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691.
Ichiro?Nagano Seiko?Inoue Kenji?Kawai Syun-ichirou?OshimaEmail author 《Fisheries Science》2009,75(3):707-714
Pseudotuberculosis is a bacterial septicaemia caused by Photobacterium damselae subsp. piscicida in several marine fish species. Yellowtail Seriola quinqueradiata is the most sensitive fish species to this disease. The internal organs of naturally infected yellowtail exhibit whitish
spots, tubercle-like tissue structures, consisting of bacterial accumulations. There have been many trials for experimental
infection, however adequate method of infection that reproduces moderate mortality and primary clinical signs has not yet
established. Present investigation evaluated an immersion infection method by using logarithmic culture-phase bacteria resulting
in higher mortality than that using stationary culture-phase bacteria. Typical white spots on the spleen and kidney were also
observed constantly in dead fish. Transmission electron microscopy and fluorescent antibody microscopy showed bacterial clusters
not only in the spleen and kidney but also in the blood channels in the secondary gill filaments. These results were confirmed
repeatedly by plural experiments. The use of logarithmic-phase bacteria in immersion infection is an appropriate technique
to reproduce moderate mortality and primary clinical signs, which will be a reliable infection method also for the challenge
test of pseudotuberculosis vaccine. 相似文献
692.
Taeko Miyazaki Jun Kohbara Kenji Takii Yasunori Ishibashi Hidemi Kumai 《Fisheries Science》2008,74(2):314-321
ABSTRACT: In bluefin tuna aquaculture, collision of juveniles with the tank or net walls is a major cause of high mortality. This problem may be related to color sensibility of the visual mechanisms of this species. As a first step in understanding of color vision of Pacific bluefin tuna Thunnus orientalis , we applied a molecular technique and histology to study cone cell distribution in the retina of juvenile fish. We isolated three cone opsin genes encoding one blue-sensitive ( SWS2 ) and two green-sensitive ( RH2 ) visual pigments. In situ hybridization revealed that SWS2 mRNA is localized in the single-cone photoreceptors. The localization of the two RH2 signals in distinct cone cells was not determined, probably because of the high homology between the two RH2 genes. Single-cone photoreceptors appeared frequently in the ventral–temporal retina in approximately 80-mm fish and in the temporal retina in approximately 230-mm fish. These cone distributions may define a visual field with best color contrast vision in front and above the fish with a short wavelength (blue) reflecting target (sensed by single cones), and may be enhanced against the longer wavelength (green) background when fish see a target below them (sensed by double cones). 相似文献
693.
Kenji Ishihara Chiaki Oyamada Yoko Sato Toshiyuki Suzuki Masaki Kaneniwa Hiromi Kunitake Toshihiko Muraoka 《Fisheries Science》2010,76(6):1015-1021
Glycerol galactoside (GG; floridoside: 2-O-glycerol-α-d-galactopyranoside, and isofloridoside: 1-O-glycerol-α-d-galactopyranoside) is known to be a component of edible red seaweed nori. Recently, we have found that low-quality nori (color-faded
nori), which has a low protein content, contains a large quantity of GG. From further studies, we have also found that GG
has prebiotic characteristics in vitro. In this study, we evaluated the in vivo prebiotic activity of GG in rats. Dietary
GG selectively increased the cecal Bifidobacterium count in rats. Other indices of prebiotics, such as pH of cecal content, organic acid concentrations, and fecal weight, also
supported the existence of prebiotic activity of GG. The present data will also contribute to the development of a new method
of utilizing color-faded nori as a health-promoting foodstuff. 相似文献
694.
