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organs are less liable to.suffer under domestication, than are those of the 
herbivorous animals. 
The little tadpole feeds upon vegetable matter, and he has a very long 
intestinal tract ; but when he becomes metamorphosed into a frog, which is a 
carnivorous creature, the digestive canal is transformed also, and the 
‘intestines become much shorter. 
Professor Williams points out the important fact that easily-digested 
food taken by animals in excess is liable to derange the smaller intestines, 
whereas coarser and more indigestible food containing much woody fibre, as 
over-ripe hay, rye grass, and coarse straw, is more apt to accumulate in the 
large intestines, causing disordered action, inflammation, or even paralysis 
of the intestinal muscular tissues. Boiled food also is apt to be retained in 
the stomach, and if given in excess may cause distension, inflammation, 
paralysis, and even rupture. It is not only the bad quality of the food, 
which may set up disorders in the alimentary tract ; but irregularity in diet, 
and full feeding after exhausting work, are also very liable to induce disease. 
The average capacity of the stomach in a horse of ordinary size, is from 
three to three and a half gallons; but it varies greatly according to the bulk 
of the animal, its breed, and the nature of its food. Relatively, it is more 
considerable in more coarsely bred horses, and in the ass and mule. When 
empty, its average weight is between three and four pounds (Chauveau), The 
accompanying picture shows the general shape of the stomach of the horse. 
The left hand opening is that of the gullet. That of the intestine is on the 
weader’s right. 
