The objectives of the present study were to assess the feeding effect of silage of the extremely late-maturing guineagrass cultivar ‘Umaku’, in comparison with Sudangrass silage, on dry matter (DM) intake, nutrient sufficiency rate, intake and rumination activity, and ruminal fermentation in Japanese Black cows. A feeding trial was carried out with Sudangrass silage or guineagrass silage ad libitum using a crossover design. The DM intake of guineagrass silage by the cows was higher than that of Sudangrass silage. The sufficiency rates of crude protein and total digestible nutrients for the maintenance period of Japanese Black breeding cows exceeded 100％ in the animals fed the guineagrass silage. Guineagrass is likely to be easy to digest into small pieces, because rumination time per 1 kg of DM and fiber (NDFom and ADFom) intake in the guineagrass-fed animals were shorter than those in the Sudangrass-fed animals. The guineagrass-fed animals had higher acetic acid concentrations in their ruminal fluid due to their higher DM intake than the Sudangrass-fed animals. These findings indicate that the guineagrass cultivar ‘Umaku’ is suitable for feeding ad libitum as roughage during the maintenance period of Japanese Black breeding cows.

Although numerous reports on the surveys conducted on public pastures exist, none of them provide detailed information on the work contents and working hours on public pastures. In this study, we investigated the work content and working hours of grazing monitoring, which is one of the important tasks on public pastures. We also examined the labor-saving effects of ICT on grazing monitoring and the possibility of increasing the number of breeding cattle. The results revealed that the work and time required for grazing monitoring varies among public pastures. It also became clear that grazing monitoring requires a great deal of time and effort. Attempts are also being made to utilize ICT technology to save labor in grazing monitoring. However, the results of the break-even point analysis suggest that the introduction of ICT technology in grazing monitoring may not lead to labor savings and an associated increase in the number of breeding cattle, depending on the management situation of public pastures.

This study aims to establish a method for estimating the composition of raw materials of eco-feed used in Okinawa prefecture, using near-infrared spectroscopy. We have developed and evaluated a calibration model and examined its practical feasibility. Herein, 100 samples were collected for calibration modeling and 20 for calibration model evaluation. Calibration models were constructed for evaluating general composition, gross energy (GE), and enzymatic digestibility of organic matter (EDOM) through multiple linear regression analysis (MLR) and partial least squares method (PLSR). The coefficients of determination (R²v) and standard deviations of the estimation error (SDP) for CP, EE, NFE and GE were 0.92 and 4.75, 0.90 and 3.52, 0.90 and 3.11, 0.86 and 0.27, respectively, through MLR. And R²v and SDP through PLSR were CP (0.96 and 3.15), EE (0.87 and 4.10), NFE (0.95 and 4.24), GE (0.86 and 0.27), respectively. For CP, EE, NFE and GE, the practical accuracy was evaluated very high or high. But for CA, CF and EDOM, there were no practical calibration models obtained through neither MLR nor PLSR.

This study examined body temperature fluctuations in Japanese Black calves using a progester one-free Controlled Internal Drug Release (blank CIDR) for sheep with a small data-logger. This experiment was conducted over two seasons, pasture season (May and August) and non-pasture season (November and January). A total of 18 female calves (2 - 8 months old) were evaluated, for 9 of those calves, the CIDR was retained within the vagina. Detailed calf body-temperature fluctuations were recorded using a CIDR and data-logger restricted to female calves under five months and 100 kg body weight. During both seasons, the minimum body temperature was reached during the early morning, whereas the maximum body temperature was attained in the afternoon. There were no significant differences in afternoon to nighttime body temperatures between the pasture and non-pasture season.