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101.
We examined the effect of bottom feeding and net chasing as means to improve the maladaptive off-bottom swimming of hatchery-reared Japanese flounder Paralichthys olivaceus juveniles for stock enhancement. Three treatments were tested: (1) a bottom feeding treatment in which fish were fed near the bottom; (2) a net chasing treatment in which fish were chased by a hand net two to four times a day, and (3) a surface feeding treatment in which fish were fed from the surface (control treatment). Foraging behavior at the surface with surface feeding was analyzed 1 day before initiating these treatments and 2 weeks thereafter. A comparison of the pre- and post-treatments revealed that off-bottom swimming was less in the bottom feeding treatment and net chasing treatments. A comparison of off-bottom swimming in the bottom feeding treatment between the pre- and post treatments revealed that bottom fed fish showed less off-bottom swimming than surface fed fish. These findings suggest that fish behavior can be manipulated during the rearing period and that such manipulations can be used to improve the behavior of fish for release. 相似文献
102.
Radula development in abalone Haliotis discus hannai from larva to adult in relation to feeding transitions 总被引:1,自引:0,他引:1
ABSTRACT: The radula morphology of Haliotis discus hannai was examined by scanning electron microscope from the larval to the adult stage. The radula of competent larvae contained 11–13 transverse rows of teeth after 6–7 days at 20°C. The number of rows increased to 25–30 during the first several days after settlement, but then remained approximately constant throughout the post-larval period, increasing again in abalone larger than 4 mm in shell length (SL). In post-larvae < ~1 mm SL, only two pairs of lateral teeth (L1, L2) were present in the larval radula. An additional three pairs of lateral teeth (L3–L5) were added progressively as post-larvae grew from 0.9 mm to 1.9 mm SL. Marginal teeth were added steadily from one pair in larvae to 30–40 pairs at 3–4 mm SL, 70–80 pairs in 30–40 mm juveniles, and 70–90 pairs in 90–100 mm adults. The serrations on the working edges of the rachidian (R) and lateral teeth became less pronounced as the abalone grew. Nearly all serrations disappeared from the rachidian (R) and inner lateral teeth (L1, L2) by ~2 mm SL, and from the outer lateral teeth (L3–L5) by 20 mm SL. For abalone larger than 1.5 mm SL, the L3–L5 teeth became longer and more pointed, which increased the space between adjacent rows of teeth. Post-larvae < 1 mm SL had highly curved teeth with clearance angles of approximately or less than zero, whereas larger abalone had positive clearance angles. These radula developments appear to be related to transitions in feeding habits from microbial to macroalgal diets. 相似文献
103.
Jun Iguchi Yasuharu Takashima Atsushi Namikoshi Michiaki Yamashita 《Fisheries Science》2012,78(1):197-206
The complete nucleotide sequences of mitochondrial DNA (mtDNA) from four Seriola spp. (S. quinqueradiata, S. lalandi, S. dumerili, and S.
rivoliana) were determined with the aim of developing a species identification analysis method for discriminating between commercially
important Seriola spp. and other related species. In addition, the nucleotide sequences of the mitochondrial cytochrome b gene (Cytb) from five related but less expensive species in terms of market value (Seriolella brama, S. caerulea, S. punctata, Hyperoglyphe
japonica, and Rachycentron
canadum), which are often used as substitutes for Seriola spp., were determined. Restriction enzyme sites were examined by comparing the nucleotide sequences, and species-specific
primers were designed for PCR-based restriction fragment length polymorphism (RFLP) analysis. Based on the results of the
PCR amplification studies, the four Seriola spp. and the five related species tested could be categorized into three groups according to their PCR product pattern: a
373-bp product from the four Seriola spp., a 513-bp product from three Seriolella spp. and H. japonica, and a 204-bp product from R. canadum. In addition, RFLP analysis of the PCR products was able to differentiate these fish species. 相似文献
104.
