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1.
《齐鲁渔业》2014,(11):I0001-I0001
Added bagasse and Bacillus sp. to Litopenaeus vannamei intensive culture tank, the treatment groups were treatment A（added Bacillus sp.）, treatment B（added Bacillus sp. with crushing bagasse） and treatment C（added Bacillus sp. with crushing-steaming bagasse） respectively. To estimate the effect of addition of bagasse with Bacillus sp. on the culture environment and shrimp growth, the level of total ammonia nitrogen（TAN）, nitrite nitrogen and nitrate nitrogen, total amount of bacteria in the water and shrimp growth were determined. The result suggested that the TAN concentration in treatment B and C were significantly lower than that in treatment A during the early stage of the culture（P〈0.05）. The addition of bagasse with Bacillus sp. was contribute to the formation of bio-floccules. The concentration of bio-floccules in treatment B and Cwere 6.3-20 ml/L and 8.3-30 ml/L respectively, which were significantly higher than that in treatment A（2.7-8.3 ml/L） during the culture（P〈0.05）.The average weight of shrimp in treatment B and C were 8.56±0.21g and 8.84±0.26g respectively, which were significantly bigger than that in treatment A（7.66±0.40g） when harvest（P〈0.05）. 相似文献
2.
3种沉水植物对水华藻类生长的影响 总被引：11，自引：0，他引：11
Effects of three submerged macrophytes, Potamogeton crispus, Myriophyllum sp. and Ceratophyllum demersum on the growth of bloom algae were investigated. The results of the coexistence assay indicated that, Potamogeton crispus, Myriophyllum sp. and Ceratophyllum demersum inhibited significantly excessive growth of bloom algae. Of the three submerged macrophytes, Potamogeton crispus and Myriophyllum sp. have the stronger inhibition on bloom algae; at the relatively higher concentrations （Potamogeton crispus, Myriophyllum sp. and Ceratophyllum demersum fresh weight 80,80 and 160 g/L）, the aqueous extracts of fresh tissue of three submerged macrophytes can inhibit growth of bloom algae ; the growth of bloom algae was strongly inhibited by using dry powder; at the concentration of dry weight 20 g/L, the inhibitory effect by aqueous extracts of the dry powder of the three submerged macrophytes was beyond 50% ; the methanol extracts of the dry powder of three submerged macrophytes can inhibit growth of bloom algae at the relatively higher concentration. 相似文献
3.
《齐鲁渔业》2014,(9):I0001-I0001
Induction of Settlement and Metamorphosis of Sea Cucumber Apostichopus japonicus larvae by 5-HT Yang Ding-long et al. （ 1 ）
Abstract The larva Apostichopus japonicus individuals were exposed to solutions of 5-HT at different concentration. After induction, the rates of metamorphosis were then estimated. The results showed that 5-HT at the concentration 0.001, 0.01, 0.1, 1 mmol/L could increase the metamorphosis rate of sea cucumber larva after 12 h and 24 h induction. The optimum inductive effect of 5-HT was archived when the larva individuals were exposed in 0.1 mmol/L for 24 h, with the metamorphosis rate increment of 12.8 percentage. Key words 5-HT; sea cucumber larvae; metamorphosis; settlement 相似文献
Abstract The larva Apostichopus japonicus individuals were exposed to solutions of 5-HT at different concentration. After induction, the rates of metamorphosis were then estimated. The results showed that 5-HT at the concentration 0.001, 0.01, 0.1, 1 mmol/L could increase the metamorphosis rate of sea cucumber larva after 12 h and 24 h induction. The optimum inductive effect of 5-HT was archived when the larva individuals were exposed in 0.1 mmol/L for 24 h, with the metamorphosis rate increment of 12.8 percentage. Key words 5-HT; sea cucumber larvae; metamorphosis; settlement 相似文献
4.
甲胺磷、辛硫磷对坛紫菜叶状体的生理效应 总被引：8，自引：0，他引：8
In this paper, the effects of methmidophos and phoxim with different concentrations and schedule on soluble protein content and chlorophyl a (Chla) content in Porphyra haintanensis were studied under experimental and ecological conditions. The results showed as follows: (1) there were some time-effect and dose-effect relationships between the pollutants and Chla contents. The Chla content of most of groups decreased with the increasing of dose and prolonging of the exposure time. In the same concentration, the toxicities of phoxim to Chla content was stronger than that of methmidophos. (2) All concentration groups in this study didn‘t show the significant time-effect and dose-effect relationships between pollutants and the soluble protein. And there was no significant difference of the soluble protein content among various groups. 相似文献
5.
