Manoalide derivatives from a marine sponge Luffariella sp. collected in Palau     

Michio  NAMIKOSHI  Shigeo  SUZUKI  Shiori  MEGURO  Hiroshi  NAGAI  Yoshio  KOIKE  Akira  KITAZAWA  Hisayoshi  KOBAYASHI  Taiko  ODA  Junko  YAMADA 《Fisheries Science》2004,70(1):152-158

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A note on the genetic diversity of the vulnerable aquatic macrophyte Sparganium erectum and its congeners (Sparganiaceae) in rural wetland in Japan     

TEMPEI ISHII  YUICHIRO NAKAYAMA  MIKIO KOBAYASHI  HIROFUMI YAMAGUCHI 《Weed Biology and Management》2004,4(4):230-234

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Search for regulatory factors of the pituitary-specific transcription factor PROP1 gene     

Naoto NISHIMURA  Hiroki UEHARU  Hiroto NISHIHARA  Shiori SHIBUYA  Saishu YOSHIDA  Masashi HIGUCHI  Naoko KANNO  Kotaro HORIGUCHI  Takako KATO  Yukio KATO 《The Journal of reproduction and development》2016,62(1):93-102

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Chronic low-dose exposure to imidacloprid potentiates high fat diet-mediated liver steatosis in C57BL/6J male mice     

Collins NIMAKO  Yoshinori IKENAKA  Yuko OKAMATSU-OGURA  Jussiaea V. BARIUAN  Atsushi KOBAYASHI  Ryo YAMAZAKI  Kumiko TAIRA  Nobuhiko HOSHI  Tetsushi HIRANO  Shouta M. M. NAKAYAMA  Mayumi ISHIZUKA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(3):487

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Identification of the core rumen bacterial taxa and their population dynamics during the fattening period in Japanese Black cattle     

Hiroto Miura  Takuya Hashimoto  Yukiko Kawanishi  Hiroki Kawauchi  Ryo Inoue  Noriaki Shoji  Kunihiko Saito  Mario Sekiya  Yosuke Saito  Jumpei Yasuda  Chiemi Yonezawa  Tetsushiro Endo  Hirotaka Kasuya  Yutaka Suzuki  Yasuo Kobayashi  Satoshi Koike 《Animal Science Journal》2021,92(1):e13601

The rumen microbiota comprises a vast range of bacterial taxa, which may affect the production of high-quality meat in Japanese Black cattle. The aim of this study was to identify core rumen microbiota in rumen fluid samples collected from 74 Japanese Black cattle raised under different dietary conditions using 16S rRNA gene amplicon sequencing. In the rumen of fattening Japanese Black cattle, 10 bacterial taxa, showing >1% average relative abundance and >95% prevalence, irrespective of the dietary conditions and the fattening periods, were identified as the core rumen bacterial taxa, which accounted for approximately 80% of the rumen microbiota in Japanese Black cattle. Additionally, population dynamics of the core rumen bacterial taxa revealed two distinct patterns: Prevotella spp. and unclassified Bacteroidales decreased in the mid-fattening period, whereas unclassified Clostridiales, unclassified Ruminococcaceae, Ruminococcus spp., and unclassified Christensenellaceae increased during the same period. Therefore, the present study reports the wide distribution of the core rumen bacterial taxa in Japanese Black cattle, and the complementary nature of the population dynamics of these core taxa, which may ensure stable rumen fermentation during the fattening period.  相似文献   

Seasonal changes in semen characteristics, composition of seminal plasma and frequency of acrosome reaction induced by calcium and calcium ionophore A23187 in Large White boars     

Murase T  Imaeda N  Yamada H  Miyazawa K 《The Journal of reproduction and development》2007,53(4):853-865

This study attempted to explain the mechanisms regulating boar fertility by examining seasonal changes in semen characteristics, the composition of seminal plasma and responsiveness of sperm acrosomes to Ca(2+) and the Ca(2+) ionophore A23187 (Ca(2+)/A23187). Sperm-rich and sperm-poor fractions were separately collected from 3 mature fertile Large White boars once a month over a one-year period. During the period of study, ambient temperature and relative humidity were recorded for within the stall in which the boars were kept and the semen characteristics, composition of the seminal plasma of sperm-rich fractions, and occurrence of the acrosome reaction in response to Ca(2+) (3 mM)/A23187 (0.3 microM) were examined. The highest mean maximum and minimum ambient temperatures were recorded in August-September, whereas the lowest mean maximum and minimum ambient temperatures were recorded in December and January, respectively. There was a moderate peak in relative humidity from July to October. The lowest percentages of motile spermatozoa and of spermatozoa with intact acrosomes and highest percentage of spermatozoa with abnormal morphology and strongest agglutination were seen in August-September. The total protein and albumin concentrations were lowest in August-September. Testosterone levels increased gradually as day length decreased after the summer solstice (June) and peaked in October-November. The percentage of acrosome reactions in response to Ca(2+)/A23187 was highest with the quickest response in August-September, as shown by the shortest time required for 50% of relative acrosome reactions. The farrowing rates were lowest in these same 2 months. These results suggest that seasonal infertility in Large White boars may be due, at least in part, to a combination of low motility, abnormal morphology including acrosomal abnormality, and early occurrence of the acrosome reaction in response to stimulus, possibly resulting from a decrease in acrosomal stabilizing proteins in the seminal plasma during summer. These changes may be modulated by heat/humidity stress and/or photoperiod-regulated testosterone.  相似文献   

