52 



Feeds and Feeding. 



total dry and organic matter, mineral matter, non-nitrogenous 

 constituents, protein and fat stored in a fat pig in one of their 

 experiments, for each 100 pounds of these constituents consumed 

 as food, with the results shown below. 



Substances stored, voided, etc., by a fattening pig for each 10O 

 pounds eaten Eothamsted Experiment Station. l 



In other experiments these investigators found from four ta 

 five times as much fat stored in the bodies of fattening pigs as 

 had been supplied in the food. In spite of the evidence accumu- 

 lated through this and other experiments, the view that fat may 

 be formed from carbohydrates was opposed by many scientists 

 until late years, but the question may now be considered settled. 

 Of the large number of experiments bearing on this most important 

 subject, only a few can be here noted. We select late contribu- 

 tions, in which all the precautions known to modern experimenters 

 in animal physiology have been observed. 



Kern 2 found that on an average at least 9,730 grams of fat had 

 been stored in the bodies of two full-grown fattening sheep during 

 70 days' feeding, and that only 6,872 grams could be accounted 

 for as the maximum amount formed from the digestible fat and 

 protein in the food combined. It thus appears that 2,858 grams, 

 or 29.4 per cent, of the total quantity of fat stored in the body, 

 must have been derived from carbohydrates. 



Soxhlet 3 fed three full-grown pigs of the same age for about 



1 On the Composition of Foods in Relation to Respiration, and the 

 Feeding of Animals, Report British Asso. f. Adv. of Science, 1852, p. 29; 

 Bui. 22, Office of Expt. Sta., pp. 235-82. 



2 Journ. f. Landw. 26, p. 549. 



3 Jahresb. Agr. Chemie, 1881, p. 434. 



