FEEDING OF ANIMALS. 331 



quantity of beans compared with that in the barley by oil, in 

 the proportion of 1 part of oil for 2£ parts of starch. 



With a view to the careful collection, sampling, and analysis, 

 of the excrements, the sheep were kept under cover, on rafters, 

 through which (but with some loss) the solid and liquid ex- 

 creta passed on to a sheet-zinc flooring, at such an incline 

 that the liquid drained off at once into carboys containing 

 oxalic acid ; and the solid matter was removed two or three 

 times daily, and also mixed with oxalic acid. 



After a preliminary period of eight weeks the exact feeding 

 experiment was continued for thirty-two weeks more — from 

 January 25 to September 6. Commencing on March 26, and 

 ending on August 9, samples of the excrements were taken at 

 intervals, in each case for several consecutive days — namely, 

 4, 5, 5, 7, 7, 7, 7, 7, 7, and 7 days ; and the results here given 

 are the means of the seven 7-day periods. The amounts of Nitrogen 

 nitrogen so indicated to be not recovered in either the increase ^^^ 

 or in the excreted matters were, in the four pens, respectively for. 

 12.5, 25.4, 15.2, and 17.7 per cent of the nitrogen supplied in 

 the food. It is to be observed that the estimated loss is the 

 greatest with the most, and the least with the least, nitrogen 

 in the food. The question arises — Whether the greater esti- 

 mated loss is connected with an under-estimate of the nitro- 

 gen in the increase of the animals feeding on the more highly 

 nitrogenous food, or with an actually greater loss from de- 

 composition in the case of the more highly nitrogenous 

 excrements. 



In 1858, Henneberg 1 made experiments with two oxen, Henne- 

 each separately. The animals were kept on sustenance food h& ^^ 8 

 only. After a preliminary period of several weeks, there 

 were three periods of more exact experiment — the first from 

 February 27 to March 27, the second from March 28 to May 

 21, and the third from May 22 to July 15 ; and during three 

 days towards the end of each of these periods the excrements 

 were collected and analysed. Ox No. 1 gained 6 lb. during 

 the three days of the first period, 1 lb. during those of the 

 second, and 11 lb. during those of the third. The percentage Nitrogen 

 of the nitrogen of the food which was not recovered in the ^^^ 

 excrements was, for the respective three-day periods, 5.7, 28.8, for. 

 and 15.1, or an average of 16.5. Ox No. 2 neither gained nor 

 lost during the first three-day period, lost 3 lb. during the 

 second, and 8 lb. during the third ; and the analyses of the 

 excrements showed a gain of nitrogen compared with that in 

 the food of 9.6 per cent over the first three days, a loss of 

 24.7 per cent over the second three, and a gain of 6.3 per cent 



1 Beitrdge zur Begriindung einer rationellen Futterung der Wiederkditer, 

 Heft 1, 1860. 



