Vitamin contents of eggs that produce larvae showing a high survival rate in the Japanese eel Anguilla japonica     

Hirofumi Furuita  Tatsuya Unuma  Kazuharu Nomura  Hideki Tanaka  Tsuyoshi Sugita  & Takeshi Yamamoto 《Aquaculture Research》2009,40(11):1270-1278

This paper describes the relationship between the egg vitamin concentrations and the egg quality in the Japanese eel Anguilla japonica . No notable relation was found between any vitamin and the fertilization rate. Hatching and survival rates of larvae, however, significantly increased with an elevated level of egg vitamin C (VC). In contrast to VC, the relation between vitamins E (VE) and A (VA) concentrations and survival rate showed a clear peak, with a reduced survival rate at both higher and lower vitamin concentrations. The ratio of VE to lipid or highly unsaturated fatty acid (HUFA) in eggs positively correlated with hatching and survival rates of larvae. High-quality (HQ) eggs were determined as eggs that produced larvae having a survival rate higher than 80% at 8 days post hatch, and low-quality (LQ) eggs were determined as eggs that did not hatch. The level of VC of HQ was significantly higher than LQ. The results of this study suggest that HQ eggs, which produce larvae having a high survival rate, must have high levels of VC and VE/HUFA ratio and contain optimum levels of VA and VE in Japanese eel.  相似文献   

Availability of potato protein concentrate as an alternative protein source to fish meal in greater amberjack (Seriola dumerili) diets     

Fumiaki Takakuwa  Keinosuke Suzuri  Takao Horikawa  Kunpei Nagahashi  Shinichi Yamada  Amal Biswas  Hideki Tanaka 《Aquaculture Research》2020,51(3):1293-1302

Potato protein concentrate (PPC) is a promising candidate as a fish meal (FM) substitute because it has high protein and essential amino acid content. In the present study, we replaced FM in greater amberjack diets with PPC to investigate the effect on growth and feed utilization. Four isonitrogenous, isolipidic and isocaloric experimental diets were prepared by substituting 0, 20, 40 and 60% of FM protein with PPC (Control, P20, P40 and P60 respectively). The in vitro protein digestibility of protein in PPC was 88.8%, relative to 100% protein in the FM. The in vitro protein digestibility of protein in the experimental diets also decreased with increasing PPC and was lowest at 84.2% in P60. After the 7‐week feeding trial, final body weight, weight gain and thermal growth coefficient tended to decrease with increasing PPC and were significantly lower in P60 than in the control (p < .05). Further, fish fed with diets P40 and P60 showed significantly lower feed conversion and protein efficiency ratios than the control group (p < .05). In conclusion, the results suggest that PPC can replace up to 20% of FM in the diet of greater amberjack without compromising the growth performance or feed efficiency.  相似文献   

Similarity and differences in the physicochemical properties of lactate dehydrogenase isozymes from different tissues of Japanese sandfish <Emphasis Type="Italic">Arctoscopus japonicus</Emphasis>     

Kotomi Sugawara  Mizuki Nakagawa  Mika Yonezawa  Shigeyoshi Nakamura  Shun-ichi Kidokoro  Hideki Wakui  Wataru Nunomura 《Fisheries Science》2016,82(3):519-527

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Structure-Activity Relationship Study of the Neuritogenic Potential of the Glycan of Starfish Ganglioside LLG-3     

Megumi Yamagishi  Ritsuko Hosoda-Yabe  Hideki Tamai  Miku Konishi  Akihiro Imamura  Hideharu Ishida  Tomio Yabe  Hiromune Ando  Makoto Kiso 《Marine drugs》2015,13(12):7250-7274

