暖地栽培ビート副産物の飼料価値に関する研究 (第1報) ビートトップの成分と飼料価値

The cultivation of the sugar beet in warm regions has been encouraged for the purpose of decreasing importation of sugar and of utilizing by-products of the sugar beet cultivation to live-stock feeding. With a view to making clear the chemical composition and the feeding value of by-products of the sugar beet cultivated in warm regions, some experiments have been made. The results obtained are summarized as follows : (1) No distinct variation in chemical composition of sugar beet tops could be found between the various varieties, nor between beet tops harvested at different times. Crude protein content of blades was over 20 per cent. (2) Oxalic acid contents in various parts of sugar beets were determined. (cf. Table 4). Beet tops contained 0.25-0.51 per cent. oxalic acid. In beet tops of such varieties as KL-E. Verna and Polish content of oxalic acid was comparatively high, but in those of KL-AA and Cesena rather low. (cf. Table 5). (3) Carotene content was 2.9 mg./100 g. in beet tops in the bolting Period and 2.7 mg./100 g. in beet top silage. (4) The results of digestion experiments on rabbits using beet tops (with dry matter content 12. 2 percent.) showed that the digestibility of organic matter was 91.7 per cent ; the digestible crude protein was 1.64 per cent. and the total digestible nutrient 9.5 per cent. (cf. Tables 6 and 7). (5) The beet top silage made without any additive had a satisfactory pH 4.09, and contained 2.65 per cent. lactic acid, 0.47 per cent. acetic acid, and 0 per cent. butyric acid. The rate of ammoniacal nitrogen to the total nitrogen was 5 per cent. The silage seemed to be palatable to live-stock. (6) Oxalic acid content of the beet top silage was 0.43 per cent. It was found that about thirty percent of oxalic acid diminished during storage. (7) The results of digestion experiments with the beet top silage on rabbits are shown in Table 12. Contents of dry matter, digestible crude protein and the total digestible nutrient of the silage were 13.5, 1.5 and 9.6 per cent. respectively. (8) The loss of dry matter during storage was 27 per cent. Besides, the loss of nutrients in oozed juice was also studied. (cf. Table 16).