Upgrading of urea formaldehyde-bonded reed and wheat straw particleboards using silane coupling agents 总被引:3,自引:0,他引:3
Guangping Han Changwu Zhang Dongmei Zhang Kenji Umemura Shuichi Kawai 《Journal of Wood Science》1998,44(4):282-286
Reed and wheat straw particleboards bonded with urea formaldehyde (UF) resin were manufactured from two different material configurations (i.e., fine and coarse particles). The board densities were in the range of 0.550–.90g/cm3. The effects of particle size and board density on the board properties were examined. The properties of particleboard produced from fine particles were better than those made from coarse particles. An increase in board density resulted in a corresponding improvement in the board properties. The properties of OF bonded reed and wheat straw particleboards were relatively lower than those of commercial particleboards. Three silane coupling agents were used to improve the bondability between the reed and wheat particles and OF resin. Results of this study indicate that all the board properties were improved by the addition of silane coupling agent. The degree of improvement achieved from each coupling agent was different; epoxide silane was found to be more effective for reed straw particleboard, and amino silane was better for wheat straw particleboard. 相似文献
695.
Seung-Cheol Ji Osamu Takaoka Si-Woo Lee Jae-Ho Hwang Yang-Su Kim Katsuya Ishimaru Manabu Seoka Gwan-Sik Jeong Kenji Takii 《Fisheries Science》2009,75(3):665-672
The effect of dietary medicinal herbs on lipid metabolism and stress recovery was investigated in red sea bream Pagrus major. Fish (mean body weight 24.0 ± 0.2 g) were fed on test fish meal diets supplemented with either Massa Medicata (Mm), Crataegi
Fructus (Cf), Artemisia capillaries (Ac), or Cnidium officinale (Co), or with a mixture of the four herbs (HM) for 12 weeks. A control group was fed a diet without herbs in the same manner.
A high survival rate was observed in the herbal diet groups. The final mean body weight, feed efficiency, protein efficiency
ratio, and apparent protein and lipid retention in the Ac, Co, and HM groups were higher than those in the control and Mm
groups. Final carcass, hepatic lipid and triglyceride contents, and plasma triglyceride and nonesterified fatty acid levels
were lower in the Ac, Co, and HM groups compared to those of control and Mm groups. However, final hepatic phospholipid, plasma
phospholipid, and high density lipoprotein cholesterol levels were higher in the Ac, Co, and HM diets groups than in the control
and Mm groups. The Cf, Co, Ac, and HM groups showed faster recovery time in the 2-phenoxyethanol anesthesia test and a higher
recovery rate in the 10-min air exposure test than those of the control and Mm groups. Moreover, the Cf, Ac, Co, and HM diet
groups had a significantly lower plasma cortisol level than the control and Mm diet group, but the glucose level in the herbal
diet groups was higher than that in the control group after a 1-h air exposure. These results indicate that the addition of
medicinal herbs to the fish diet improved lipid utilization and stress recovery in red sea bream. 相似文献
696.
Kenji Fujino Mari Obara Hitoshi Kiuchi Hiroshi Shinada Tsutomu Nishimura Toshihiko Maekawa Yuji Hirayama 《Plant Breeding》2020,139(5):845-852
A series of DNA markers for various agronomic traits may accelerate the success of marker-assisted selection in practical plant breeding programmes. Here, we developed DNA markers for the blast resistance gene Pi-cd. In this study, we examined the effects of the Pi-cd locus on not only blast resistance but also agronomic traits in agriculture. We developed three pyramiding lines (PLs) coupling Pi-cd with three blast resistance genes, pi21, Pi35 and Pi39. The effect of Pi-cd on blast resistance was dependent on the coupled resistance genes. Then, we evaluated the effects of Pi-cd on 13 agronomic traits. Amylose content and 1,000-grain weight showed significant differences between the PLs and current commercial varieties, which had no negative effects on agronomic trait values. Furthermore, we investigated the distribution of genotype for the Pi-cd locus among varieties of upland rice. The KT genotype specific to rice blast resistance may be predominant in the varieties. The results suggested that Pi-cd has the potential to be useful for improving blast resistance in rice breeding programmes. 相似文献
697.
