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鲤鱼喹乙醇亚急性中毒的病理学研究 总被引：11，自引：0，他引：11
对鲤鱼进行了喹乙醇亚急性中毒的病理学研究。以1000mg/kg、2000mg/kg、3000mg/kg饲料的剂量进行了6周亚急性毒性试验，其发病率分别为35%、70%、92.5%；死亡率为27.5%、57.5%、82.5%。中毒鱼表现出特征性“应激性出血症”。 相似文献
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摄食不同喹乙醇水平饲料的鲤鱼肠道菌群的变化 总被引：2，自引：0，他引：2
本文研究了饲料中不同水平喹乙醇对鲤鱼肠道菌群数量及组成的影响。设计6组不同喹乙醇含量的饲料(0、200、400、800、1600和3200mg/kg)，对鲤鱼进行84d的饲养试验。试验结束时，各组随机取2尾鱼，分别对其前、中、后肠的细菌数量和组成进行了分析。结果发现：与对照组相比，投喂喹乙醇的试验组鱼肠道菌群数均有不同程度的下降，其中1600、3200mg／kg组的下降最为明显。从1600mg／kg开始前肠菌群数明显下降，在400mg/kg时中肠菌群开始下降较为明显，后肠菌群数在各试验组均呈下降趋势。在对照组检出的7种主要菌群也是构成各个实验组鱼肠道中的主要菌群，但这7种菌群在各组中的组成比例不同，其中鲤鱼肠道菌届中Aer属、Aci届的组成比例变化较大，800mg/kg(11．06％)、1600mg/kg(11．735％)和3200mg／kg(7．40％)组中Aer所占比例明显低于对照组(26．255％)，而800mg／kg(37．502％)、1600mg/kg(36．52％)和3200mg／kg(41．357％)组中Aci所占比例明显高于对照组(13．213％)。饲料中添加不同水平的喹乙醇可明显影响鲤鱼肠道主要菌群的数量及组成比例。 相似文献
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喹乙醇在鱼饲料和鲤鱼组织中的残留量 总被引：5，自引：0，他引：5
测定了喹乙醇在鱼饲料和鲤鱼组织中的残留量。用体积分数为 2 0σ/v的甲醇提取饲料中的喹乙醇。用乙腈 -乙酸乙酯 (体积比为 3∶2 )提取鱼组织中的喹乙醇。高效液相色谱条件 :Hypersil-C18为分离柱 ( 12 5mm× 4 0mm) ;流动相为 15σ/v甲醇 ;体积流量 1 0ml·min-1;紫外检测波长 2 60nm。喹乙醇在 2～ 2 0 μg·ml 1线性关系良好 ,相关系数 0 9996。测定下限为 2 0mg·kg 1。 相似文献
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稀土蛋氨酸配合物及稀土氯化物对鲤鱼毒性的比较试验 总被引：4，自引：1，他引：3
本报导了蛋氨酸配合物及稀土氯化物对鲤鱼毒性试验的比较结果，96小时半致死量分别为112．4mg/L和80．5mg/L。实验结果表明：稀土蛋氨酸配合物对鲤鱼的毒性比稀土氯化物低，都属低毒物质。 相似文献
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本试验旨在研究鲤鱼饲料中添加不同水平的酵母多糖对其生长性能的影响.试验选取240尾整齐规格、体质量相近、健康的鲤鱼随机分为4组,对照组鲤鱼饲喂基础饲料,试验1组、试验2组、试验3组鲤鱼分别饲喂添加0.5 g/kg、1.0 g/kg、2.0 g/kg的酵母多糖的基础饲料.结果表明:试验2组和试验3组鲤鱼的试验末重比对照组... 相似文献
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在鲤鱼饵料中添加不同水平的酵母多糖,研究对其抗氧化功能的影响.试验选取400尾整齐规格、体质量相近、健康的鲤鱼随机分为4组,每组包含10个重复,每个重复10尾鲤鱼.对照组鲤鱼饲喂基础饵料,试验1组、试验2组、试验3组鲤鱼分别饲喂含有0.5 g/kg、1.0 g/kg、1.5 g/kg的酵母多糖的基础饵料,预试验7天,正... 相似文献
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<正>喹乙醇又称喹酰胺醇,商品名为倍育诺、快育灵等,具有促进生长和抗菌作用,前些年广泛应用喹乙醇预混剂。但喹乙醇有中度至明显的蓄积毒性,对大多数动物有明显的致畸作用。农业部在2001年第168号公告中就作了严格规定:只能用于体重低于35kg的猪,添加量为50g/t的饲料,禁止用于家禽及水产养殖,但很多养殖者仍然违规使用。现将一起违规使用喹乙醇引起番鸭中毒的诊治介绍如下,供同行参考。 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