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1.
研究了饥饿、投喂水丝蚓和人工饲料对杂交鲟(达氏鳇(♀)×施氏鲟(♂))(Huso dauricus(♀)×Acipenser schrenckii(♂))仔稚鱼生长、存活和消化酶活性的影响。结果显示:饥饿和投喂不同饵料对杂交鲟仔稚鱼的生长、存活、肥满度和消化酶活性影响显著。饥饿条件下,5 d后杂交鲟幼鱼生长基本停滞,10 d后负生长,与投喂饵料组的生长性能差异显著。消化酶活性方面,0~10 d,饥饿组的胃蛋白酶活性一直低于投喂饵料组,至20 d饥饿组的胃蛋白酶显著高于其它组;各处理组的脂肪酶活性变化规律各不相同,但是饥饿组的脂肪酶活性低于其他两组;各处理的杂交鲟幼鱼淀粉酶活性虽然有起伏波动,但是15 d后饥饿组快速升高并显著高于其他组。 相似文献
2.
研究探讨了大菱鲆(Scophthatmus maximus)幼鱼的昼夜摄食节律以及不同投喂时间对大菱鲆摄食和生长的影响。试验在室内流水养殖系统中进行,水温为(14±0.2)℃,饲喂鲆鲽类商品饲料。采用两种方法进行试验:Ⅰ.分段式投喂方法将一昼夜分为8个时段,每天每个试验缸连续投喂8次,大菱鲆幼鱼表现为18 h出现一次摄食高峰;Ⅱ.一次饱食投喂法将一昼夜分为8个时段,每个时段作为1个处理,每天每个试验缸投喂1次,大菱鲆幼鱼摄食高峰出现在15:00、21:00、0:00和3:00,投喂时间显著影响了大菱鲆幼鱼的日摄食率、特定生长率和饲料效率,15:00、18:00和3:00投喂的大菱鲆幼鱼特定生长率和饲料效率显著高于6:00、9:00、12:00、21:00和0:00投喂的各组试验鱼(P0.05)。结合生产实际,每天15:00—18:00时间段投喂大菱鲆幼鱼可显著提高其生长和饲料效率。 相似文献
3.
在水温14.8~21.2℃,比重1.008~1.013条件下,采用轮虫、微颗粒配合饲料、卤虫无节幼体及桡足类,以不同配比组成3组不同的饵料系列投喂香鱼仔、稚鱼。结果表明:采用轮虫 配合饲料-桡足类 配合饲料饵料系列的,其仔稚幼鱼生长速度和成活率均优于单纯使用生物饵料组成的饵料系列,并可降低育苗成本。 相似文献
4.
微粒饲料中鱼油n-3HUFA的分子结构对真鲷仔稚鱼生长、存活的影响 总被引：2，自引：0，他引：2
制备3种基本组成相同、添加不同类型鱼油的微粒饲料。将3种微粒饲料分别投喂真鲷(Pagrus major)仔鱼,探讨了微粒饲料中鱼油n—3HUFA的不同分子结构对真鲷仔、稚鱼生长、存活的影响。25d的养殖试验结果表明,虽然饲料2中n-3HUFA的含量高于饲料1中n—3HUFA的含量,饲料3中n—3HUFA的含量同饲料1中n—3HUFA的含量相等,但是用饲料1投喂的真鲷仔、稚鱼的全长、成活率要优于分别用饲料2和饲料3投喂的真鲷仔、稚鱼的全长、成活率。而且,用饲料1投喂的真鲷仔、稚鱼体内n-3HUFA和DHA的含量高于用饲料2和饲料3投喂的真鲷仔、稚鱼体内n—3HUFA和DHA的含量,这说明真鲷仔、稚鱼对天然鱼油的消化、吸收要优于对乙酯化鱼油的消化、吸收。 相似文献
5.
为研究不同投喂频率对绿鳍马面鲀幼鱼生长性能和肌肉品质的影响,在室内循环水养殖系统中,采用人工配合饲料,以1次/d、2次/d、3次/d、4次/d等4种投喂频率,对体质量(13.8±0.83)g的绿鳍马面鲀幼鱼进行了饲养试验,试验时长为42 d。结果显示,随着投喂频率增加,绿鳍马面鲀幼鱼的终末体质量呈逐渐升高的趋势,特定生长率呈先升后降的变化趋势,其中3次/d组幼鱼的特定生长率最高,显著高于1次/d组(P<0.05);饲料系数也随着投喂频率的增加而升高,3次/d组的饲料系数显著高于1次/d组(P<0.05),4次/d组的饲料系数显著高于1次/d组和2次/d组(P<0.05);肌肉品质方面,4次/d组幼鱼的肌肉粗脂肪含量显著高于1次/d组(P<0.05),不同投喂频率组间肌肉粗蛋白质含量和灰分含量无显著性差异(P<0.05)。综合考虑生长性能和肌肉品质指标,绿鳍马面鲀幼鱼适宜的投喂频率为日投3次。 相似文献
6.
