ANIMAL HUSBANDRY. IO3 



this knowledge it is not possible to settle the question of the rela- 

 tive economy of hay and silage production. In the experiments 

 the comparative digestibilities of green oats and tares, oat and tare 

 hay, and oat and tare silage are being investigated. The trial 

 is carried out in duplicate with sheep, two wethers being used for 

 the purpose . The period of trial is three weeks, but the final 

 figures are based on the results obtained in the last fortnight, 

 during which the conditions of experiment are considered to be 

 stable. The sheep are kept during the experiment in specially 

 designed feeding stalls, and harnessed with an equipment con- 

 sisting essentially of a rubbered canvas sheet fixed by suitable 

 means to the hindquarters of the sheep. The solid excreta fall 

 down a funnel-shaped shoot attached to the cage into a receptacle 

 below. The urine drains through the perforated floor and is 

 caught in a bottle. The sheep are weighed at the beginning and 

 end of each period, and full analyses made of the feeding stuffs 

 suppHed and of the dung and urine. From these data, and know- 

 ing the weight of the foods, the proportion actually digested can 

 be ascertained by subtracting from the known constituents of 

 the food consumed, the known constituents voided in the dung. 



Feeding Value of Oat Straw. 

 At this point we may leave for a moment the work in progress 

 at Aberdeen and Cambridge, and refer briefly to an investigation 

 of the feeding value of oat straw which is being carried out by the 

 Advisory Chemist at Armstrong College, Newcastle-on-Tyne. 

 This enquiry arose from a consideration of the fact that oat straw 

 apparently varies very much in quality, inasmuch as farmers in 

 many districts feed cattle during the winter almost entirely on 

 roots and straw, whereas in other districts this system of feeding 

 is not satisfactory. An exhaustive chemical examination of 

 swedes obtained from various districts showed that roots grown 

 in districts which made little success in feeding roots and straw 

 were just as good as those from districts where this system of 

 feeding was successful. The difference, therefore, apparently 

 lay in the straw. The straw investigation has now proceeded 

 for some eighteen months, and the considerable initial difficulties 

 in connection with the analytical methods have been overcome. 

 The preliminary work has shown that the chief variations in 

 composition are due to the sugar and albuminoid contents of the 

 straw, and principally to the sugar. The important cause of 

 variation is the district where the crop is grown, straws from 

 northern counties having a total sugar content about three times 

 as great as those obtained from other districts. Further, oat 

 straw from the western side of the northern counties is much 