LLG-3 is a ganglioside isolated from the starfish Linchia laevigata. To clarify the structure-activity relationship of the glycan of LLG-3 toward rat pheochromocytoma PC12 cells in the presence of nerve growth factor, a series of mono- to tetrasaccharide glycan derivatives were chemically synthesized and evaluated in vitro. The methyl group at C8 of the terminal sialic acid residue was crucial for neuritogenic activity, and the terminal trisaccharide moiety was the minimum active motif. Furthermore, the trisaccharide also stimulated neuritogenesis in human neuroblastoma SH-SY5Y cells via mitogen-activated protein kinase (MAPK) signaling. Phosphorylation of extracellular signal-regulated kinase (ERK) 1/2 was rapidly induced by adding 1 or 10 nM of the trisaccharide. The ratio of phosphorylated ERK to ERK reached a maximum 5 min after stimulation, and then decreased gradually. However, the trisaccharide did not induce significant Akt phosphorylation. These effects were abolished by pretreatment with the MAPK inhibitor U0126, which inhibits enzymes MEK1 and MEK2. In addition, U0126 inhibited the phosphorylation of ERK 1/2 in response to the trisaccharide dose-dependently. Therefore, we concluded that the trisaccharide promotes neurite extension in SH-SY5Y cells via MAPK/ERK signaling, not Akt signaling.  相似文献   

Root and crown rot of strawberry caused by Pythium helicoides and its distribution in strawberry production areas of Japan     

Yasushi Ishiguro  Kayoko Otsubo  Hideki Watanabe  Mikihiko Suzuki  Kiichi Nakayama  Takashi Fukuda  Masashi Fujinaga  Haruhisa Suga  Koji Kageyama 《Journal of General Plant Pathology》2014,80(5):423-429

Pythium species were isolated from seedlings of strawberry with root and crown rot. The isolates were identified as P. helicoides on the basis of morphological characteristics and sequences of the ribosomal DNA internal transcribed spacer regions. In pathogenicity tests, the isolates caused root and crown rot similar to the original disease symptoms. Multiplex PCR was used to survey pathogen occurrence in strawberry production areas of Japan. Pythium helicoides was detected in 11 of 82 fields. The pathogen is distributed over six prefectures.  相似文献   

Characteristic upregulation of glucose-regulated protein 78 in an early lesion negative for hitherto established cytochemical markers in rat hepatocarcinogenesis     

Sukata T  Uwagawa S  Ozaki K  Sumida K  Kushida M  Kakehashi A  Wanibuchi H  Miyata K  Ogata K  Fukushima S 《Journal of toxicologic pathology》2009,22(4):281-288

Previously, we reported α(2)-macroglobulin (α(2)M) to be a novel marker characteristic of rat hepatocellular preneoplastic and neoplastic lesions negative for hitherto well-established markers. In the present study, we further examined other candidate markers with specificity for the same type of lesions. Glutathione S-transferase-placental form (GST-P)-negative hepatocellular altered foci (HAF) were generated using a two-stage (initiation and promotion) carcinogenesis protocol with N,N-diethylnitrosamine (DEN) and either Wy-14,643 or clofibrate, two peroxisome proliferators. Microarray analysis using total RNAs isolated from laser-microdissected GST-P-negative HAF (amphophilic cell foci) and adjacent normal tissues was conducted along with immunohistochemistry and real-time RT-PCR. Staining for glucose-regulated protein 78 (GRP78) was detected in GST-P-negative HAF and hepatocellular adenomas, and slightly increased GRP78 mRNA expression was observed in the lesions by real-time RT-PCR analysis. Thus, an early increase of GRP78 expression in hepatocarcinogenesis is likely a feature of the amphophilic subset of HAF.  相似文献   

Comparison in taste and extractive components of boiled dorsal muscle and broth from half-smooth golden puffer Lagocephalus spadiceus caught in Japan with those of the same fish imported     

Hiroko Yamaguchi  Misako Nakaya  Gen Kaneko  Chie Yoneda  Toshitaka Mochizuki  Katsuya Fukami  Hideki Ushio  Shugo Watabe 《Fisheries Science》2013,79(2):327-334

The taste and extractive components of boiled dorsal muscle and broth prepared from half-smooth golden puffer Lagocephalus spadiceus caught in Japan and from those imported from China were compared. In the sensory test, the first taste, elasticity, and saltiness of boiled muscle from Japanese (domestic) fish were higher than those of the imported fish, whereas the orthonasal fishy smell of the imported fish was higher than that of the domestic fish. The first taste, aftertaste, retronasal fishy smell, sweetness, saltiness, and umami of the broth prepared from dorsal muscle of the domestic fish were higher than those of the imported fish, whereas orthonasal fishy smell and bitterness of the imported fish were higher than those of the domestic fish. Most panelists preferred the overall taste of the domestic fish to that of the imported fish. The concentration of trimethylamine in the trichloroacetic acid extracts from boiled muscle and broth of the imported fish was higher than that of the domestic fish, suggesting that this substance contributes to the orthonasal fishy smell of the imported fish.  相似文献   