不同饵料对日本囊对虾的生长与存活的影响 总被引：1，自引：0，他引：1
研究不同饵料对日本囊对虾生长、存活与饵料系数的影响,实验设置5个饵料种类,人工合成饲料、新鲜蛤仔肉、冰冻丰年虫成虫、人工合成饲料+新鲜蛤肉、人工合成饲料+冰冻丰年虫成虫,每个组合设置3个重复实验。结果表明,饵料对日本囊对虾生长性状、存活率与饵料系数均有显著影响(P0.05)。投喂人工合成饲料+冰冻丰年虫成虫组合的效果显著大于投喂人工合成饲料组合(P0.05),投喂新鲜蛤仔肉组合与投喂人工合成饲料组无统计学意义差异(P0.05);存活率的变化范围为(71.86±9.05)%~(86.89±3.11)%,投喂丰年虫组与投喂人工合成饲料+新鲜蛤肉组的存活率分别为最高和最低;饵料系数的变化范围为(2.00±0.06)~(2.87±0.12),投喂饲料+丰年虫组合与投喂人工合成饲料组的饵料系数分别为最低和最高。综合分析表明:投喂人工合成饲料+冰冻丰年虫成虫组合为最优组合,其次是人工合成饲料+新鲜蛤肉组合,在该条件下对虾生长速率较快、饵料系数低。 相似文献
7.
投喂三种商品性的鲑鳟鱼类饲料、一种试验性的甲壳动物饲料、与一种活饵料(颤蚓)对照，作美洲鲟幼鱼生长和存活试验，结果证明，某些加工饲料，特别是一种半潮湿性饲料，能作为美洲鲟开始摄食时头40天的饲料。虽然投喂半潮湿性饲料时鲟鱼的生长率比喂活饵料要低，但存活率仍一样；而且可以避免过去把鱼从喂活饲料转移到喂加工饲料时所产生的高死亡率。干饲料不能被很好利用，而且幼鱼生长率和存活率都很低。 相似文献
8.
研究不同投喂频率(1次/d,2次/d,3次/d,4次/d)对福瑞鲤(FFRC strain common carp)幼鱼摄食与生长的影响,试验周期为30 d。结果显示:当投喂频率从1次/d增加到4次/d时,福瑞鲤幼鱼的摄食率逐步提高,1次/d组的摄食率显著低于其他组(P0.05);体重增长率、体长增长率和特定生长率随投喂频率的增加均有不同程度提高,在4次/d时达到最高;饲料转化率逐步升高,1次/d组显著低于其他组(P0.05)。各试验组福瑞鲤幼鱼的个体体重/体长差异随着投喂频率的增加而先升后降,最终幼鱼的规格趋于一致。综合本试验结果,投喂频率对福瑞鲤幼鱼的摄食与生长存在显著影响,在4次/d的投喂频率下其摄食水平、生长性能、饲料转化效率及大小分化差异系数等均表现出较好状态。 相似文献
9.
一、要注意增加溶解氧水中含氧量是饲料系数的最大影响因素,对于投喂饲料为主的吃食性鱼类来说,在投喂同种饲料的情况下,放养相同密度的鱼种,在溶氧丰富的水体中比低氧水体中生长要快,饲料系数就低。 相似文献
10.
匙吻鲟幼鱼饵料培育及投喂技术 总被引：2，自引：0，他引：2
简要描述了匙吻鲟仔幼鱼摄食器官发育特征与摄食习性,总结出相关的幼鱼饵料池塘配套培育及投喂技术,关键是把握施肥时机、筛选并投喂足量适口饵料、严密监测浮游生物大小与种类组成。 相似文献
11.
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
12.
13.
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
14.
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
15.
Controlled infection of Poecilia reticulata Peters (guppy) with Tetrahymena by immersion and intraperitoneal injection 
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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
16.
The endemic, anadromous cyprinidChalcalburnus tarichi is the only fish species known to occur in alkaline Lake Van (Eastern Anatolia, Turkey). EightC. tarichi were maintained individually in Lake Van water (17 – 19°C; pH 9.8; 153 mEq·I–1 total alkalinity; 22 total salinity) and tank water samples analyzed for 24 h in 2 to 4 h intervals. At zero time, < 1µM ammonia was present and urea was undetectable in the tank water; at 24 h, total ammonia and urea made up 114±32 and 35±25µM, respectively. Over the experimental period, ammonia-N and urea-N excretion averaged 1041±494 and 607±169moles·kg–1 fish·h–1, respectively. The extent of urea excretion was highly variable between specimens. Uric acid excretion was not detectable.Urea was present at high concentrations in all tissues and plasma (25 – 35moles·g–1·ml–1) of freshly caughtC. tarichi; total ammonia content of the tissues was by a factor of 1.9 (liver) to 3.0 (brain) lower. High arginase activity (2.4±0.2 U·min–1·g–1) was detected in the liver ofC. tarichi but ornithine carbamoylphosphate transferase, a key enzyme of the ornithine-urea-cycle, was absent. Ureagenesis is likely through degradation of arginine and/or uricolysis. High glutamine synthetase activity (11±0.6 U·min–1·g–1) and low ammonia content in brain suggest that, like other teleosts,C. tarichi has an efficient ammonia detoxification in the brain, but in no other tissue.Nitrogenous waste excretion at alkaline pH is discussed. The ability ofC. tarichi to excrete high levels of ammonia at extremely alkaline pH is unique among teleosts studied so far. The mechanism of ammonia excretion under Lake Van conditions remains to be elucidated. 相似文献
17.