大菱鲆胚胎的玻璃化冷冻保存 总被引：3，自引：0，他引：3
Vitrification solutions were examined for their suitability of cryopreservation of turbot (Seophthulnms maximus) embryos. PMPI gave higher survival rate (75.68%) than other vitrification solutions and was considered to be suitable liar the cryopreservation of turbot embryos. The freezing point of the vitrification solutions consisted of PG and MeOH in the proportion of 3:2 was measured when the vitrification solutions were cryopreserved. It showed that the vitrification solutions with a cryoprotectant concentration of over 41% have no freezing point and the freezing points of vitrification solutions containing 33.33%-40% cryprotectants were between -32.4℃ and -65.4℃, The freezing point decreased with the increase of cryoprotectant concentration. The resistance of turbot embryos at different stages to the cryoprotectants was studied, It was found that the turbot embryos from 4-5 pairs somite to tail bud were more resistant to cryoprotectants and suitable to vitrify. A live embryo was obtained after cryopreservation in liquid nitrogen for 14h and was hatched out。 相似文献
6.
《齐鲁渔业》2013,(4):I0001-I0001
Effects of Adding Bacillus sp. Z5 in Diet on Growth, Immune Parameters and Anti-disease Ability of Litopenaeus vannamei
Abstract The el-tects ot addlngBaclllus sp Z5 in shrimp pellet with the amounts of 108CFU/g on growth, immune parameters and anti-disease ability of shrimp Litopenaeus vannamei were studied. The result shows that the shrimps grew faster in Bacillus treatment group and the yield was 24% more than that in the control. After 21 days, the activity of Phenoloxidase in Bacillus group significantly increased. After 42 days, 相似文献
Abstract The el-tects ot addlngBaclllus sp Z5 in shrimp pellet with the amounts of 108CFU/g on growth, immune parameters and anti-disease ability of shrimp Litopenaeus vannamei were studied. The result shows that the shrimps grew faster in Bacillus treatment group and the yield was 24% more than that in the control. After 21 days, the activity of Phenoloxidase in Bacillus group significantly increased. After 42 days, 相似文献
7.
草鱼加热过程中肌肉蛋白质的热变性 总被引：7，自引：0，他引：7
The variations of muscle tissus, peroxidase and Ca2^2 -ATPase activities and Vp (pasteurization value) were investigated with the fresh samples of grass carp ( Ctenopharyngodon idellus ) heated at different temperatures, thus revealing the mechanism of denaturation of muscle protein by heating. The experimental results showed the great difference in muscle tissue structure before and after the samples heated. In the initial stage of heating the water loss accounted for 50% of the total. When the samples were separately heated at 75, 85, and 95℃, fk values (dehydration curve slope) were 5, 4.1 and 1.7, respectively, while Vp reaching 40 minutes were 22, 8 and 5 min, respectively. As to the time for deactivation of peroxidase in the heated samples at the various temperatures, it varied from 38, 10 and to less than 6 min, respectively and the deactivation rates of Ca^2 -ATPase in 1 min were 50%, 88% and 100%, respectively. Consequently, the higher temperature the sample was heated, the faster rate of thermocon ductivity, the lower rate of water loss, and the faster rate of peroxidase deactivation it was. Also, the Vp for the least requirement of pasteurization ( Vp≥40min) was obtained. 相似文献
8.