Hiroshi Yamagata Tsubasa Saito Takezo Okamoto Kensuke Satomoto Tatsuya Mitsumoto Atsushi Wakita Maki Nakamura Takahiro Hayashi Yuichi Kuroiwa 《Journal of toxicologic pathology》2022,35(4):313
The carcinogenicity of 2,2’-[1,2-ethanediylbis(oxymethylene)]bis-oxirane (ethylene glycol diglycidyl ether; EGDE), 3-hydroxy-2-naphthoic acid (HNA), and acetoacetanilide (AAA) was investigated using a medium-term rat liver bioassay for an occupational safety assessment. F344 male rats were administered a single intraperitoneal injection of diethylnitrosamine (200 mg/kg body weight (bw)/day) and then starting 2 weeks later, they received EGDE at 6, 20, and 60 mg/kg bw/day, HNA at 20, 60, and 200 mg/kg bw/day, or AAA at 60, 200, and 600 mg/kg bw/day by oral gavage for 6 weeks. The animals in the positive control group received phenobarbital sodium solution (PB, 25 mg/kg bw/day) by oral gavage and those in the negative control group received a vehicle (water/corn oil) during the administration period of test substances in this model. All animals were subjected to two-thirds partial hepatectomy at week 3 and euthanized at week 8. Neither the number nor the area of hepatocellular foci positive for glutathione S-transferase placental form (GST-P) increased in any of the EGDE, HNA, or AAA treated groups. However, the number and area of GST-P-positive foci significantly increased in the positive control group treated with PB. The results indicate that EGDE, HNA, and AAA lack hepatocarcinogenicity in rats. 相似文献
105.
Yamashiro H Kumamoto K Wang H Yamashita Y Terada T 《The Journal of reproduction and development》2006,52(3):397-406
The objective of this experiment was to investigate whether the motility parameters and acrosome integrity of goat ejaculated spermatozoa are affected by collecting semen into tubes containing an extender, and thereby determine the significance of reducing contact between seminal plasma and the sperm membrane at ejaculation. Semen were collected from three goats into tubes containing 0, 1 or 10 ml extender, or collected into tubes containing 10 ml extender supplemented with 0.1, 1 or 5% BSA. Sperm motion parameters were evaluated immediately after collection, after washing, and during a 3-h thermal resistance test. Acrosome integrity was assessed using FITC-PNA staining. Semen collection into tubes containing 10 ml extender produced higher sperm motility, progressive motility, and acrosome integrity than that using a smaller volume of extender. Furthermore, collection into 5% BSA-containing extender exhibited higher sperm characteristics and maintained high sperm motility and progressive motility throughout incubation. In conclusion, semen collection into tubes with a large volume of extender, especially extender containing higher concentrations of BSA, improved the quality of ejaculated spermatozoa, strongly suggesting that the in vitro functional characteristics of the spermatozoa were abruptly modified by flash sperm contact with accessory sex gland fluid at ejaculation. 相似文献
106.
Lysosomal glycosphingolipid recognition by NKT cells 总被引:2,自引:0,他引:2
Zhou D Mattner J Cantu C Schrantz N Yin N Gao Y Sagiv Y Hudspeth K Wu YP Yamashita T Teneberg S Wang D Proia RL Levery SB Savage PB Teyton L Bendelac A 《Science (New York, N.Y.)》2004,306(5702):1786-1789
NKT cells represent a distinct lineage of T cells that coexpress a conserved alphabeta T cell receptor (TCR) and natural killer (NK) receptors. Although the TCR of NKT cells is characteristically autoreactive to CD1d, a lipid-presenting molecule, endogenous ligands for these cells have not been identified. We show that a lysosomal glycosphingolipid of previously unknown function, isoglobotrihexosylceramide (iGb3), is recognized both by mouse and human NKT cells. Impaired generation of lysosomal iGb3 in mice lacking beta-hexosaminidase b results in severe NKT cell deficiency, suggesting that this lipid also mediates development of NKT cells in the mouse. We suggest that expression of iGb3 in peripheral tissues may be involved in controlling NKT cell responses to infections and malignancy and in autoimmunity. 相似文献
107.
