i8o 
Journal of Agricultural Research 
Vol. XIV, No. 4 
per cent of crude fiber. To consider the changes broadly, it is evident 
that from the time the crop heads out until it is ripe no very marked 
alterations take place in the relative proportions of the various con¬ 
stituents of the dry matter present, and consequently Sudan grass does 
not materially deteriorate in feeding value on ripening. 
The hay used in the digestion trial was from a plot yielding 2.94 tons 
of field-cured hay per acre at one cutting. It was cut on August 5, 
1916, when in full bloom and was harvested in good condition. It was 
kept in the mow till used for the digestion trial in December, 1916. 
The animals used were two three-quarter blood Guernsey heifers about 
a year and a half old and averaging 600 pounds in live weight. These 
animals were of 75 per cent the same breeding, being sired by Rouge of 
Ames (24405), a son of Rouge IVs Son, while their dams were sired by 
Rouge IVs Son (18587). From birth until the start of the digestion 
trial these heifers received the same care and feed. Both were pregnant 
and in fair condition at the beginning of the experiment, and though 
No. 298 was rather larger than No. 301, they were a very uniform pair 
in all other ways. 
Table VII .—Description of animals used in trial 
Animal. 
1 
Age. 
Days bred. 
Weight. 
Heifer 298. 
Vr. mos. dys. 
I 617 
i 5 27 
63 
152 
Pounds. 
650 
550 
Heifer 301. 
Average.. 
167 
108 
600 
The digestion trial was run for a period of five days preceded by a 
preliminary period of seven days during which Sudan grass was fed as 
the only source of nutriment to the heifers. In the preliminary period 
it was found that 20 pounds per head per day of the hay would be a con¬ 
venient amount to feed; so this allowance was used throughout the 
experiment and the material left was weighed back daily. 
It has been found that the animals had no special need of being watered 
twice daily, so the watering was done at the beginning of each 24-hour 
period and the animals were weighed before and after watering. The 
attendant collected the feces with a scoop and deposited them in tarred 
galvanized-iron vessels which were provided with covers. 
A composite sample of the hay fed, and one of the orts were made at 
the end of the trial period. The feces from each heifer were mixed thor¬ 
oughly and sampled at the end of each 24-hour period, and these samples 
were air-dried. At the end of the trial an aliquot composite sample was 
made for the feces produced by each of the heifers during the 5-day trial 
period. 
