COLORADO FODDERS. 
5 
garding the relative value of the proteids in the two fodders, which, 
by the way, have high coefficients of digestion, 72.99 in the alfalfa, 
and 66.2 in the saltbush, and the probable absence of any deleterious 
substances having been made, there is left as the next important 
group, the substances represented by the nitrogen-free extract, which 
is divided into several parts, each of which, however, contains some 
proteids, except possibly the chlorin extract and the cellulose or 
residue. 
§ 9. The alcoholic extract represents these ' nitrogen-free 
substances in a large measure, but contains at the same time a large 
portion of the nitrogenous matter of the plant; the extract obtained 
by exhausting the hays with cold water and hot water with subsequent 
addition of malt extract are, taken together, of some moment, as they 
represent in round numbers one-tenth of the air-dried hay and usually 
show from fair to good coefficients of digestion; it is also true that 
the portion removed by treating the portion remaining after boiling 
with one per cent caustic soda, with chlorin, again heating with 
caustic soda and subsequently with a solution of sulfurous acid, may 
amount to a noticeable quantity, but its coefficient of digestion is al¬ 
ways low, often zero. So that the carbohydrates are practically di¬ 
vided into four parts, those soluble in alcohol, those soluble in muri¬ 
atic acid, those soluble in caustic soda and those which are insoluble. 
The value of this class of substance has always been recognized but 
in this work it is emphasized, particularly in the comparison of these 
two fodders, the alfalfa' hay and saltbush hay. In the former they 
are not only abundant in the alcoholic extract but they are also 
highly digestible; but this is not true of the other three important 
parts of the saltbush hay, i. e., the parts soluble in muriatic acid, 
caustic soda and that which is insoluble in any of the solvents used; 
these parts of alfalfa hay have high coefficients of digestion and the 
sheep gained in weight, but in the case of the saltbush hay they have 
low coefficients of digestion and the sheep lost in weight. 
§ 10. The great difference between these two fodders, alfalfa, 
an excellent one. and saltbush, a very poor one, lies in the character 
of the carbohydrates present in the two plants. While the proteids 
may be different, they are abundant in both plants and are both highly 
digestible. In this respect these two fodders are much more nearly 
alike than any other two fodders studied. This is fortunate for in 
regard to the quantity of proteids present and their digestibility, 
the hays are similar but the carbohydrates in three of the important 
portions of the plants are very unlike, though abundant in both plants, 
Thev are very difficultly digestible in the saltbush and required so 
much energy to effect their digestion that there was not enough 
appropriated from the fodder to do the work and carry on the animal 
functions without using some of that already stored in the body, 
therefore the animals lost flesh. 
§ II. The large amount of proteids digested in each instance 
and their high coefficients of digestion are tacitly assumed to be pre¬ 
sumptive evidence that they yielded more energy to the animals than 