盐度对黄鲷胚胎发育及早期仔鱼生长的影响 总被引：16，自引：0，他引：16
The effect of salinity on embryo and early larva development of Dentex tumiforns was discussed. Floating forms of egg in different salinities, optimal salinity for embryonic development and early larva growth was studied. The results showed: 1. In immobile condition, all eggs sank at salinity of 32.0, most of egg ssuspended in the middle of water at 34.0, and all eggs floated on the surface when salinity above 36.0. 2. Eggs did not hatch out at salinity of below 10.0 or above 60.0 and the death time of egg gradually moved up with increase or decline of salinity. Eggs hatched out at salinity range of 15.0 and 50.0, including abnormal larva. There was indistinct difference in speed of embryonic development (about 36-40h) within the salinity of 15.0 and 50.0. However the salinity had a great effect on larval survival after hatching and abnormal rate. The relation between hatching rate and salinity variation showed parabola but abnormal rate showed inverted parabola. The hatching rate was 81%-86% and abnormal rate of yolk sac larva was 27%-30% in suitable salinities of 27.0-39.0. The hatching rate was 89%-91% and abnormal rate was 13%-16% in optimal salinities of 33.0-36.0. The oil ball of abnormal larva was located in the central or front position. With increased extent of salinity, spondyle of larva bended and number of larva with arrhythmia increased. 3. The optimal salinities were 30.0-35.0 based on SAI. The test with SAI showed that SAI of early larvae was 41.25-47.53 at salinities of 30.0-35.0, the yolk and oil ball of 7-8 days larva was completely absorbed with a survival rate of 88%. 相似文献
9.
Shunsuke Moriyama Kiyoko Yamaguchi Tomomi Takasawa Hiroaki Chiba Hiroshi Kawauchi 《Fish physiology and biochemistry》2006,32(3):189-201
In an attempt to understand growth regulation in the Japanese eel, Anguilla japonica, we cloned insulin-like growth factor-I (IGF-I) cDNAs and examined their mRNA expression in several tissues. Two eel IGF-I (eIGF-I) cDNAs encoding preprohormones, eIGF-I-Ea1and eIGF-I-Ea2, were cloned from the liver by polymerase chain reaction (PCR). The preproIGF-Is were identical in signal peptide and mature IGF-I, but different in the E domain—eIGF-I-Ea2 mRNA was 36 bp longer than eIGF-I-Ea1 mRNA. Eel IGF-I was 83–94% identical with that of teleosts, 71% identical with that of dogfish, 87% identical with that of bullfrog and chicken, and 83% identical with that of humans. In both males and females the highest eIGF-I-Ea1 mRNA levels were observed in the liver, with detectable levels also found in the gills, heart, stomach, spleen, kidney, intestine, swim-bladder, muscle, and gonads. eIGF-I-Ea1 mRNA levels in the liver were higher in females than in males whereas in the intestine they were lower than in males. eIGF-I-Ea2 mRNA was detected in all the tissues examined and at similar levels in males and females. In this experiment higher eIGF-I-Ea1 mRNA levels were observed in the liver of larger glass eels than in those of smaller fish. eIGF-I-Ea2 mRNA levels were also higher in larger eels, although they were lower than IGF-I-Ea1 mRNA levels. Both eIGF-I mRNA levels in liver were positively correlated with the body size of the␣glass eels. Intraperitoneal injection of recombinant eel GH (reGH), 0.25 μg g−1 body weight, into glass eels resulted in a significant increase in both eIGF-I mRNAs in the liver 1 day after injection compared with control fish, but no elevation was observed 2 days after injection. Incubation of liver slices with reGH at concentrations of 10, 100, and 1,000 ng mL−1 for 24 h resulted in a significant concentration-dependent increase in the levels of both eIGF-I mRNAs. Higher levels of eIGF-I-Ea1 and Ea2 mRNA were observed in the gills ofseawater-reared eels than in those of freshwater-reared fish, but no differenceswere observed in the whole kidney. These results suggest that IGF-I is involved in the regulation of somatic growth and also in adaptation of the Japanese eel to seawater. 相似文献
10.
