170 PHYSIOLOGY OF THE DOMESTIC ANIMALS. 



average of 37.2 pounds, the common legal weight being 32 pounds to the 

 bushel. 



Of the group of hordeum (barley) various representatives are useful 

 as green fodder, but more especially their grains and straw. The com- 

 position of barley-grains is greatly modified by the locality of growth 

 and mode of cultivation. The following represents about the average 

 composition : — 



Solids 86.2 per cent. 



Nitrogenous bodies, 11-2 



Fats 2 -i ;; 



Non-nitrogenous bodies 65.5 



Cellulose, ....... 5-3 



Ash 2.2 " 



The protcids of barley consist in a large part of gluten-casein, 

 gluten-fibrin, mucedin, and albumen. No gluten can be obtained from 

 barley-meal. The carbo-hydrates consist of starch, from 1 to 2^ per cent, 

 sugar, and 1 to 7 per cent, dextrin. The digestibility of the barley-grain 

 is placed by Wolff as follows : — 



Ruminants. Horses. Hogs. 



Proteids, . . 77 per cent. 80.3 per cent. 78.2 per cent. 



Fats, . . 100 " 42.4 " 68.4 " 



Carbo-hydrates, 87 " 87.3 " 90.0 " 



The barley grains are, therefore, readily digestible, and in the form 

 of meal form a food of the first class in nutritive properties for cattle, 

 and are especially valued for the good influence which they exert on the 

 quality and quantity of the milk and butter. For horses also they may 

 be used to a certain extent as a substitute for oats, given in the entire 

 form, mixed with chopped straw. To old horses or foals, on the other 

 f hand, barley should be given as meal, or after being crushed. It has 

 been stated that if the barley-grains are swallowed whole they swell up 

 in the stomach, and may produce serious colic. Therefore, the animals 

 should receive water about half an hour before being fed with barley- 

 grains. The Arabs make Use of barley almost solely as food for their 

 horses, and administer it in the entire condition. Barley-meal has the 

 following composition : — 



Solids 87.7 per cent. 



Proteids, 11.6 



Fats 3.6 " 



Carbo-hydrates, 52 " 



Cellulose, 14.3 



Ash, 6.2 



Barley-meal is frequently adulterated with various mineral sub- 

 stances, such as clay, chalk, or plaster, which may cause it to prove 

 hurtful. Such adulterations may, however, be readily recognized by 

 microscopic examination. Barley-straw, especially, as is often the case, 