Distinct regional profiles of trace element content in muscle of Japanese eel Anguilla japonica from Japan, Taiwan, and China 总被引:1,自引:0,他引:1
Trace element distribution patterns were examined in Japanese eel from five Asian regions for the purpose of identifying the
elements and patterns that could be used to determine provenance. Distinctive patterns were found in eels from the Japanese
prefectures of Miyazaki, Kagawa, and Shizuoka, and from Taiwan and China. The levels of six trace elements, selenium, mercury,
copper, manganese, zinc, and arsenic, in muscle tissue varied among eels of different origins, and factorial analysis of the
elemental patterns showed that Factor 1 was attributable to selenium and mercury levels and Factor 2 to zinc and copper levels.
Multivariate analysis showed that the patterns of elemental composition in fish muscle were mainly differentiated by these
two factors. 相似文献
108.
Ryota Takeuchi Mitsuru Jimbo Fumika Tanimoto Mariko Iijima Hiroshi Yamashita Go Suzuki Saki Harii Yoshikatsu Nakano Ko Yasumoto Shugo Watabe 《Marine drugs》2021,19(3)
Many corals establish symbiosis with Symbiodiniaceae cells from surrounding environments, but very few Symbiodiniaceae cells exist in the water column. Given that the N-acetyl-d-glucosamine-binding lectin ActL attracts Symbiodiniaceae cells, we hypothesized that corals must attract Symbiodiniaceae cells using ActL to acquire them. Anti-ActL antibody inhibited acquisition of Symbiodiniaceae cells, and rearing seawater for juvenile Acropora tenuis contained ActL, suggesting that juvenile A. tenuis discharge ActL to attract these cells. Among eight Symbiodiniaceae cultured strains, ActL attracted NBRC102920 (Symbiodinium tridacnidorum) most strongly followed by CS-161 (Symbiodinium tridacnidorum), CCMP2556 (Durusdinium trenchii), and CCMP1633 (Breviolum sp.); however, it did not attract GTP-A6-Sy (Symbiodinium natans), CCMP421 (Effrenium voratum), FKM0207 (Fugacium sp.), and CS-156 (Fugacium sp.). Juvenile polyps of A. tenuis acquired limited Symbiodiniaceae cell strains, and the number of acquired Symbiodiniaceae cells in a polyp also differed from each other. The number of Symbiodiniaceae cells acquired by juvenile polyps of A. tenuis was correlated with the ActL chemotactic activity. Thus, ActL could be used to attract select Symbiodiniaceae cells and help Symbiodiniaceae cell acquisition in juvenile polyps of A. tenuis, facilitating establishment of symbiosis between A. tenuis and Symbiodiniaceae cells. 相似文献
109.
We investigated factors that accelerate dimethylamine formation in gadoid dark muscle. The degradation rate of trimethylamine-N-oxide into dimethylamine and formaldehyde during frozen storage was compared between ordinary muscle and dark muscle from
walleye pollock, southern blue whiting, and hoki. Dimethylamine was generated faster in dark muscle than in ordinary muscle
in each species, and it was produced most abundantly in hoki dark muscle compared with the other two species. We investigated
the mechanism that caused dimethylamine to be generated more abundantly in dark muscle during frozen storage, and found that
the amount of dark muscle nonheme iron, which catalyzes trimethylamine-N-oxide degradation, was higher than that in ordinary muscle in each species, and hoki dark muscle in particular contained
the highest levels of nonheme iron among these three species. Moreover, dark muscle in all three fish species had a higher
taurine content (known to accelerate dimethylamine formation) than ordinary muscle. These data suggested two candidate factors,
namely nonheme iron and taurine, that may accelerate dimethylamine generation during frozen storage. In addition, gel filtration
results suggested that walleye pollock dark muscle contains as yet unidentified low-molecular-weight agents that stably accelerate
dimethylamine generation. 相似文献
110.
Sasano Sachia Murakami Hiroaki Suzuki Keita W. Minamoto Toshifumi Yamashita Yoh Masuda Reiji 《Fisheries Science》2022,88(1):91-107
Fisheries Science - This study aimed at characterizing the distribution of black sea bream Acanthopagrus schlegelii, a major target fish of commercial and recreational fishing, using environmental... 相似文献