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The livestock industry is a major source of atmospheric volatile organic compounds (VOCs), but details on these emissions are not well documented in Japan. In particular, it remains unclear how the rearing method affects the emissions of VOCs from livestock, which originate primarily from feces and urine. Here we aimed to estimate the amounts of VOCs emitted from the feces and urine of tethered Holstein dairy cattle in a cattle shed in Japan. Dimethyl sulfide and acetone accounted for about 60% of the total VOCs emitted from feces, followed by formaldehyde and acetaldehyde. Also, dimethyl sulfide and acetone were the dominant VOCs emitted from urine, accounting for 90% of the total VOCs. The VOCs from manure were considered to be emitted between the excretion and removal of the manure during the cleaning of the shed. As a result of analyzing images from three cameras installed in the shed, the average time between excretion and cleaning during the daytime (8:00 am-5:00 pm) was 80 min for feces and urine, whereas at night (5:00 pm-7:00 am), the average time between excretion and cleaning was 480 min. Based on the above findings, the emissions of VOCs in the interval between excretion and cleaning of the shed were estimated. As a result, the emissions of VOCs from feces and urine per head of cattle in the shed were estimated to be 1.75 and 1.52 g day-1, respectively. Furthermore, contribution of VOCs emitted from manure to odor activity value (OAV) and hydroxyl radical reactivity (OHR) were also estimated. Volatile fatty acids and sulfur compounds emitted from feces estimated to have high contribution to OAV, whereas aldehydes contributed mainly for OHR from manure. [ABSTRACT FROM AUTHOR]

Volatile organic compounds (VOCs), CO2, temperature, and humidity in a private room in a care facility for the elderly were measured and the behavior of a resident and staff were recorded in order to clarify the effects of the resident's behavior, especially defecation, on indoor air quality. Average indoor concentrations of total VOCs (in μg m-3) in summer, autumn, and winter were 40.9, 16.7, and 18.8, respectively. Average indoor concentrations of CO2 in summer, autumn, and winter were 813, 761, and 1144 ppm, respectively, revealing a tendency for the concentrations of CO2 to be higher in winter, in contrast to the VOC concentration. The concentrations of VOCs and CO2 were 1.1 to 1.5 times higher when the resident was present in the room than when the resident was absent. This result suggests that one of the main sources of VOC and CO2 emissions in indoor air was the resident. Acetic acid, 1-butanol, propanoic acid, hexanoic acid, and phenol, which are contained in human sweat, exhaled air, and excrement, were the predominant VOCs in the air of the room regardless of the season, and these five components accounted for more than 90% of the total VOCs. The concentrations of these components were higher when the resident was present in the room, suggesting that the resident was the main source of these components. Based on the changes in the VOC and CO2 concentrations over time and the records of the resident and the staff, it was noted that VOC concentrations decreased, in some cases, before and after diaper changes. Our research suggests that certain aspects of the behavior of residents can be inferred by monitoring changes in indoor air quality. [ABSTRACT FROM AUTHOR]

We examined the antimicrobial susceptibility of 848 Escherichia coli isolates from 237 feces samples of wild sika deer (Cervus nippon) captured between 2016 and 2019 in 39 of the 47 prefectures of Japan. Five of the 237 wild sika deer (2.1%) carried E. coli with resistance to at least one antimicrobial, and all the resistant isolates showed resistance to tetracycline. The resistant isolates contained antimicrobial resistance genes that were similar to those in E. coli derived from humans and farm animals. Although wild sika deer are not currently likely to be a source for the transmission of antimicrobial resistance in Japan, they can potentially mediate antimicrobial resistance spread by coming into contact with humans, animals, and their surroundings. [ABSTRACT FROM AUTHOR]