There has been growing concern about the overuse of antibiotics in the ornamental fish industry and its possible effect on the increasing drug resistance in both commensal and pathogenic organisms in these fish. The aim of this study was to carry out an assessment of the diversity of bacteria, including pathogens, in ornamental fish species imported into North America and to assess their antibiotic resistance. Kidney samples were collected from 32 freshwater ornamental fish of various species, which arrived to an importing facility in Portland, Oregon from Colombia, Singapore and Florida. Sixty‐four unique bacterial colonies were isolated and identified by PCR using bacterial 16S primers and DNA sequencing. Multiple isolates were identified as bacteria with potential to cause disease in both fish and humans. The antibiotic resistance profile of each isolate was performed for nine different antibiotics. Among them, cefotaxime (16% resistance among isolates) was the antibiotic associated with more activity, while the least active was tetracycline (77% resistant). Knowing information about the diversity of bacteria in imported ornamental fish, as well as the resistance profiles for the bacteria will be useful in more effectively treating clinical infected fish, and also potential zoonoses in the future. 相似文献
18.
Effect of iodophor disinfection of non‐hardened Salmo trutta eggs on their bacterial and fungus load 下载免费PDF全文
下载免费PDF全文 Franz Lahnsteiner 《Aquaculture Research》2017,48(7):3901-3909
This study investigated the efficiency of iodophor disinfection (135 ppm active iodine for 15–30 min) of non‐hardened Salmo trutta eggs against different groups of bacteria and against fungus. Egg samples were taken from non‐disinfected and from disinfected eggs, microorganisms were cultured on specific nutrient media and their mass was measured by turbidimetric methods. Bacteria and fungus mass of non‐hardened eggs could be reduced but not eliminated by iodophor disinfection with 135 ppm active iodine for 15 min. The extent of reduction was 47–65% (Experiment 1). The efficiency of disinfection increased with disinfection time as the reduction in bacteria and fungus mass was 40–55% after 15 min and 58–74% after 30 min (Experiment 2). Disinfection efficiency of iodophor solution diluted in water (reduction 49–57%) and of iodophor solution diluted in sodium chloride solution iso‐osmolar to the oocytes (reduction 52–61%) was similar (Experiment 3). The reduction in bacteria and fungus mass was persistent as it was 39–72% lower in embryos deriving from disinfected eggs than in embryos deriving from non‐disinfected ones (Experiment 4). In conclusion, the tested disinfection method is inadequate to eliminate pathogens completely but it could positively influence immune defence of eggs and embryos. 相似文献
19.
T. Citarasu K. Venkatramalingam M. Micheal Babu R. Raja Jeya Sekar M. Petermarian 《Aquaculture International》2003,11(6):581-595
The indiscriminate use of antibiotics and chemicals in shrimp hatcheries has led to biomagnification and that in turn could
lead to rejection of a whole consignment. The application of the bioencapsulation technique as a tool for curative treatment
in shrimp larvae was investigated. Herbs having antibacterial properties such as Solanum trilobatum, Andrographis paniculata and Psoralea corylifolia (methanolic extracts) were bioencapsulated in Artemia and fed to Penaeus monodon post larvae PL 1–25. The post larvae were reared in a medium inoculated with pathogenic bacteria such as Pseudomonas aeruginosa, Staphylococcus aureus, Salmonella typhi and Vibrio sp. Post larvae reared in the non-inoculated water and fed with non-enriched Artemia exhibited 90% survival, highest specific growth rate (12.43%) and reduced bacterial load. P. monodon reared in the bacterial inoculated water and fed with the non-enriched Artemia exhibited the lowest survival (10–30%), specific growth rate (8.42–9.1%) and increased bacterial load (2.86 × 103 to 3.76 × 105 cfu/g). The methanolic extracts of the herbs helped to increase survival and specific growth rate and reduced bacterial load
in the P. monodon culture system. Among the three herbal extracts, P. corylifolia enriched Artemia fed post larvae showed the tendency to higher survival (>50%), growth rate (11.5 averaged) and low bacterial load (1.12 × 105 cfu/g).
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献