The growth and reproduction of Daphnia magna fed with Microcystis viridis and Chlorella spp respectively and 20% fish oil + 80% yeast and yeast were studied. The intrinsic rate of natural increase of Daphnia magna (rm) was 0.243 fed with Microcystis viridis, 0.301 with Chlorella spp., 0.244 with 20% fish oil + 80% yeast and 0.193 with yeast. The result showed that：Daphnia magna fed with Microcystis viridis had lower growth rates than that fed with Chlorella spp. an
d 20% fish oil + 80% yeast which both had full fatty acids. And the Daphnia magna fed with yeast was the lowest. So the fatty acids composition
of diet may affect the growth of Daphnia magna. This paper further examined total lipids and main HUFA (EPA and DHA) compositions of the continuous three generations of Daphnia magna (in order to get rid of t
he effects of former diet) fed with different of above diets (except the yeast). The result showed that:the three generations of the D. magna fed with Microcystis viridis had the lowest total lipids and the percentages of the HUFA (EPA, and no DHA) have a significant decrease and get the lowest EPA in the final experiment because of the very low HUFA especially EPA and DHA in Microcystis viridis. So the results indicate that Microcystis viridis with low HUFA made the lower growth rate, spawn
ing rate and hatching rate of Daphnia magna. 相似文献
11.
Association between the interannual variation in the oceanic environment and catch rates of bigeye tuna (Thunnus obesus) in the Atlantic Ocean 
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下载免费PDF全文 The environmental processes associated with variability in the catch rates of bigeye tuna in the Atlantic Ocean are largely unexplored. This study used generalized additive models (GAMs) fitted to Taiwanese longline fishery data from 1990 to 2009 and investigated the association between environmental variables and catch rates to identify the processes influencing bigeye tuna distribution in the Atlantic Ocean. The present findings reveal that the year (temporal factor), latitude and longitude (spatial factors), and major regular longline target species of albacore catches are significant for the standardization of bigeye tuna catch rates in the Atlantic Ocean. The standardized catch rates and distribution of bigeye tuna were found to be related to environmental and climatic variation. The model selection processes showed that the selected GAMs explained 70% of the cumulative deviance in the entire Atlantic Ocean. Regarding environmental factors, the depth of the 20 degree isotherm (D20) substantially contributed to the explained deviance; other important factors were sea surface temperature (SST) and sea surface height deviation (SSHD). The potential fishing grounds were observed with SSTs of 22–28°C, a D20 shallower than 150 m and negative SSHDs in the Atlantic Ocean. The higher predicted catch rates were increased in the positive northern tropical Atlantic and negative North Atlantic Oscillation events with a higher SST and shallow D20, suggesting that climatic oscillations affect the population abundance and distribution of bigeye tuna. 相似文献
12.
13.
Liping Li Rui Wang Wanwen Liang Xi Gan Ting Huang Yan Huang Jian Li Yunliang Shi Honglin Luo Ming Chen 《广西水产科技》2014,(1)
Previously, we reported 10 PEGE types of 85 tilapia Streptococcus agalactiae(GBS), which shifted from Streptococcus iniae in China, by using PEGE method. Presently, larger and more representative tilapia GBS were isolated, for the ?rst time in China, to characterize their serotypes and genetic diversities more precisely than had done before. 168 GBS strains were distributed in ?ve provinces of China, in which Guangdong, Guangxi and Hainan were the major ones, holding36.9%(62/168), 37.5%(63/168) and 19.6%(33/168), respectively. Serotypes, Ia, Ib and III, were observed in these strains and the most predominant one was Ia(95.2%), which mainly distributed in Guangdong, Guangxi and Hainan. Ia initially occurred in 2009, it shoot up to 32.1% in 2010,but decreased to 16.1% in 2011 before went up to 45.2% in 2012. Ib sporadically occurred during2007–2011, III onlyoccurred in 2012. 14 different PFGE types, including 4 new types(N, O,P and Q), were observed, in which B, D, F and G were the predominant types, holding 83.9%(141/168) of the total GBS strains. Ia corresponded to 11 PFGE types(A–H, N–P), in which type D predominated(51%). Ib represented 3 genotypes(I, J and Q) and III harbored only 2genotypes(N and F). Type N and Fsynchronously presented in Ia and III. In summary, the genetic diversity of tilapia GBS varied by serotypes and changed with geographical locations and years.Although Iastillpredominated, new rareserotypeIII alreadyoccurred in China. 相似文献
14.
