Studies on Silage-Making. V. : On the Effects of Sodium Metabisulfite as a Preservative and of the Rate of Mixing Soybean with Corn.

The author has already published a report on the effects of starch feed, urea, and AIV acid on silage-making. In this paper the results of small scale experiments carried out on the effect of sodium metabisulfite (Na2 S2 O5) as a preservative and also on the effect of the proportion in mixing green soybeans in green maize will be reported. (1) Chopped sweet potato vines were ensiled according to the following methods ; a) with the addition of sodium metabisulfite at the rate of 0.5 per cent.; b) with the addition of molasses mixed feed at the rate of 10 per cent. and c) without any addition of the preservative. The results of comparison of quality, characteristics and chemical composition: of the experimental silages are shown in tables 2, 3, and 4. The bisulfite treated silage had good quality and was charactiristic of greenish color, and was free of undesirable and unpleasant odors. (2) Chopped sweet potato vines were preserved with the addition of sodium metabisulfite at the rate of 0.4 per cent. The resulting silage had lactic acid 1.04, acetic acid 0.23 per cent., PH 4.41 and no butyric acid after the storage for 172 days. The results 6f digestion trials on rabbits are shown in table 9. Digestible crude protein and total digestible nutrients were respectively 6.0 and 48.7 per cent on the dry matter basis. (3) Corn, green soybeans and mixtures of corn and soybeans were ensiled according to the ratio as shown in table 11. Investigations on organic acids, the pH value, and chemical composition of the silages were made. When corn alone or a 7 : 3 mixture of corn and green soybeans was ensiled, the resulting silage had a very good quality. , These data suggest that mixing green soybeans in corn to an amount of 30 to 40 per cent of corn does not lower the quality of the resulting silage