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We conducted field monitoring of bedload transport rate associated with experimental sediment release in a natural channel to clarify behavior of the supplied sediment on mixed size bed. Observation of bedload rate at two sites along the 30 m channel reach revealed that downstream migration of finer particles delay compared with coarser particles. Ratio of the bedload sediment that deposited during the migration was higher for finer sediments. These behaviors of the mixed size particles were clear during passage of the sediment wave without changes in water discharge. Flashing peak of discharge that caused artificially by opening of the dam gate did not destroy channel bed structure including steps and pools formed by coarser sediments, and only small amount of bedload was mobilized. Both reach scale channel features including steps, pools, and riffles as well as fine scale features (i.e., armour coat) likely increased critical shear stress of particles and decreased bedload rate during our experiment. Extreme sediment supply induced two types of sediment deposition; (1) filling the pools in reach sales and (2) the intrusion of fine particles into the coarser sediment that formed an armour layer. The all grain size fractions can deposit as type (1) when shear stress of stream water is not enough to entrain bedload particles, while deposition type (2) occurs when finer sediment pass over channel bed on which armour coat is well-developed. Deposition of finer sediment into coarser sediment that forms armour coat is affected by grain size distribution of bed surface sediment. Thus, impact of the sediment supply on downstream channel depends on both bedforms and grain size distribution of bed surface sediment over which the supplied sediment pass. 相似文献
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Noboru TAKAESU Chihiro KANNO Kosuke SUGIMOTO Masashi NAGANO Akihisa KANEKO Yoriko INDO Hiroo IMAI Hirohisa HIRAI Munehiro OKAMOTO Mariko SASHIKA Michito SHIMOZURU Seiji KATAGIRI Toshio TSUBOTA Yojiro YANAGAWA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(3):429
In the Japanese macaque, semen has been collected by electro-ejaculation (EE), using the higher voltage stimuli compared to other species including genus Macaca. Semen coagulates immediately after ejaculation, which makes difficult to produce high-quality semen for artificial insemination. Recently, semen collection using urethral catheterization (UC) has been reported in carnivore and this technique may allow semen collection without coagulation in a less invasive manner. Further, the temporal preservation temperature and cooling rate of semen during cryopreservation affect post thawing sperm quality. In this study, to improve semen quality and quantity, as well as the animal welfare, semen collection was performed by EE with high (5–15 V) or low (3–6 V) voltage, UC and a combination of the two (EE-UC). It has been suggested that a high voltage is necessary for semen collection, but 10 V stimulation was effective enough and 15 V is for additional sperm collection. Also, liquid semen was collected by EE-UC and this could increase the total number of sperm. Further, to improve the post thawing sperm motility, semen was kept at four temperatures (4, 15, 25 and 37°C) for 60 min, and processed with two cooling procedures (slow cooling before second dilution and fast cooling after second dilution). Holding semen at 25°C and fast cooling after the second dilution maintained progressive motile sperm rate. The present results will contribute to the improvement of semen collection and animal welfare of Japanese macaques. 相似文献
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Naoki SUZUKI Sohei KANEKO Naoki ISOBE 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(3):325
This study aimed to determine whether causative pathogens in mastitic milk can be determined by Gram staining after the centrifugation of milk. Gram staining was performed using unconcentrated and concentrated milk cells. Using this method, we found that the background of microscopic image of unconcentrated milk cells was complex and bacteria were difficult to detect. In contrast, the background of the smears in the concentrated milk cells was translucent, and bacterial and somatic cells were clearly visible. The sensitivity and specificity of the Gram staining of concentrated milk cells were 84.4% and 86.0% and 50.0% and 94.5% for the detection of gram-positive and gram-negative bacteria, respectively. The presented method provides a simple and inexpensive means of determining mastitis-causing pathogens. 相似文献
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Fumihiro KANEKO Naoko KITAMURA Kenta SUZUKI Masaki KATO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(6):855
Wild boars (Sus scrofa) captured or found dead in Nagano Prefecture were surveyed for antibodies to Aujeszky’s disease virus (ADV), Erysipelothrix rhusiopathiae, porcine reproductive and respiratory syndrome virus (PRRSV), and Toxoplasma gondii. While all 168 samples tested were negative for anti-ADV antibodies and all 140 samples tested were negative for anti-PRRSV antibodies, all 190 samples tested were positive for anti-E. rhusiopathiae antibodies and 12 of 180 samples were positive for anti-toxoplasma antibodies. These results suggest that since E. rhusiopathiae and T. gondii cause zoonotic diseases, in addition to wild boars being a potential source of infection for domestic pigs, caution should be taken when handling wild boars or eating wild boar meat because of the possibility of human infection. 相似文献
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Satoshi KAMOTO Masahiro SHINADA Daiki KATO Masaya TSUBOI Sho YOSHIMOTO Ryohei YOSHITAKE Shotaro ETO Namiko IKEDA Yosuke TAKAHASHI Yuko HASHIMOTO James CHAMBERS Kazuyuki UCHIDA Shinji YAMADA Mika K. KANEKO Ryohei NISHIMURA Yukinari KATO Takayuki NAKAGAWA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(11):1795
