530 



fore, as fair to conclude that in the case of these two materials the fat 

 ordinarily present does not render the albuminoid materials less digest- 

 ible. 



Action of amides and ammonium salts in the animal economy. — A summary, 

 byH. Weiske {J our 71./. Landw., oS (iSdO), p. 137). — Many vegetable materi- 

 als used as food for herbivorous animals contain amide bodies, prominent 

 among which is asparagiu. Feeding experiments by Weiske* showed 

 that when asparagiu was added to a ration rich in carbohydrates and 

 poor in albuminoids, it acted as an albuminoid economizer, that is, took 

 the place of a certain amount of albuminoids in nourishing the body. 

 Thus, sheej) which on a ration of hay, starch, and sugar stored in the 

 body respectively 0.27 and 0.279 grams of nitrogen each per day, stored 

 1.38 and 1.948 grams of nitrogen when asparagiu was added to the feed, 

 and 2.427 and 1.668 grams when the asparagiu was rej^laced by i)ea8 

 furnishing an equal amount of nitrogen iu the feed. In experiments 

 with goats, there was no falling off in either the quantity or quality of 

 the milk or in the live weight of the animal when a part of the albu- 

 minoids of the feed were replaced by asparagiu, but when carbohydrates 

 were fed in place of the asparagiu, changes were at once noticeable. 

 M. Schrodtt obtained similar results in experiments with milch cows. 



From experiments with rabbits N. Zuntz and P. Bahlmann| found 

 asparagiu capable of economizing the albuminoids, and J. Potthaft§ con- 

 cluded that asparagiu is a true nutrient, which by its combustion in 

 the organism saves the material of the body from consumption. 



In experiments by F. Rohmann || on the formation of glycogen, 

 rabbits were fed a ration poor in albuminoids but rich in carbohydrates, 

 to which asparagiu, glycin, ammonia salts, etc., were added. The animals 

 which received these materials in addition to the regular ration formed 

 considerably more glycogen than those fed carbohydrates alone; and 

 the action of asparagiu, glycin, and ammonia salts was about equal in 

 this respect. Kohmann suggested that since asparagiu breaks up in 

 the animal organism, forming ammonia, and since the above experi- 

 ments have shown that ammonia salts act in the same manner as aspar- 

 agiu iu the formation of glycogen, it is, therefore, safe to conclude that in 

 the metabolism ammonia salts possess the same action in economizing 

 the albuminoids that asparagiu does. 



The author (H. Weiske) doubts this economic action of ammonia salts, 

 as numerous experiments have shown that the feeding of ammonia 

 salts is accompanied by a decided increase in the breaking down of the 

 albuminoid bodies, and have never indicated that the salts economized 

 the consumption of the albuminoids in. the nutrition of the animal. 



* Zeitsch. f. Biologie, Bd. 15, pp. 2G1-296; aud Bd. 17, pp. 413-500. 



tMittheil. d. laud- u. milcliwiitschaftlicbeu Verancbs-Station iu Kiel, Heft 7, 1883. 



t Verbaiulluugeu d. pbysiolog. Gesellscbaft zu Berlin voiu 7 Juli, 1882, 



§ Ai'cbiv. f. d. gesanunte Physiologie, Bd. 32, p. 280. 



U Ibid., Bd. 3t), p. 21. 



