r 



FEEDING OF ANIMALS. 313 



in Germany and elsewhere, both with pigs and with rumi- 

 nants, to elucidate the point ; and when the conditions of the 

 experiments were suited to the object, the results contributed 

 to the re-establishment of the conclusion that the carbo- 

 hydrates play a very direct and important part in the fat- 

 formation of the animals of the farm. 



Further, in the edition of Wolff's work published in 1888, Wolff and 

 he almost unreservedly admits the rdle of the carbohydrates ^V^Sr 

 in the formation of at least a great part of the fat not only of opinions. 

 pigs but of ruminants. Indeed, some years previously, Voit 

 himself had made substantial concessions on the point. 1 



It happens, however, that about 1880 Dr Armsby, now the Armsby's 

 Director of the Agricultural Experiment Station at the Penn- JJjJJJ 1 of 

 sylvauia State College, published a work which has since Feeding. 

 passed through several editions, entitled Manual of Cattle- 

 Feeding ; a Treatise on the Laws of Animal Nutrition and 

 the Chemistry of Feeding-Stuffs in their application to the 

 Feeding of Farm- Animals, which was a very good digest, 

 chiefly of the work done in Germany, on the subject. 



So far as the question of the sources of fat is concerned, it 

 gives numerous tabular illustrations from Voit's work ; and 

 it follows almost exclusively the views of Voit and of Wolff 

 at that time. He, however, quotes results obtained both 

 with pigs and with other animals, which, he admitted, indi- 

 cate, according to the figures, the formation of fat from the 

 carbohydrates. But he considered that the data at command 

 were not sufficient to solve the problem; and, with Wolff, 

 assumed that the question could not be satisfactorily settled 

 without experiments in a respiration apparatus. He also 

 considered that estimates founded on the composition of 

 the increase of fattening animals as determined at Rotham- 

 sted are uncertain. He, nevertheless, concluded that the 

 carbohydrates may serve as a source of fat to swine, and 

 under some circumstances to other animals also. 



It happens that Dr Armsby's book, founded to a great Prevailing 

 extent on Wolff's earlier editions, was the only work of the °£™%Z t 

 kind in the English language ; and hence, many of the rising young 

 generation of agricultural chemists, both in this country and chevmts - 

 in America, adopted the view that the albuminoids are the 

 main, if not the exclusive, source of the fat of our farm stock, 

 and of the butter of cows' milk. 



Under these circumstances it seemed desirable to consider 

 in some detail, both the experimental evidence bearing upon 

 the question, and the discussions which have taken place in 

 regard to it, during the last quarter of a century or more. 



1 Hermann's Handbuch d. Physiologic, Band 6, Theil 1, von C. v. Voit, 

 Leipzig, 1881. 



