AGRICULTURAL EXPERIMENT STATION. 



27 



(2) The rubber bag and harness which are attached to the 

 animal during the time that it is necessary to collect the excre- 

 ments. 



The form of the stall or pen depends upon the kind of animal 

 used. The digestion trials made by this Station have been almost 

 entirely with sheep, and the pen shown in the accompanying plate 

 was devised here for use with this animal. The sides of these 

 pens are 3 V — 9 U high and are built of four inch spruce sheathing, 

 with spaces. 



As can be seen by reference to Plate III, the pens are so con- 

 structed that four sheep can be used at one time. As shown in 

 Fig. A, each pen has a floor space of twenty-two square feet. 



In Fig. B nearly all of one side of each pen has been swung 

 from the position a & to the position a c, forming a stall 18x48 

 inches in dimensions, in which the sheep can stand and lie at ease 

 but cannot turn around. 



It is well known to those familiar with the methods of digestion 

 experiments that a feeding period of from twelve to fourteen days 

 is necessary, at least the first seven days of which must be devoted 

 to a preliminary feeding before it is safe to collect the excrement. 

 During this first seven days the animal may have the liberty of the 

 pen as shown in Fig. A. When, however, the excrement bags 

 are attached it is necessary to confine the animals in the stalls as 

 shown in Fig. B, either during the entire five days or at least 

 while the contents of the bags are being removed. 



During the last five days, while confined in the smaller pens, the 

 animals stand upon a movable slat floor, the spaces between the 

 slats allowing the urine to flow out of the way so that neither the 

 animal nor the bags become soiled. The outer end of each of the 

 small pens contains an aperture through which the animal's head 

 has access to the feeding boxes which are attached outside. These 

 feeding boxes are wooden boxes-lined with zinc, which are extend- 

 ed upwards with galvanized iron to a height that entirely prevents 

 the scattering of the food outside. The rear end of the smaller 

 pens consists in part of a sliding panel, which allows the conven- 

 ient removal of the contents of the excrement bags. 



During the seven days that the dung is not collected the animals 

 are freely bedded with dry, clean sawdust. When the bags are 

 attached the bedding is removed and the floors thoroughly swept, 

 so that it is possible to see whether any loss of dung has occurred. 



