Solid-liquid separation solids from anaerobically digested dairy cow slurry (hereinafter, separated solids) are used as bedding material, but there are hygienic concerns that such material, being derived from manure, may cause outbreaks of mastitis. In this study, we investigated the hygienic status of separated solids during bedding material preparation and during use as bedding at a dairy farm, using Escherichia coli counts as an indicator. Two days’ worth of separated solids were deposited in a pile. Then, every 2 days, 4 times in total, a new pile of separated solids was redeposited after each existing pile was turned and moved. This resulted in 4 piles, and the fourth pile was then used as bedding. Due to turning, the temperature of the separated solids fl uctuated between 45 °C and 80 °C in the summer and between 40 °C and 70 °C in the winter; throughout the year, the separated solids had experienced temperatures of 55 °C or greater for a total of 100 h by the time of the fourth turning. The E. coli counts in the separated solids immediately after solid-liquid separation were 102 to 103 CFU/g-wet but declined to below the limit of detection in 90 % of the samples prior to placement in stalls. These results indicate that aerobic fermentation of separated solids is effective in eliminating E. coli. 　　Counts of E. coli in the bedding were below the limit of detection prior to placement in stalls, and then increased rapidly to between 10² and 10⁴ CFU/g-wet within 2–3 h after placement, reaching 10⁴ to 10⁵ CFU/g-wet by 22–23 h after placement. In addition, E. coli counts in unused bedding that remained in front of the brisket locator since the start of the investigation increased to 10³ to 10⁴ CFU/g-wet at about 12 h after placement in the stalls. These results did not indicate an inhibitory effect of the separated solids bedding after short-term fermentation on the growth of E. coli. 　　The relation between average barn temperature and average E. coli counts in the bedding during use prior to the placement of new bedding in stalls had a high positive correlation (r = 0.918) in the range of 1.6 °C to 23.7 °C. At temperatures of 22.7 °C or higher, E. coli counts reached a level estimated to be conducive to the outbreak of mastitis (10⁶ CFU/g-wet or greater). 　　The separated solids bedding was found to have the following characteristics. (1) Moisture at the time of placement in stalls was high, at about 78 %, and because of this, (2) E. coli counts tended to be low when moisture was high; (3) moisture was high and E. coli counts were low when the barn temperature was low; and (4) moisture was low and E. coli counts tended to be high when the barn temperature was high.

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The objective of this study was to investigate the ability of an ammonia (NH₃)-recovery device to recover NH₃ over a full year from a closed vertical composting facility (CVCF), and the possibility of using the recovered ammonium solution as fertilizer. A 600-L NH₃-recovery device fi lled with phosphoric acid solution was connected to a CVCF belonging to a pig farmer in Fukushima (S Farm, 200 head of mother pigs). There were four periods of 10-day experiments: November 2017 and January, April and July 2018. The concentration of NH₃ of exhaust changed from 1833–3222 ppm at the device inlet to 117–149 ppm at the outlet, and average NH₃ removal rate was 94.7 %. The recovery solution contained 6.06–6.60 % of nitrogen and 18.6–20.5 % of phosphoric acid. Inclusion of 150 kg of phosphoric acid was suffi cient to capture about 30 kg of nitrogen in one batch. The mass of solution increase that consisted of recovered nitrogen and water from dew condensation was relatively small in summer, suggesting the possibility of obtaining high ammonium phosphate concentrations depending on conditions. In addition, no harmful components according to the Fertilizer Regulation Act were detected, and the recovered ammonium solution had the same effect as the control fertilizer on seedling growth. Thus, the recovered ammonium solution can be used alone or as raw material for mixed compost compound-fertilizer.

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Typhoon 1821 “Jebi” hit central Japan on September 4th, 2018, caused damages more than 20 billion yen on greenhouses. We surveyed pipe-framed greenhouses damaged by the Typhoon in Kyoto and Gifu prefecture to elucidate behaviors of damaged pipe-framed greenhouses in fl at and mesomountainous areas. For wind pressure, the damage causes of pipe-framed greenhouse were positive pressure on windward side, negative pressure by separated fl ow, positive pressure by re-attachment fl ow, the change of inner pressure, lee eddy on mesomountainous area, convergence effect by topographic feature and structures around greenhouse, and tornado. For the structure of pipeframed greenhouse, loss of bearing power of soil, lack of bracing, partial loss of area of arch pipe, and destruction of connecting material made by plastics caused collapse of pipe-framed greenhouse. Further, impacts of typhoon-generated missiles were occurred by strong wind.

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