Amal Kumar Biswas Manabu Seoka Kiyotaka Ueno Kenji Takii & Hidemi Kumai 《Aquaculture Research》2008,39(5):457-463
Three photoperiods (12L:12D, 16L:8D and 24L:0D) were used to investigate the growth performance and stress response in red sea bream, Pagrus major (body weight 200–400 g). Fish were fed a commercial diet to apparent satiation, two times a day for 8 weeks. Fish exposed to a 24L:0D photoperiod showed a significantly higher weight gain (%) than those exposed to other photoperiods (P<0.05). The best specific growth rate and feed conversion efficiency were achieved at 24L:0D and 16L:8D, without significant differences among them. Although fish exposed to 16L:8D showed a significantly higher plasma level of cortisol than those exposed to other photoperiods in the third week, there was no major variation in the cortisol level among the treatments either at the sixth week or at the end of this study. There were no significant differences either in the haematocrit level or the plasma levels of glucose, total cholesterol and total protein among the treatments during this study. The results revealed that the growth performance of red sea bream reared from 200 to 400 g can be stimulated significantly using a continuous (24L:0D) photoperiod without any measurable significant stress response in fish. 相似文献
698.
Satoshi Kambayashi Kouji Minami Yuka Ogawa Takehiro Hamaji Chung Chew Hwang Masaya Igase Hiroko Hiraoka Takako Shimokawa Miyama Shunsuke Noguchi Kenji Baba Takuya Mizuno Masaru Okuda 《Canadian journal of veterinary research》2015,79(3):201-209
The DNA repair protein O6-methylguanine-DNA methyltransferase (MGMT) causes resistance to nitrosoureas in various human cancers. In this study, we analyzed the correlation between canine lymphomas and MGMT in vitro. Two of five canine lymphoma cell lines required higher concentrations of lomustine to inhibit cell growth by 50%, but their sensitivity to the drug increased when they were cultured with an MGMT inhibitor. Fluorometric oligonucleotide assay and real-time polymerase chain reaction of these cell lines revealed MGMT activity and high MGMT mRNA expression, respectively. We analyzed the methylation status of the CpG islands of the canine MGMT gene by the bisulfite-sequencing method. Unlike human cells, the canine lymphoma cell lines did not show significant correlation between methylation status and MGMT suppression levels. Our results suggest that in canine lymphoma MGMT activity may influence sensitivity to nitrosoureas; thus, inhibition of MGMT activity would benefit nitrosourea-resistant patients. Additional studies are necessary to elucidate the mechanism of regulation of MGMT expression. 相似文献
699.
Sota KOBAYASHI Toshiyuki TSUTSUI Takehisa YAMAMOTO Yoko HAYAMA Norihiko MUROGA Misako KONISHI Ken-ichiro KAMEYAMA Kenji MURAKAMI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(7):861-863
A cohort study was conducted to evaluate the risk of bovine leukemia virus (BLV)
transmission to uninfected cattle by adjacent infected cattle in 6 dairy farms. Animals
were initially tested in 2010–2011 using a commercial ELISA kit. Uninfected cattle were
repeatedly tested every 4 to 6 months until fall of 2012. The Cox proportional hazard
model with frailty showed that uninfected cattle neighboring to infected cattle (n=53) had
a significant higher risk of seroconversion than those without any infected neighbors
(n=81) (hazard ratio: 12.4, P=0.001), implying that neighboring infected
cattle were a significant risk factor for BLV transmission. This finding provides
scientific support for animal health authorities and farmers to segregate infected cattle
on farms to prevent spread of BLV. 相似文献
700.
Yasuhisa OISHI Kenji TANI Hiroshi NAKAZAWA Kazuhito ITAMOTO Tomoya HARAGUCHI Yasuho TAURA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(8):925-929
Liver contrast X-ray computed tomography (CT) has been used for evaluation of hepatic vessels for liver transplantation, liver lobectomy, interventional radiology and diagnosis of hepatocellular carcinoma in humans. However, there remains scant available anatomical information on normal hepatic vessels in the veterinary field. In this study, visualization of hepatic vessels was evaluated in 32 normal beagle dogs by X-ray contrast CT using triple phase images. The following hepatic vessels were clearly visualized: arterial, portal and hepatic veins. With regards to the running patterns of the portal vein and hepatic vein, there were no significant differences between the dogs. However, the hepatic artery exhibited some differences in each dog. In particular, the hepatic artery of the quadrate lobe and the right lateral lobe had many running patterns. The results of the present study could be useful for veterinary diagnosis, surgery and interventional radiology. 相似文献