To clarify the emissions of volatile organic compounds (VOCs) from hen rearing in Japan, we collected air samples from inside a hen shed for the four seasons in 2019 and analyzed 34 VOCs in the air samples by gas chromatography-mass spectrometry and high performance liquid chromatography. The temperature and humidity inside and outside of the shed were monitored simultaneously during each sampling campaign. The average concentrations of VOCs in the shed ranged from 150 to 427 µg m-3, the concentrations being higher in summer and lower in winter. Acetone, dimethyl sulfide, 2-butanone, 2-pentanone, and acetic acid were dominant throughout all the seasons and these five compounds accounted for 70-89% of the total VOCs. The reactivity of each VOC with hydroxyl radical was also calculated and dimethyl sulfide was found to be the most reactive VOC, accounting for 84-94% of the total hydroxyl radical reactivity. The emission rate (ER) for the total VOCs (µg h-1 kg-1) was 602 in winter, 7,900 in spring, 46,500 in summer and 37,600 in autumn, respectively. Acetone, dimethyl sulfide, 2-butanone, 3-pentanone and acetic acid had higher ERs throughout all the seasons, and these five components accounted for 70-90% of the ERs for the total VOCs. The ERs of the VOCs increased exponentially in accord with temperature increases inside the shed, indicating that the ERs of the VOCs depended on the ambient temperature. The annual VOC emission from one hen and from the hen shed was calculated to be 405 g y-1 and 121 kg y-1, respectively. [ABSTRACT FROM AUTHOR]

Invasive alien tree species can exert severe impacts, especially in insular biodiversity hotspots, but have been inadequately studied. Knowledge of the life history and population trends of an invasive alien tree species is essential for appropriate ecosystem management. The invasive tree Bischofia javanica has overwhelmed native trees on Haha-jima Island in the Ogasawara Islands, Japan. We explored forest community dynamics 2 years after a typhoon damaged the Sekimon primary forests on Hahajima Island, and predicted the rate of population increase of B. javanica using a logistic model from forest dynamics data for 19 years. During the 2 years after the typhoon, only B. javanica increased in population size, whereas populations of native tree species decreased. Stem diameter growth of B. javanica was more rapid than that of other tree species, including native pioneer trees. Among the understory stems below canopy trees of other species, B. javanica grew most rapidly and B. javanica canopy trees decreased growth of the dominant native Ardisia sieboldii. These competitive advantages were indicated to be the main mechanism by which B. javanica replaces native trees. The logistic model predicted that B. javanica would reach 30% of the total basal area between 2017 (in the eastern plot adjacent to a former B. javanica plantation) and 2057 (in the western plot distant from the plantation site), which is a maximum percentage allowing to eradicate under the present guideline of the National Forest. The results suggest immediate removal of B. javanica is required to preserve native biodiversity in these forests. [ABSTRACT FROM AUTHOR]

To clarify the nature and characteristics of volatile organic compounds (VOCs) emitted from dairy cattle within a cattle shed located in Chiba, Japan, air samples were collected and analyzed for the four seasons in 2017-2018. Thirty-four VOCs were determined by gas chromatography-mass spectrometry and high performance liquid chromatography. In addition, air temperature and relative humidity inside and outside of the shed were monitored during each sampling campaign to estimate the ventilation rate of the shed. The average concentrations of total VOCs (μg m-3) in the shed in each season were 50.5 (spring), 128.4 (summer), 168.8 (autumn), and 199.5 (winter). Ketones were always the most dominant components followed by alcohols and volatile fatty acids (VFAs). The sum of ketones, alcohols, and VFAs accounted for more than 80% of the total VOCs in all seasons. Acetone, 3-pentanone, 1-butanol, and acetic acid were the major components regardless of the season, accounting for more than 60% of the total VOCs. The average emission rates of total VOCs from the shed (μg h-1 kg-1) were calculated to be 623 (spring), 1520 (summer), 585 (autumn) and 469 (winter). The emission rates of almost all the VOCs except alcohols increased exponentially with increase of air temperature in the shed. The ranges of the emission rates for each class of chemical (μg h-1 k-1) were 39-170 (VFAs), 247-913 (ketones), 65-134 (alcohols), 40-122 (phenols), 10-122 (aldehydes), 4.17- 22.3 (sulfur compounds), and 0.0067-0.74 (indoles). Furthermore, the annual emissions of VOCs for a single dairy cattle and for the cattle shed were estimated to be 5.5 kg and 44 kg, respectively. [ABSTRACT FROM AUTHOR]

Strangles is a commonly diagnosed and important infectious disease of equids worldwide, caused by Streptococcus equi subsp. equi. We determined the SeM genotypes of S. equi isolated from imported horses at the Japanese border within the past 8 years, which allowed us to classify 12 strains isolated from these horses from each exporter into four allelic groups. These alleles were different from the alleles of past isolates found in Japan. Furthermore, four strains classified into the same allele were isolated from horses from one exporter over several years. In this study, S. equi isolates from different exporters had different SeM alleles. Attention to the hygiene status of farms will be necessary to prevent the incursion of strangles. [ABSTRACT FROM AUTHOR]