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用串叶松香草、西葫芦叶、意大利黑麦草饲喂－冬龄草鱼一个月，结果表明：串叶松香草的饲喂效果最佳，其铒料系数为１８．４６，增重率４８．１９％；西葫芦叶、意大利黑麦草的乌料系数分别为２１．３５、２ ３９．８１％、１１．４％。这三种牧草都具有适口性在好，利用率高的特点，值得在生产上推广。 相似文献
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[目的]本实验旨在探讨饲料中添加串叶松香草对团头鲂幼鱼生长性能、抗氧化能力和脂代谢的影响。[方法]实验选取240尾初始体重为(3.85±0.5)g团头鲂幼鱼,随机分为4组,每组3个重复,每重复20尾鱼。各组分别投喂串叶松香草添加水平为0%(对照组)、2%、4%和6%的实验饲料,饲喂8周后测定鱼体生长性能、肌肉组成、血液生化、肝肠抗氧化和肝脏脂代谢相关基因表达。[结果]研究发现,相较于对照组,4%和6%串叶松香草组的增长率、特定生长率显著降(P<0.05),6%组的终末均重显著降低(P<0.05),饵料系数显著增加(P<0.05)。在抗氧化能力方面,2%串叶松香草组肠道过氧化氢酶(CAT)、超氧化物歧化酶(SOD)显著高于对照组(P<0.05)。在脂肪沉积和代谢方面,4%和6%串叶松香草组肌肉粗脂肪含量显著高于对照组(P<0.05)。4%和6%串叶松香草组肠道脂肪酶活性显著低于对照组(P<0.05)。6%串叶松香草组血清中的甘油三酯(TG)、胆固醇(TC)、高密度脂蛋白(HDL-C)、低密度脂蛋白(LDL-C)均显著高于对照组(P<0.05)。4%和6%串叶松香草组肝脏中脂肪合成基因fas、srebp1c的表达量显著升高(P<0.05)。同时,6%串叶松香草组肝脏中脂肪分解基因lpl、cpt1a、pparβ的表达量显著下降(P<0.05)。应激24h后2%串叶松香草组累积死亡率低于对照组,肝脏SOD活性显著高于对照组(P<0.05)。[结论]总之,在饲料中添加2%的串叶松香草对团头鲂幼鱼的生长和饲料利用无不利影响,并且能够提高肠道的抗氧化能力,而当添加量增加至4%和6%时会抑制鱼体生长,并引起团头鲂幼鱼脂肪沉积。[意义]本研究结果为串叶松香草在水产动物饲料中的应用提供了参考。 相似文献
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甜菜碱对鲤鱼诱食促生长的研究 总被引：11，自引：0，他引：11
本研究了饲料中添加诱食剂甜菜对鲤鱼生长的影响。在鲤鱼饲料中添加0．0、0．1、0．3、0．5、1．0％的甜菜碱，试验用鱼体重为75．2％－82．7％，在1立方米的网箱中进行试验，试验期水温为18－24℃。结果表明，添加甜菜碱的各组日增重率与对照组相比分别提高6．77、19．55、21．80、24．81％。添加甜菜碱的各组饵料系数与对照组相比分别降低2．93、9．54、11．30、15．06％。0．3－1．0％甜菜碱的添加量对鲤鱼有显的诱食促生长作用，并提高了饲料转化率，从经济效益方面，0．3％的添加量是最好的。 相似文献
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以鲤鱼鱼种为试验对象,在饲料中分别加入0%、10%、20%、30%、40%的脱毒蓖麻饼,并用豆饼来调整各试验组饲料的蛋白质总量,经40天饲养,结果表明:添加20%脱毒蓖麻饼的饲料可以促进鲤鱼生长。 相似文献
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呼兰县渔业生产开发公司许卜渔场从1991年开始每年从黑龙江水产研究所购入高寒鲤鱼水花150万尾,以肥水下池发塘,经过10～15天培育,出池3.3cm以上规格夏花120万尾。几年来水花发塘成活率达80％以上,除自用以外,大部分外销。本场鱼种培育亩放高寒鲤鱼夏花3500尾,搭配花、白鲢、草鱼夏花1600尾,在无增氧设备的情况下,以驯化养鱼方式饲养,培驯大规格鲤鱼鱼种,鱼种出池规格达100～150g,平均规格为120g。现将试验结果报告如下。 相似文献
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松香草又称串叶松香草，属菊科多年生缩根性草本植物。能生长１２～１５年，它营养丰富，莲座叶丛期干物质中含粗蛋白质２３．６％，粗脂肪２％，粗纤维８．６％，粗灰分１９．１％，含氮浸出物４６．７％，钙３．２２％，磷６．２８％；蛋白质品质较好，消化率为８３％，是饲养草鱼、鳊鱼、团头鲂等草食性鱼类的主要青饲料。松香草是一种喜湿润的植物，生长最佳温度为２０～２８℃，具有耐寒、耐热、耐旱和抗病力强等特征，对土壤的要求也不严格，但在排水性能良好的土壤或偏沙性土壤种植产量更高。每２０～３０天刈割一次，刈割时，最好是… 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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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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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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Growth hormone (GH) and reproduction: a review 总被引：5，自引：0，他引：5
Florence Le Gac Odile Blaise Alex Fostier Pierre-Yves Le Bail Maurice Loir Brigitte Mourot Claudine Weil 《Fish physiology and biochemistry》1993,11(1-6):219-232
Interaction between growth and reproduction occurs in many vertebrates and is particularly obvious at certain stages of the life cycle in fish. Endocrine interactions between the gonadotropic axis and the somatotropic axis are described, the potential role of GH being emphasised. A comparative analysis of these phenomena in mammals, amphibians and fish, suggests a specific role of GH in the physiology of puberty, gametogenesis and fertility. It also shows the original contribution made by studies on the fish model in this field of investigations. 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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