Podoplanin is expressed in various human tumors where it promotes tumor progression, epithelial-mesenchymal transition, and distant metastasis. Podoplanin is also expressed in cancer-associated fibroblasts and induces tumor malignancy. The objective of this study was to evaluate podoplanin expression in various types of feline tumor tissues. Immunohistochemical analysis revealed that podoplanin was expressed in cells of 13/15 (87%) squamous cell carcinomas and 5/19 (26%) fibrosarcomas. Moreover, cancer-associated fibroblasts expressed podoplanin in most tumor types, including 18/21 (86%) mammary adenocarcinoma tissues. Our findings demonstrate that various types of feline tumor tissues expressed podoplanin, indicating the importance of the comparative aspects of podoplanin expression, which may be used as a novel research model for podoplanin biology. 相似文献
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Daisuke Fujita Rizza E. Santos Leodegario A. Ebron Mary J. Telebanco-Yanoria Hiroshi Kato Sohei Kobayashi Yusaku Uga Etsuko Araki Toshiyuki Takai Hiroshi Tsunematsu Tokio Imbe Gurdev S. Khush Darshan S. Brar Yoshimichi Fukuta Nobuya Kobayashi 《Field Crops Research》2009,114(2):244-254
A total of 334 introgression lines (INLs: BC3-derived lines) derived from crosses between a recurrent parent of Indica rice cultivar IR64 and 10 donor parents, including new plant type (NPT) lines IR65600-87-2-2-3, IR65598-112-2, IR65564-2-2-3, IR69093-41-2-3-2, IR69125-25-3-1-1, Hoshiaoba, IR66215-44-2-3, IR68522-10-2-2, IR71195-AC1, and IR66750-6-2-1, have been developed. These INLs with IR64 genetic background were characterized for eight agronomic traits: days to heading, culm length, leaf width, leaf length, panicle length, panicle number, 100-grain weight, and total spikelet number per panicle at the International Rice Research Institute from 2005 to 2007. To identify introgressed segments from the donor parents, genotypes of the 334 INLs were detected using more than 200 polymorphic simple sequence repeat markers. These segments detected on chromosomes 1, 2, 4, 5, and 6 were commonly introgressed across the INLs from more than four donor varieties. Based on the data of phenotype and genotype for the 334 INLs, associations between agronomic traits and introgressed chromosomal segments in the 334 INLs were investigated. A total of 54 regions for the eight traits were detected: seven regions for days to heading, eight regions for culm length, eight regions for leaf width, four regions for leaf length, six regions for panicle length, three regions for panicle number per plant, seven regions for 100-grain weight, and 11 regions for total spikelet number per panicle. Among them, the region on the long arm of chromosome 4 was associated with characteristics of the NPT such as long leaf, broad leaf, and high spikelet number. The developed 334 INLs with the IR64 genetic background will be useful materials for genetic analysis of agronomic traits. 相似文献
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Michiko NAKAI Manabu OZAWA Naoki MAEDOMARI Junko NOGUCHI Hiroyuki KANEKO Junya ITO Akira ONISHI Naomi KASHIWAZAKI Kazuhiro KIKUCHI 《The Journal of reproduction and development》2014,60(3):256-259
In pigs, the embryonic developmental ability after intracytoplasmic sperm injection (ICSI) is inferior to that resulting from
in vitro fertilization (IVF). We evaluated the timing of cell division up to blastocyst formation on
embryonic development after ICSI using either whole sperm (w-ICSI) or the sperm head alone (h-ICSI) and IVF as a control. At
10 h after ICSI or IVF, we selected only zygotes, and each of the zygotes/embryos was evaluated for cleavage every 24 h until
168 h. We then observed a delay in the 1st and 2nd cleavages of h-ICSI embryos and also in blastocoele formation by w-ICSI
embryos in comparison with IVF embryos. The rate of blastocyst formation and the quality of blastocysts in both ICSI groups
were inferior to those in the IVF group. In conclusion, the delay in cleavage of porcine ICSI embryos shows poorer embryonic
development. 相似文献
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ABSTRACT: During 1986–1989, the seasonal maturation and gonad index (gonad weight/body weight × 100) of adult Loxechinus albus were examined at nine sites, and the appearance of four-armed echinopluteus larvae was investigated at three sites off the eastern coast of Chiloé Island, Chile. Spawning occurred during November–January when the gonad indices fell to a minimum, the number of mature specimens decreased and four-armed larvae appeared, corresponding to the rise in water temperature. The number of four-armed larvae appearing at the northern site was markedly less than that at the southern site. The sea urchins matured in January and February immediately after spawning at many sites and a high percentage of maturation lasted for a long period at some sites. These findings are considered to be associated with high food availability and annual narrow ranges of water temperature. 相似文献
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Isolation of microsatellite markers by in silico screening implicated for genetic linkage mapping in Japanese pufferfish Takifugu rubripes 总被引：1，自引：0，他引：1
Satoshi FURUKAWA Hirohiko TAKESHIMA Taro OTAKA Toru MITSUBOSHI Kunio SHIRASU Daisuke IKEDA Gen KANEKO Mutsumi NISHIDA Shugo WATABE 《Fisheries Science》2004,70(4):620-628
ABSTRACT: The search for dinucleotide repeat microsatellites within scaffolds 1–25 of genome database JGI Fugu v3.0 for the pufferfish Takifugu rubripes revealed that 80% of microsatellite loci consisted of five to 13-fold repeats with locus-specific differences in density. Eleven out of 15 microsatellite loci isolated from the database with which genotyping using wild pufferfish was successfully performed showed polymorphism; that is, the means of the number of alleles and expected and observed heterozygosities at these 11 loci were 21.8, 0.915 and 0.829, respectively. It was confirmed that eight out of the 11 polymorphic loci were inherited through the Mendelian law and one pair of microsatellite loci derived from the same scaffold was linked. These results demonstrated that these loci are useful for constructing a linkage map in the pufferfish as DNA markers. 相似文献