Abstract
This experiment was carried out to evaluate the feeding value of corn silages which were prepared from various varieties different in maturing detes, through digestion trials by wethers in 1974 to '77. Also, application of the Shintoku formula for estimating TDN by dry matter weight of silage materials were examined by comparing to the digested value by wethers. The results obtained were as follows: 1. In the case of early and medium maturing varieties, yields DM and TDN increased by 30-50%, when they were planted in high plant population with high level fertilization compared with those in standard plant population with standard fertilization. There was no difference in nutritive value between two silages which were produced from these two procedures. 2. Dry matter and TDN yields of early and medium varieties prepared by above-mentioned procedures were shown to be similar to those of late varieties. 3. Estimated TDN value of Shintoku formula was a little larger than that obtained by digestion trials. This overestimated value seemed to derive from that the Shintoku formula negrected DM losses of 5-10% during process of silage making and also there was an overestimation in nutritive value of stover in late maturing varieties.
