Abstract
The changes of the nutritive value and dry matter yield of oat plant and silage with stage of maturity were investigated for the period of 60 days from June to August, 1975, in Hokkaido. Varieties used were Moiwa, Ohotsuku and Honami. The whole crop silage of oat was prepared at three different stages such as milk, dough and ripening stage, and their feed composition, chemical quality, and digestibilities were determined by the means of wethers. The results are summarized as follows. (1) Increase in the dry matter content was seen at the rate of 0.7% or 0.9% per day with an advanced stage of maturity from milk to ripening stage. The crude protein was contained more than 20% in the material at the vegitative growth stage, however, it decreased by two-third with maturity. The starch content of dough or ripening stage of oat ranged from 15% to 20%. (2) The dry matter digestibility of stover by the cellulase method (EDMD), it decreased as straight from vegitative growth stage to milk stage, and then it ceased to decreased from dough to ripening stages, and again it continued to decrease until overripening stage. (3) The TDN content of whole crop silage was not significantly different between milk, dough and ripening stages. However, the nutritive value of stover silage decreased with maturity. (4) The TDN of per 10a of Moiwa, Ohotsuku, Honami was 386kg, 394kg and 406kg, respectively. The amount of digestible starch per 10a was 147kg, 126kg and 97kg, respectively.