In this experiment, a feeding trial was performed to determine the effects of fructooligosaccharide (FOS) on growth performance, digestive enzyme activity and immune response of Japanese sea bass, Lateolabrax japonicus juveniles (initial weight 38.3 ± 0.5 g), and the fish were examined following feeding with six levels of FOS (0, 0.5, 1, 2, 4 and 6 g/kg) for 28 days. Significant enhancement of weight gain (WG) and specific growth rate (SGR) was found in fish fed 1 g/kg FOS incorporated diets (p < .05), while the feed conversion ratio (FCR) in the 1, 2 g/kg FOS groups reduced significantly compared with the control (p < .05). Besides, the crude lipid in the 4, 6 g/kg FOS groups increased significantly compared with the control (p < .05). On the other hand, the erepsin and lipase activities significantly elevated in intestine of fish fed 2 g/kg FOS (p < .05) and the lysozyme activity in serum of fish fed 2 g/kg FOS were significantly higher than that in the control (p < .05). Moreover, the alkaline phosphatase activities in serum of fish fed 0.5, 1, 2 g/kg FOS were significantly higher than in control (p < .05). Regression analysis showed that the relationships between dietary FOS levels and either SGR, FCR, erepsin or lysozyme activities were best expressed by regression equations, and the optimal inclusion levels are 1.37, 1.80, 3.06, 3.11, 1.93 and 1.80 g/kg for SGR, FCR, erepsin, lipase, lysozyme and total superoxide dismutase activities, respectively. Overall, this study revealed that FOS incorporated diets could beneficial for L. japonicus culture in terms of increasing the growth, digestion and immune activities. Under the present experimental condition, the optimal supplementary level of FOS in the diet of L. japonicus is 1–3 g/kg. 相似文献
15.
Iciar Martinez Amaya Velasco Ricardo Pérez-Martín Eskil Forås Michiaki Yamashita Carmen G. Sotelo 《Journal Of Aquatic Food Product Technology》2013,22(4):289-297
The purpose of this work was to evaluate the suitability of a method based on the presence of two restriction sites (for Hae III and Hindf I) in the mitochondrial NADH dehydrogenase subunit 5 (mt ND5) gene to identify Scomber species. The evaluation was performed on 144 reference and market samples by sequencing of the entire 505-bp fragment of the mt ND5 gene and of a 464-bp fragment of the Kocher fragment of the cytochrome b gene (mt Cytb). Sequence analysis of any of the two fragments allows the identification of each of the four Scomber species, but S. japonicus and S. colias had the same restriction sites at the ND5 amplicon and would not have been differentiated by this analysis. Similarly, loss of the Hae III site in some S. scombrus individuals would have misidentified them as not being Scomber. All the market products were correctly labeled except one acquired in Spain labeled as originating in the Atlantic and containing S. japonicus. 相似文献
16.
Two gonadotropins (GtH; Qa and Qb) were purified by gel filtration and ion exchange chromatography from the pituitaries of Indian walking catfish (Clarias batrachus). The presence of GtH during purification was assessed by in vitro oocyte maturation and in vivo steroidogenic activity, and their identities were determined by elution profiles, molecular weight, biological activities and yield. The molecular weights of Qa and Qb were 37 and 42 kDa, respectively, and composed of distinct subunits (Qa: 20 and 14 kDa and Qb: 26 and 18 kDa). Polyclonal antibodies raised against Qa immunostained Qa, Qb and pituitary GtH cells. A competitive Qa‐ELISA was developed whose sensitivity was 6.25 ng mL?1 (1.25 ng well?1) with intra‐ (3.5%) and inter‐ (12.4%) assay coefficients of variation. Displacement curves parallel to the standard were obtained with plasma and pituitary extracts of catfish, Qb and carp GtHII. The assay was validated by measuring the plasma Qa levels after LHRH treatment and in relation to ovarian growth in the female catfish during different reproductive phases. Based on the results, Qa and Qb corresponded to fish LH and FSH respectively. The findings will increase the knowledge of the mechanisms controlling fish reproduction and identification of sensitive phases in fish in captivity for hormonal manipulation. 相似文献
17.
