暖地栽培ビート副産物の飼料価値に関する研究 (第2報)ビートトップサイレージ,乾燥ビートトップおよびビートパルプの飼料価値

The authors have already published a report on the feeding values of by-products of sugar beet cultivation in warm regions. This is the report of some experiments successively made on the feeding values of beet top silage, sun-cured beet tops, beet pulp silage and beet pulp. The results obtained are summarized as follows: 1)The beet top silage made without any additive had a good value of pH 3.7, and contained 3.6 per cent lactic acid and 0 per cent butyric acid. Pro-vitamin A content of the beet top silage was 1-2 mg. per 100 g. The silage was found to be a favourite feed with live-stock. Beet top silage contained 544 mg. oxalic acid per 100 g. The nutrient loss in fermentation process was 24 per cent in organic matter and 9 per cent in crude protein. The results of digestion experimets on rabbits showed that the digestibility coefficient of organic matter was 78 per cent; the digestible crude protein was 2 per cent and the total digestible nutrient 10.4 per cent(cf. Table 9). 2)The beet tops lost 24 per cent of organic matter, 17 per cent of crude protein and 86 per cent of carotene during 10 days of sun-curing. The results of digestion experiments on rabbits showed that the digestibility coefficient of organic matter was 66 per cent, lower than that of fresh beet tops or beet top silage. The sun-cured beet tops were less palatable to rabbits than the fresh beet tops or the beet top silage. The contents of digestible crude protein and total digestible nutrient were 8.4 per cent and 42.0 per cent respectively. 3)A good silage was able to be prepared from beet pulp. Furthermore, addition of morea in silage-making with the beet pulp was effective and the morea added silage was palatable to live-stock; it had the following properties: pH 4.15, lactic acid 1.89 per cent. acetic acid 0.25 per cent and butyric acid 0 per cent. The results of digestion trials on goats are shown in Table 19. The digestible crude protein and the total digestible nutrient were respectively 1.8 per cent and 13.5 per cent. 4)The digestible crude protein and the total digestible nutrient of dried beet pulp were respectively 5.9 per cent and 69.0 per cent. 5)The rsults of digestion trials by chromic oxide method using goats as experimental animals were compared with those obtained by the total collection method(cf. Table 23). The application of chromic oxide method to estimating the digestibility seems to be practically satisfactory and convenient.