EXPERIMENT STATION RECORD. 



Vol. IX. No. 2. 



The .abstract of an article on fattening calves (p. 169) is of special in- 

 terest, since comparatively few investigations of this nature have been 

 made. In discussions of the nutrition of a young calf Soxhlet, who 

 published his work in 1 878, is usually cited. He made an extended study 

 of metabolism with three calves. The food and excretory products were 

 carefully analyzed and the respiratory products were measured with a 

 respiration apparatus of the Pettenkofer-Voit type. Soxhlet's experi- 

 ments were reported in a publication of comparatively limited circula- 

 tion, and are usually cited from more or less complete abstracts in more 

 available journals. 



Among the conclusions reached were that a sucking calf closely 

 resembles a carnivorous animal in that its diet consists of animal food 

 with an abundance of protein and fat, the time of digestion is short, 

 and the food is almost completely digested. In the amount of nitrogen 

 and carbon consumed the calf resembles a well nourished carnivorous 

 animal, and in the quantity of protein metabolized and not excreted it 

 resembles a fasting carnivorous animal. The sucking calf was found 

 to consume the same quantity of dry matter and one and a half times 

 as much protein as a full-grown herbivorous animal (sheep) of the same 

 weight with a very abundant diet — for instance, a fattening ration; but 

 it metabolizes, i. e., excretes, as little protein as an herbivorous animal 

 on a maintenance ration. In the adult animal under all circumstances 

 by far the larger part of the protein of the food is transformed into 

 easily decomposable "circulating protein," but in the calf only a very 

 small part. Also, in an adult animal the protein metabolized is at all 

 times greater than the gain of protein, or, in other words, the larger 

 part of the protein of the food is transformed into circulating protein 

 and the smaller part into protein of tissue; in the sucking calf the 

 reverse was found true, since the protein stored is always larger than 

 the protein metabolized, two-thirds of the protein of the food becoming 

 protein of tissue and one-third circulating protein. A very much greater 

 quantity of mineral matter is retained by the sucking calf than by the 

 adult animal. 



From the results obtained in these experiments Soxhlet computed the 

 food consumed and the metabolic balance for a calf two or three weeks 



101 



