FEEDING OF ANIMALS. 269 



pigs, re-calculated, making correction, as far as practicable, Re-caicu- 

 for the amounts of the constituents in the different foods If^ddnTto 

 which are assumed to be indigestible, or otherwise not of Wolff's 

 food- value, according to the tables given by Emil von Wolff tables - 

 in the edition of his work published in 1888. He there gives 

 for nearly 200 different articles of stock foods — the percent- 

 ages of water, mineral matter (ash), crude protein, crude fibre, 

 non-nitrogenous extractive matters, and crude fat ; and then 

 the percentages of digestible albuminoids, digestible carbo- 

 hydrates, and digestible fat. In applying his data to our 

 results, the amount of the crude substance in each description 

 of food is reduced in the proportion which his figures show of 

 crude to digestible in the same description of food. Further, 

 in the case of the so estimated amounts of digestible fatty 

 matter, the figure obtained has been multiplied by 2.4 to 

 bring it approximately to its equivalent of carbohydrate, the 

 amount then being added to the other digestible non-nitro- 

 genous substance, so reckoning the whole as carbohydrate. 

 Lastly, as Wolff makes no correction for the non-albuminoid 

 condition of a large portion of the nitrogen in succulent roots, 

 it has been assumed, in accordance with results obtained at 

 Eothamsted and elsewhere, that in Swedish turnips only 45 

 per cent, and in mangels only 40 per cent, of the total nitro- 

 gen will exist as albuminoids. 



There are obvious objections to some of the modes adopted 

 for the determination of the digestible constituents of the 

 various foods, which render them inapplicable without con- 

 siderable reservation, to the estimate of the amounts of the 

 constituents which will probably be actually digested in the 

 case of ordinary liberal rations. But, if accepted as approxi- 

 mations only, they undoubtedly afford useful data for some 

 general conclusions. 



Neither space nor time will permit of either the record or Re-calcu- 

 the discussion of the re-calculated tables. It must suffice j-JJJSJf ' 1 " 

 here to say that the results as so re-calculated, that is making former 

 correction as far as present knowledge permits, for the prob- °P in%ons - 

 able amounts of the indigestible or non-available constituents 

 of the various foods, not only fully confirm the conclusions 

 drawn on a careful study of the circumstances of the experi- 

 ments, and of their results, more than forty years ago, but 

 they bring out the points then maintained still more clearly 

 to view. 



The Experiments with Pigs. 



Let us next see whether experiments with pigs lead to Feeding ex- 

 similar conclusions. The pig requires much less bulk in his p ^^ e ^i s s 

 food than the ruminant. His food, and especially his fatten- 



