. In the sheep fed with hay, it has been determined that the food 

 remains 20 hours in the first three stomachs, and in the fourth stomach 

 1.2 hours; in small intestine, 2.3 hours; in caecum, 7 hours; and in colon, 

 5.5 hours; or, in all, 36 hours before appearing as faeces. 



Carnivora fed on pure flesh diet produced but little faeces. A dog 

 weighing thirty-five kilos, and fed with a half to two and a half kilos of 

 meat, produces from twenty-seven to forty grammes of faeces, in which 

 there will be only nine to twenty-one grammes of solids ; therefore it 

 may be said that with a flesh diet only 1 per cent, of the amount of solids 

 taken with the food escapes from the body in the form of faeces. 



Omnivora form considerably larger amounts of faeces. Animals 

 living on a mixed animal and vegetable diet, like man, will pass daily 

 about one hundred and thirty grammes of faeces, containing thirty-four 

 grammes of solids, which will represent about 5 per cent, of the solids 

 taken as food. When the vegetable diet is in excess, this may rise to 

 13 per cent., so that only seven-eighths of the solids are finally absorbed. 

 Hogs pass in their faeces only about 20 per cent, of mixed matter taken 

 in food. However, when fed on sour milk, with beans and peas, only 

 about 1 per cent, escapes absorption. So, also, according to Wolff, pigs 

 digest almost completely the residue remaining after making meat ex- 

 tracts. The hog is able to digest both vegetable and animal matter, 

 and is claimed to be capable of digesting fully 50 per cent, of cellulose. 



The following table gives the percentage of constituents absorbed in 

 hogs fed with sour milk : 



Albumen, 96.06 percent. 



Non-nitrogenous substances, . . .98.90 " 

 Inorganic matter, 64.46 " 



So, also, of the following vegetable foods, the figures indicate the 

 amount digested and absorbed : 



Horse-beans, 

 Peas, . 

 Oats, . 

 Barley, 

 Rye, . 



99.8 per cent. 

 99.7 " 

 98.7 " 

 92.7 " 

 90.7 " 



The largest amount of faeces is formed by the herbivorous animals. 

 In the horse and ox, of one hundred parts of food about 40 per cent., as 

 a rule, escapes unchanged in the faeces, so that only three-fifths of the 

 food swallowed serves any nutritive purpose. This follows from the 

 fact that a large part of vegetable food is absolutely indigestible, and all 

 is very difficult of digestion. The horse, as a rule, digests a smaller pro- 

 portion of dry fodder than does the ox. 