Trophic structure in natural habitats of the abalone Haliotis discus hannai with distinct algal vegetation of kelp and crustose coralline algae: implication of ontogenetic niche shifts     

Nam-Il Won  Tomohiko Kawamura  Hideki Takami  Yoshiro Watanabe 《Fisheries Science》2013,79(1):87-97

The abundance, species composition, and stable isotope ratios of benthic organisms were investigated to determine the trophic structures in abalone (Haliotis discus hannai) habitats, which are characterized by contrasting vegetation of crustose coralline algae (CCA) and kelp beds. A size–frequency analysis revealed that juvenile abalones with shell lengths (SLs) smaller than ~30 mm primarily inhabited CCA beds, whereas adults were abundant in kelp beds. Stable isotope analyses indicated that CCA beds were composed of a single food chain, whereas kelp beds supported multiple food chains. The abalone were divided into three size groups to estimate potential species interactions during their ontogeny. A small gastropod, Homalopoma sangarense, was the most abundant species, but is suspected to be less competitive with abalone, especially in CCA beds. An abundant starfish Asterina pectinifera appeared to function as a potential predator of juvenile abalones in both CCA and kelp beds. We concluded that CCA beds are essential for immediate post-settlement processes of abalones, whereas kelp beds are more important for providing refuge and food sources for adult abalones. The present study highlights that ontogenetic niche shifting can be a successful life-history strategy to sustain the abalone population in a subtidal rocky shore ecosystem.  相似文献   

Molecular phylogenetic relationship of Tetraodon pufferfish based on mitochondrial DNA analysis     

Yoji Igarashi  Hiroyuki Doi  Yusuke Yamanoue  Shigeharu Kinoshita  Toshiaki Ishibashi  Hideki Ushio  Shuichi Asakawa  Mutsumi Nishida  Shugo Watabe 《Fisheries Science》2013,79(2):243-250

Pufferfishes belonging to the genus Tetraodon form one of the largest groups in the family Tetraodontidae. This group consists of more than 20 species distributed across freshwater, as well as brackish and coastal waters, of Africa and Southeast Asia. However, their phylogenetic and evolutionary relationships are still ambiguous. In the present study, mitochondrial genes encoding 16S rRNA and cytochrome b were sequenced for 17 Tetraodon species collected from various areas mentioned above. Supermatrix analysis based on the complete sequences of the two genes from Tetraodon species was performed using a tree with 50 tetraodontid species (including 7 Tetraodon species) as a backbone. The obtained phylogenetic tree classified Tetraodon species into three groups, correlating well with their habitats, such as Asian freshwater, Asian brackish water, and African freshwater. We also showed that salinity tolerance of Asian freshwater species T. cochinchinensis was apparently lower than that of Asian brackish water species T. nigroviridis, suggesting that the speciation of Tetraodon species in the Asian freshwater group was caused by the molecular evolution associated with osmotic regulation.  相似文献   

Partial characterization and ontogenetic development of pancreatic digestive enzymes in Japanese eel Anguilla japonica larvae     

Koji Murashita  Hirofumi Furuita  Hiroyuki Matsunari  Takeshi Yamamoto  Masahiko Awaji  Kazuharu Nomura  Jiro Nagao  Hideki Tanaka 《Fish physiology and biochemistry》2013,39(4):895-905

The pancreatic digestive enzymes, trypsin, chymotrypsin, lipase and amylase were partially characterized, and changes in their activities were examined during the initial ontogeny of Japanese eel Anguilla japonica larvae from 5 to 34 days post-hatching (dph). The pH optima of the eel larval enzymes were narrower than those other fish species; trypsin activity was highest at pH 9, chymotrypsin and amylase activities were highest at pH 7 and 8, and lipase activity was highest at pH 8 and 9. In an analysis of thermal profiles, the larval pancreatic enzymes had a high optimal temperature and high thermal stability, which are typical of fish from the tropics. At 12 and 13 dph, lipase activity and gene expression levels of trypsin (-a and -b), lipase and amylase decreased markedly, suggesting a marked change in larval metabolism at that time. These data could be useful in the development of artificial larval diets in Japanese eel.  相似文献