Effects of tris(1,3-dichloro-2-propyl) phosphate on epididymal sperm parameters in adult male rats     

Shohei KOBAYASHI  Natsuko KAWANO  Kenji MIYADO  Ryo OHTA  Takahiro AKIMOTO  Taichi HATAKEYAMA  Maiko KAWAGUCHI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(1):153

Tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) is widely used as a flame retardant and is known to exhibit anti-androgenic effects in vitro and in vivo. To assess the reproductive toxicity potency of TDCIPP, we investigated the effects of 7 days of TDCIPP oral administration on epididymal sperm motion and concentration in adult male Wistar–Imamichi rats. Thirty-five days after the final administration, sperm parameters were evaluated by computer-assisted sperm analysis. Results showed that sperm swimming progression and vigor and sperm concentration in TDCIPP-treated rats were unexpectedly higher than those in control rats. TDCIPP did not significantly affect the percentage of motile sperms or sperm swimming pattern. These results contribute to the understanding of the biological effects of TDCIPP.  相似文献   

Microbial biomass and activity along a natural pH gradient in forest soils in a karst region of the upper Yangtze River,China     

Ye Tian  Kikuo Haibara  Hiroto Toda  Fangjun Ding  Yanhui Liu  Dongsu Choi 《Journal of Forest Research》2008,13(4):205-214

Mountain closure, considered an effective and economic measure for natural restoration of degraded forest ecosystems, has been widely carried out in the karst region of southwest China. The aim of this study was to evaluate microbial aspects of soil quality after mountain closure by analyzing soil microbial biomass, basal respiration, metabolic quotient, and relationships with basic chemical properties in Guizhou Province, a karst region of the upper Yangtze River. Soil quality was considered poor from the low levels of microbial biomass carbon (MBC), nitrogen (MBN), and microbial quotient (MBC/total C and MBN/total N), but high metabolic quotient (qCO₂). Soil pH, showing marked variation from 4.1 to 7.9 in this karst region, was proved to significantly affect soil microbial biomass and activity. Soil microbial biomass, microbial quotient, and soil basal respiration declined significantly with decreasing soil pH, while qCO₂ showed an apparently increasing, but not statistically significant, trend. The changes in microbial biomass and activity following the change in soil pH could possibly be because of a change in soil microbial composition, and more detailed research is necessary. Compared with soil pH, soil organic matter content was another, more important, factor that directly restricted microbial growth because of the serious loss as a result of disturbance. As a practical application based on microbial aspects, introduction of some N-fixing tree species may be an active and effective measure to improve soil fertility and thus to accelerate restoration of the forest ecosystem in the karst region.  相似文献   

Validation and application of real-time polymerase chain reaction assays for representative rumen bacteria     

Satoshi KOIKE  Hiroyoshi YABUKI  Yasuo KOBAYASHI 《Animal Science Journal》2007,78(2):135-141

Real‐time polymerase chain reaction (PCR) assays for 11 representative rumen bacterial species were validated. The sensitivity was tested by using the serially diluted target 16S rDNA from respective bacterial species. The recovery of the target DNA and the assay reproducibility were determined using DNA from rumen fluid spiked with different quantities of the target. Minimum detection levels for the target were 10–100 copies in pure culture. The recovery of the added target ranged from 82.4 to 116.6%. The intra‐ and inter‐assay variations of each assay were <9.4 and <12.6%, respectively. Therefore, the real‐time PCR assays evaluated in the present study are considered to be sufficiently reliable for monitoring all 11 bacterial species in the rumen. The assays were then applied to the monitoring of the bacterial species attached to ruminally incubated rice straw. Among the monitored fibrolytic species, Fibrobacter succinogenes was found to be the most dominant, accounting for 2.61% of total bacteria after 24 h incubation. Selenomonas ruminantium and Streptococcus bovis, non‐fibrolytics, were detected on the rice straw at 8.96% and 1.16% of total bacteria, respectively. Such high levels of non‐fibrolytics on the plant fiber suggest a synergistic relationship between fibrolytics and non‐fibrolytics.  相似文献   

Soybean sowing date effects on weed communities in untilled and tilled fields in north-eastern Japan     

HIROYUKI KOBAYASHI  ATSUSHI OYANAGI 《Weed Biology and Management》2006,6(3):177-181

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