1020 EXPERIMENT STATION RECORD. 



The miuiinum quantity of albuminoids required to replace the daily 

 waste of the body, judging from the French experiments, must be 

 extremely small. The 3 horses observed by Grandeau received, on an 

 average, 0.538 lb. of digestible albuminoids per 1,000 lbs. live weight 

 daily. But there is evidence that this is not the minimum amount, for 

 one horse averaged only 0.447 lb. of digestible albuminoids per 1,000 

 lbs. live weight during 2 months, and gained 5 lbs. in weight; and 

 in another case the same horse gained somewhat on a ration of 0.37 lb. 

 of digestible albuminoids. In view of the data at hand, the autlior is 

 inclined to regard about 0.45 lb. of digestible albuminoids per 1,000 lbs. 

 live weight as the minimum quantity per diem for the maintenance 

 ration of a horse. This makes the nutritive ratio very wide; in the 

 case of the horse cited above it was only 1:12.8. 



"Miintz studied the digestive functions of the horse by killing 2 of little value a 

 few hours after they had been fed, and analyzing the contents of the stomach and of 

 successive portions of the intestines separately. One horse had been fed on hay 

 and one on wheat bran. It appeared that all ready-formed sugar was absorbed in the 

 stomach. Starch did not disappear in the stomach; it is digested subsequently by 

 the pancreatic juice. When the food consisted wholly of bran, more than half of 

 the albuminoids and a consiflerable proportion of the cellulose disappeared in the 

 stomach; but when the food consisted of hay, no assimilation of albuminoids, and 

 scarcely any of cellular matter, took place in the stomach. It is difficult to tell 

 what occurs shortly after leaving the stomach, owing to the large quantity of digest- 

 ive fluids (Itile and pancreatic juice) which are poured into the canal. The largest 

 amount of absorption apparently occurs in the large intestines and colon, and it is 

 here that the most striking diminution takes place in the various cellulose constit- 

 uents." 



In this connection the effect of labor on digestion, as shown byTiran- 

 deau and Leclerc's experiments, is interesting. 



"Taking the mean of a very large number of experiments with different diets, and 

 taking the proportion of organic matter digested while at rest as 1,000, we have the 

 following series of figures as representing the proportion digested during dilfereut 

 degrees of labor : 



Relative proportion of food digested. 



At rest 1, 000 



Walking exercise 1, 032 



At work walking 1, 007 



Trotting 976 



At work trotting 973 



At work in cab 959 



"We see here that the moderate exercise is accompanied by a small but distinct 

 improvement in the digestive functions, but that as soon as trotting cominenci s 

 digestion becomes less efficient than when at rest, while hard work while trotting 

 Btill further diminishes the proportion of food digested. When we look into tlie 

 details we find that the starch and sugar in the food are perfectly digested umler ;'ll 

 conditions of labor. The digestibility of the fat increases with exercise and docs 

 not diminish by labor below the point reached in repose. The digestibility of tlie 

 albuminoids increases rather considerably with exercise and diminishes shar|>ly when 

 trotting commences. The princij)a} matters usually grouped as 'soluble carboh\- 

 drates,' but which in this case are merely the more digestible constituents of the 



