Bamboo forest is now unused or used limitedly in Japan. We conducted the following five experiments to use bamboo as a main raw material for silage processing. Plant fractions of leaves and culms in two types of bamboos, Japanese timber bamboo (Phyllostachys bambusoides) and moso bamboo (P. pubescens) were examined for chemical composition of silage under three levels of moisture content of 35, 45 and 55% (Experiment 1), and under three levels of additives, sake lees (SL), lactic acid bacteria RO50 (RO50), and both SL and RO50 (Exp. 2). Silage fermentation quality in whole plant of moso bamboo was examined under three levels (5, 10 and 15%) of additives of SL and molasses (Exp. 3), and under addition of RO50, cellulase, molasses, and SL (Exp. 4), and chemical composition of bamboo silage in Exp. 3 and 4 were examined in Exp. 5. The results indicated that the silage quality did not change with moisture content; however, adding 5% SL significantly lowered pH and increased crude protein of silage, whose quality was evaluated as high because of low concentrations of butyric and propionic acids.

The economic loss of agricultural and forestry resources has overwhelmingly increased in recent decades due to feeding damage of sika deer (Cervus nippon), especially in western Japan. Utilization of a captured deer is becoming a critical problem concerning the prevention of wildlife damage. Using sika deer meat (hereafter called “deer meat”) for edible is not progressing because negative image such as hard and gamey flavor in Japan. Our previous study showed that eating quality of deer meat is improved by treatment with wakame. Also, this last report suggested that alginate contained in wakame may affect deer meat, because it has an ability to retain water. In this study, we examined the effects of treatment with wakame and sodium alginate on physical and chemical properties. Measuring items were as follows: drip loss, water holding capacity, cooking loss, shear force, free amino acid and related compounds content of deer meat. The water holding capacity significantly was higher in treatment with sodium alginate than additive free condition. The shear force value significantly was higher in treatment with wakame than additive free condition. These results suggested that treating with wakame lead to an improvement in the physical property of deer meat.

The aim of this study was to examine the effects of dietary sweet potato inclusion level on the growth performance and meat quality of growing-finishing Kagoshima Berkshire pigs. Twenty-eight Kagoshima Berkshire pigs (barrows) with an initial body weights of 60 kg were allocated to four diets in a completely randomized block design with seven pigs per diet. The diets included a corn-soybean basal diet (control, 0%) and three diets formulated by replacing the corn and soybean meal in the control diet with 10%, 20%, and 30% dried sweet potato. The diets had total digestible nutrients values of 70% and crude protein of 13.5%, and the pigs were reared under restricted-feeding conditions, being fed the diets at 80% of ad libitum. When each pig’s body weight reached 115 kg, the pigs were shipped, slaughtered and dissected, and five loin samples from each group were subjected to physical and chemical analyses and sensory evaluation. Daily weight gain decreased from 602 g for the control to 597 g, 565 g and 565 g for the 10%, 20%, and 30%, diets, respectively. As a result, the shipping age increased from 233 days for the 10% diet to 236 days for the control diet, 241 days for the 20% diet and 242 days for the 30% diets, respectively. However, the sweet potato inclusion level had no effects of the loin cross-sectional area and carcass characteristics. A comprehensive analysis of muscle tissue metabolites indicated that 19 substances significantly increased or decreased in response to the dietary treatment. Changes in metabolic pathways such as protein synthesis, glutamate metabolism, and the urea cycle were found. The tissue α-tocopherol concentration in the muscle tissue was markedly higher for the 30% group, whereas the α-tocopherol in the back fat adipose tissue did not differ between the diets. In the sensory evaluation, the meat from the 10% and 30% groups received higher evaluation scores for “preferred scent” and “rough taste of fat” than the meat from the control group. The meat from the 30% group received the highest evaluation scores for “ease of biting”, “ease of chewing”, and “pleasant taste”, respectively. These results demonstrate that the meat quality of Kagoshima Berkshire pigs can be controlled by adjusting the inclusion level of sweet potatoes in the growing-finishing diet.

This study was carried out to clarify the efficiency of applied nitrogen fertilizer using ¹⁵N-labelled fertilizer (¹⁵N) on rotational grazing pastures of giant stargrass (GS) and Transvala digitgrass (TR) in subtropical Okinawa, Japan. Dry matter yield, total nitrogen content and ¹⁵N recovery rate of the available herbages to be grazed were not significantly different between GS and TR pastures. The efficiency of nitrogen fertilizer on the available herbages was observed at 33.8 and 31.8% in GS and TR pastures, respectively. The fertilized ¹⁵N in the stubbles and roots, rhizosphere soils and available herbages averaged across the two grass pastures was recovered by 5.1, 10.7 and 32.8％, respectively. ¹⁵N recovery rate in the plant-soil system averaged across both GS and TR pastures was 48.5％, which means that 51.5％ of applied nitrogen fertilizer was lost from the soil-plant system in the present subtropical grazing pastures.

The objective of this study was to evaluate the utility of rubbed bamboo silage (RBS) as the roughage in fattening beef cattle. Eight Japanese Black steers (10 months old) were divided into two groups: one group was fed rice straw (Control Group) and the other was fed RBS (Experimental Group). Rearing methods except for provision of the roughage were the same in both groups. Both groups were fattened until they were 28 months old, followed by slaughter. The feed consumption of Experimental group decreased gradually after they were 18 months old. The time spent eating behavior by cattle of Experimental group was significantly smaller than that of Control group, when they were 11, 22 and 25 months old, and their rumination behavior was also smaller when they were 11, 13, 18 and 22 months old (P<0.05). Furthermore, the roughage value index (RVI) and ruminal pH of Experimental group were significantly lower than those of Control group, when they were 18 months old (P<0.05). The body weight of Experimental group decreased after they were 24 months old. Although the finishing body weight of Experimental group was 100kg lighter than that of Control group, the carcass traits were not different between the groups. Gross pathological changes in rumen inside wall were not observed in either group. There were also no differences in the length and density of ruminal papillae between groups. In conclusion, rubbed bamboo silage can serve as an alternative roughage source for fattening beef cattle, but longtime feeding (over 10 months) may give negative impacts on their growth and beef production.