2:58 MAKUAL OF OATTLE-FEEDIJvra. 



sary for wliaterer formation of new tissue or of milk may 

 take place ; all the rest is excreted in the dung. On the 

 other hand, the urine of the ruminants is, like that of the 

 earnivora, very rich in phosphoric acid (20 to 45 per cent, 

 of the ash) when the animals are fed exclusively on milk, 

 or when full-grown animals are deprived of food for 

 several days, so that they finally subsist upon their own 

 flesh and fat When calves and lambs are fed large quan- 

 tities of grain, a greater or less quantity of pliosphoric acid 

 always appears in the urine. 



The method of excretion of the phosphoric acid of the 

 fodder therefore varies with the kind of feeding. Accord- 

 ing to Liebig, phosphoric acid is absent from the mine of 

 Ixerbivora because this liquid is usually alkaline and be- 

 cause the fodder usually contains much lime. Phosphate 

 of lime is insoluble in alkaline fluids, and therefore phos- 

 phoric acid only appears in the urine when more is con- 

 tained in the fodder than is sufficient to unite with the 

 lime. Presence of magnesia, on the other hand, as Bert- 

 ram ^ has recently shown, does not hinder the appearance 

 of phosphoric acid in the urine, even though the latter be 

 alkaline. When this takes place the urine is found to bo 

 free from lime. 



Other Ash IngreMentB^ — Of the alkalies of the fodder 

 95 to 97 per cent., of the magnesia 20 to 30 per cent., of 

 the lime only 2 to 6 per cent, and sometimes none, and of 

 the sulphuric acid and chlorine, nearly the whole quantity, 

 is excreted in the urine. The remaintier of the above- 

 named ash ingredients, so far as they are not held back and 

 used in the body or hi the production of milk, is foxmd, 

 along with the wliole of the silica, in the dung. 



* Biedermann's Central Blatfc, Jahrg 8, p. 108. 



