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中国对虾幼体的能量代谢 总被引：20，自引：4，他引：20
近年来中国对虾(Penaeus orientalis)工厂化育苗技术的进步,已能使海捕亲虾与养殖越冬亲虾在人工控制的条件下产卵,然而虾卵孵化之后能否健壮地生长以及如何提高变态存活率,幼体的饵料起着关键的作用。生物饵料虽然效果好,但受到培养技术及设备等条件的限制,因此,目前育苗生产中的饵料仍以豆浆、蛋黄为主,辅以少量的生物饲料与配合饵料,以致幼体的抗病力差,变态存活率低。所以研究适合于中国对虾幼体营养需求的配合饵料很重要。至今有关日本对虾幼体营养的研究屡见报导,而中国对虾幼体的营养研究还未有报导。对虾营养的研究方法有分析虾体成分、梯度或正交法设计饲料试验以及能量代谢试验等。周洪琪(1990)通过能量代谢研究中国对虾亲虾的营养。Harris(1959)、Conover 相似文献
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随着对虾人工育苗的发展,对虾幼体饵料已成为人工育苗的关键,近年来,由于卤虫卵供应不足,价格上涨,且质量每况愈下导至育苗成本不断增加。国内外对对虾幼体的饵料进行了大量的研究,并成功地应用到生产当中的有微型胶囊饵料、粉状微颗粒饵料,但据我们的使用,人工配合微型饵料质量不稳定,在水中悬浮时间短溶散太快,使育苗水质严重污染,造成危害。1988年在卤虫卵价格上涨而孵化率极低(2～10%)的情况下,我们决定不使用卤虫育苗。在1500m~3的育苗水体中进行了以蛤肉代替卤虫幼体做为对 相似文献
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目前,在许多对虾育苗单位,把食母生作为对虾幼体的人工饵料,从而拓宽了对虾幼体的饵料来源。但是,在使用磺胺药防治虾苗疾病时,一定要慎用食母生。食母生是一种营养性药物,是酵母菌的干制品,它含有大量的维生素 相似文献
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蛋白质是对虾幼体最重要的营养素之一。关于对虾养成期蛋白质及其它营养素需求量的研究较多,但对其幼体蛋白质需求量的研究尚未见详细报道。蛋白质除了作为有机体增长的“构件”和组织修复的原材料外,还是对虾幼体重要的能量来源。育苗生产中,以轮虫为对虾幼体饵料,育苗效果最好。据此可以推测,蛋白质含量较高的饵料较适宜于对虾幼体的存活与生长。本研究利用不同剂型和不同蛋白质含量的饲料饲喂中国对虾的蚤状幼体和糠虾幼体,探讨其对蛋白质的需求量,旨在为对虾苗种生产和幼体饲料的研制提供科学依据。收稿日期：１９９９－０１－１… 相似文献
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华师斑节对虾幼体饵料，为华南师范大学生物系温说洪副教授和海康县两水一牧办公室主任曹耐工程师共同研制的饵料。该饵料经多次反复养虾试验观察，从小水体到大水体，从与进口料配合饲养，到以华师料单养，华师料均优于目前各种进口的幼体饵料，现已成功地培育出1．0～1．2厘米虾苗547。88万尾。 相似文献
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以酶学分析方法测定了中国对虾各期幼体几种消化酶活力，实验结果表明，在中国对虾幼体发育过程中，五种消化酶活力表现出四种变化模式，其中胃蛋白酶和类胰蛋白酶活力逐渐增大，淀粉酶活力呈下降趋势，纤维素酶和脂肪酶活力极微，在食性转换过程中，胃蛋白酶、类胰蛋白酶和淀粉酶出现较明显的变化。中国对虾幼体消化酶活力对饵料中的营养物质有着明显的适应性，而且饥饿实验表明消化酶活力受个体发育的影响。作者认为中国对虾幼体消 相似文献
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四角蛤蜊(Mactra quadrangularis)制作饵料,大量代替盐水卤虫卵,应用于中国对虾育苗生产。完全可以满足对虾幼体对动物饵料的需要,而且对虾幼体喜摄食、生长快、发育正常,育苗周期18天左右,平均茬口出仔虾每立方米水体30万尾,最高达70万尾。从无节幼体至仔虾出池的成活率一般在50～65％,与全用卤虫卵育苗效果相似。与卤虫卵、蛋黄、豆腐等饵料相比,具有加工方法简便、实用、供饵及时、成本极低等特点,开发了新的饵料源。 相似文献
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用螺旋藻配合饵料（S_PG营养剂）培育对虾幼体的效果 总被引：2，自引：0，他引：2
在对虾育苗中,为提高虾苗的成活率,促进幼体变态,降低成本,研制优质饵料巳成为当前生产中急待解决的问题。为此,我们与江西省农科院耕作所、中国农科院土肥所共同协作,采用了螺旋藻配合饵料饲喂对虾幼苗,两年来,在生产试验中取得了显著效果。现将试验情况报告如下: 相似文献
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中国科学院海洋研究所李光友等科技人员研究试用光合细菌(Photo synthetic bacteria)作为中国对虾育苗期饲料添加剂试验,取得明显效果。在对虾幼体饵料中添加培养7d的光合细菌,其对虾幼体的成活率明显高于添 相似文献
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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
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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
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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
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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
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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
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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
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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
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Cholecalciferol (Vitamin D3) increased plasma inorganic phosphate concentration in American eels,Anguilla rostrata, in a dose-dependent fashion. This response was more marked in phosphate loaded fish. In control as well as phosphate loaded
eels the hyperphosphatemic response to D3 was associated with a sharp reduction in renal phosphate clearance relative to14C-polyethelene glycol (PEG) clearance. Glomerular filtration and urine flow rates were not affected by D3. As renal phosphate clearance, even in phosphate loaded eels, never significantly exceeded that of PEG, it is suggested that
D3 reduced the relative clearance rate of phosphate by increasing renal phosphate reabsorption rather than by reducing the tubular
secretion of phosphate. 相似文献