Controlled infection of Poecilia reticulata Peters (guppy) with Tetrahymena by immersion and intraperitoneal injection 下载免费PDF全文
下载免费PDF全文 G Sharon M Pimenta‐Leibowitz M C L Vilchis N Isakov D Zilberg 《Journal of fish diseases》2015,38(1):67-74
Tetrahymena is a protozoan parasite, which infects guppy, Poecilia reticulata Peters, and causes substantial economical losses in commercial farms worldwide. Studies of guppy infected by Tetrahymena require standardized infection protocols. The LD50 for Tetrahymena infection of guppies by intraperitoneal (IP) injection was calibrated, and the level obtained was 946 parasites per fish. Guppy infection with Tetrahymena by immersion, imitating the natural route of infection via the integument, was studied under normal or stress conditions. Exposure to cold and netting (CNI) and to cold only (CI) followed by immersion exposure to 10 000 Tetrahymena per mL resulted in 22.5% and 19.2% mortality, respectively, as compared to 14.2% and 10% in groups that were netted only (NI) or non‐stressed (I). Histopathology revealed that immersion infection resulted in a systemic infection. Lysozyme levels, measured 3 weeks after infection, were significantly higher in the CNI group (288 μg per mg protein) compared with CI‐, NI‐ and I‐treated groups (94.5, 64 and 62.3 μg mg?1, respectively). There was no evident parasite immobilization activity in body homogenates, suggesting no development of acquired immunity. Re‐infection by IP injection revealed no increase in protection in any of the treatment groups, mortality range of 56.3–75%, higher than in the non‐exposed control (40.6% mortality). 相似文献
18.
19.
Qin-Cheng Huang Di‐Gen Qin Bei‐Ping Tan Tao Du Yuan-Zhi Yang Qi-hui Yang Shu‐Yan Chi Xiao-hui Dong 《Aquaculture Research》2020,51(2):816-827
A 5 × 3 factorial growth trial was conducted to evaluate optimal dietary protein and lipid levels (dietary protein level, DP; dietary lipid level, DL) for juvenile Sillago sihama (S. sihama) (2.0 ± 0.02 g, initial weight). Fish were fed 15 diets containing 5 DPs (350, 400, 450, 500 and 550 g/kg) and 3 DLs (60, 90 and 120 g/kg) for 8 weeks. The interaction between proteins and lipids significantly influenced the feed conversion ratio, condition factor, body composition, antioxidant indices and lipase activity (p < .05). DP 450 g/kg showed the highest average final body weight. DPs 500 and 550 g/kg significantly decreased the protein efficiency ratio (p < .05). DL 120 g/kg showed the highest percentage weight gain. The low feed conversion ratio was found in diets P45L12, P55L9 and P55L12. Diet P45L12 showed high superoxide dismutase activities. DP 450 g/kg showed the lowest average malondialdehyde content. Lipase activity was increased by increasing DP (p < .05) with a fall at DP 550 g/kg. Under the present experimental conditions, the optimal DP for S. sihama was 450 g/kg under the DL 120 g/kg. 相似文献
20.
William King V David L. Berlinsky Craig V. Sullivan 《Fish physiology and biochemistry》1995,14(6):489-500
Plasma estradiol-17 (E2), testosterone (T), 17,20-dihydroxy-4-pregnen-3-one (DHP) and 17,20,21-tri-hydroxy-4-pregnen-3-one (20-S) levels were measured by radioimmunoassay (RIA) in white perch (Morone americana) and white bass (M. chrysops) that were induced to undergo final oocyte maturation (FOM) with human chorionic gonadotropin (hCG). Plasma DHP levels increased in females of both species in association with oocyte germinal vesicle migration (GVM) and germinal vesicle breakdown (GVBD) and decreased thereafter. Plasma 20-S levels also increased with oocyte GVM in white bass, but were several-fold lower than DHP levels. Circulating E2 and T levels were greatest during GVM and GVBD in both species and decreased to low levels during oocyte hydration and ovulation. Follicles from white perch and white bass which received a priming injection of hCG in vivo, produced both DHP and 20-S in vitro after exposure to hCG and their oocytes underwent GVBD. Ovarian incubates from unprimed fish of either species produced only E2 and T and their oocytes did not complete GVBD. Oocytes from unprimed bass, but not perch, matured when follicles were exposed to hCG in vitro. Both trilostane and cycloheximide blocked in vitro production of DHP and 20-S and oocyte GVBD by white perch follices. DHP and 20-S were equipotent inducers of FOM in the GVBD bioassay. None of several other structurally-related steroids tested were effective within a physiological range of concentrations. These results indicate a role for DHP and 20-S in the control of FOM in white perch and white bass. 相似文献