Effects of fermentative quality of corn silage on lactation, blood metabolites, and rumen fermentation in dairy cows.

We investigated the effect of fermentation quality of corn silage on dry matter intake (DMI), milk yield, ruminal fermentation, methane (CH4 ) emissions, and plasma metabolites in lactating cows. Six lactating Holstein cows were used in a 2 × 2 crossover design with two dietary treatments containing high quality corn silage with lower pH (high group) or low quality corn silage with higher pH (low group). The cows were fed partial mixed ration (PMR containing 50%DM of each corn silage) ad libitum plus 0.7 kg/day of concentrates at milking. The DMI of cows in the low group (24.8 kg/day) tended to be lower (p < 0.10) than that in the high group (26.8 kg/day). The dietary treatment did not affect milk yield or milk fat, protein, or lactose concentrations. The ruminal acetic acid proportion of the low group was significantly higher (p < 0.05) than that of the high group. The CH4 emission per DMI of the low group tended to be higher (p < 0.10) than that of the high group. The plasma concentration of the total cholesterol (TCHO) and the activity of aspartate aminotransferase and alanine aminotransferase of the low group were significantly higher than those of the high group.

Measurement of Volatile Fatty Acids in Silage through Odors with Nanomechanical Sensors.

The measurement of volatile fatty acids (VFAs) is of great importance in the fields of food and agriculture. There are various methods to measure VFAs, but most methods require specific equipment, making on-site measurements difficult. In this work, we demonstrate the measurements of VFAs in a model sample, silage, through its vapor using an array of nanomechanical sensors-Membrane-type Surface stress Sensors (MSS). Focusing on relatively slow desorption behaviors of VFAs predicted with the sorption kinetics of nanomechanical sensing and the dissociation nature of VFAs, the VFAs can be efficiently measured by using features extracted from the decay curves of the sensing response, resulting in sufficient discrimination of the silage samples. Since the present sensing system does not require expensive, bulky setup and pre-treatment of samples, it has a great potential for practical applications including on-site measurements.

Recovery and utilization of compost heat from an enclosed vertical-type composting facility development of warmed water supply system using compost heat.

This paper describes a compost heat utilization system that recovers the exhaust heat generated by an enclosed vertical-type composting facility (EVCF) installed in a dairy farm with 150 heads of dairy cows. The recovered exhaust heat warms the water supplied to dairy cows. This study determines the temperature of the supplied water and the heat utilization efficiency of the system. During operation, the EVCF generated a compost temperature of 60-70°C and an exhaust temperature of 60°C. The system provided warm (30°C) water throughout the day by raising the water temperature at night when the drinking water requirements were reduced and heat demand used for warming the water was low. Thermal energy generated 356% of the power consumption, and 49.3% of the generated energy was used for warming the water. The compost heat used to warm water was 2017 MJ d-1 , which was equivalent to 68.7 L d-1 of kerosene when the same amount of water was warmed in a boiler.