Influence of management protocols on carp growth under nursery conditions: relative importance of food and water quality

Twenty outdoor holding tanks (10 m–3 each), were filled with ground water and grouped into five feeding schemes: live zooplankton cultured outside the fish growing tank (LFS); direct nursery pond fertilization schedule in static (MS) as well as in exchanged water (EMS); intermediate conditions between the LFS and MS (IS); and supplementary food system using mixture (1:1) of finely ground mustard oilcake and boiled rice (SFS). Two hundred common carp (Cyprinus carpio) fry were introduced into each of the twenty outdoor tanks maintained at ambient temperature outside the laboratory. After 90 days of rearing, the fish were harvested and analysed for various growth parameters and food conversion efficiency. The average weight of carp attained in the LFS was significantly higher than that in the other four feeding schemes. The frequency distribution of final body weight of common carp showed the preponderance of large and small fish in the LFS and MS, respectively. Likewise, plankton intake by the carp fry was highest in the LFS. The rate of survival was much higher in the LFS as compared with the rest of the treatments. The water quality remained far better in the former than the latter. © Rapid Science Ltd. 1998     

Effect of fertilization frequency on pond productivity and fish biomass in still water ponds stocked with Cirrhinus mrigala (Ham.)

Four different fertilization frequencies, namely twice per week, once per week, twice a month and once a month, were used in ponds to assess their effects on nutrient release, pond productivity and fish biomass. All ponds received the same total fertilizer inputs during the experimental period of 60 days (cow dung 208.3 kg ha^?1 week^?1, TSP 9.8 kg ha^?1 week^?1, urea 6.0 kg ha^?1 week^?1). Studies have revealed that the highest values of fish biomass, specific growth rate (SGR), net primary productivity (NPP), plankton population and nutrients were observed in the ponds that were fertilized twice a month. A strong and significant correlation of fertilization frequency was observed with dissolved oxygen, biochemical oxygen demand (BOD), alkalinity, nutrient release, NPP, plankton density (no. L^?1), fish biomass and SGR. The linear relationship between NPP and fish biomass/SGR for all the ponds was strong (r²= 0.88). Sediment chemistry revealed that O‐PO₄, NO₃‐N, organic carbon and electrical conductivity (EC) increased significantly (P<0.05) with a decrease in the frequency of fertilization, while alkalinity and calcium were high in ponds that were fertilized twice a month.     

First year growth and survival of common carp in two glacial lakes

Abstract  Cohorts of common carp, Cyprinus carpio Linnaeus, were monitored from hatch through the next spring in two South Dakota, USA lakes to identify factors affecting year-class strength. Hatching occurred over 37- and 47-day periods in the two lakes. Common carp that hatched earlier achieved greater total lengths at the end of the first growing season (Brant Lake: r  = −0.84, d.f. = 77, P  <   0.001; Campbell Lake: r  = −0.87, d.f. = 78, P  <   0.001). Mean daily growth rates were approximately 1.0 mm day⁻¹ and similar between lakes. Total length was positively related to daily growth rate in the two lakes, indicating that members of the cohort that grew faster achieved greater total lengths by time of capture. Hatch date was inversely related to daily growth (fish hatched earlier grew faster) in one lake ( r  = −0.44, d.f. = 77, P  < 0.001) but not the other ( r  = −0.04, d.f. = 78, P  = 0.678), suggesting that length at the end of the growing season can be affected by length of growing season and growth rate. Overwinter survival of age-0 fish appeared to be size dependent because age-1 common carp length–frequency distributions from both lakes comprised only of the larger cohort members present the previous autumn.     

Effect of d-Lys6 salmon sGnRH alone and in combination with domperidone on the spawning of common carp during the late spawning season

The effect of [d-Lys6] salmon gonadotropin-releasing hormone alone (sGnRH) and in combination with domperidone, a dopamine antagonist, on the spawning of common carp, Cyprinus carpio, was investigated during the late spawning season (when mature fish stop spawning under natural conditions when males and females are put together). Fish were induced to spawn by [d-Lys6]-sGnRH salmon gonadotropin-releasing hormone analogue (sGnRH-X) only when injected in combination with domperidone at doses of 10 g kg-1 and 20 mg kg-1 body weight respectively. [d-Lys6]-sGnRH-X alone did not induce spawning at a dose as high as 100 g kg-1 body weight. Fish injected with domperidone alone did not spawn either. These results demonstrate that [d-Lys6]-sGnRH-X in combination with a dopamine antagonist is effective in inducing spawning during the late spawning season.     

沙棘植物资源的综合利用

为研究沙棘粉对黄河鲤生长性能、抗氧化能力和非特异性免疫的影响,实验选用初始体重约为7.55 g的黄河鲤450尾,随机分为5组,即对照组 (control 组)、高糖组 (HG 组)、高糖+0.1%沙棘粉组 (G-LSP 组)、高糖+0.3%沙棘粉组 (G-MSP 组)和高糖+0.5%沙棘粉组 (G-HSP 组),开展为期10周的养殖实验。结果显示,与高糖组相比,G-HSP组黄河鲤的增重率 (WGR)显著提高。与对照组相比,高糖组黄河鲤血清和肝胰脏中丙二醛 (MDA)含量升高,过氧化氢酶 (CAT)、超氧化物歧化酶 (SOD)活性和总抗氧化能力 (T-AOC)降低,而补充沙棘粉可减轻这些负面影响。高糖饲料抑制了肝胰脏和肌肉中nrf2 mRNA的表达水平,上调了keap1 mRNA的表达水平。沙棘粉对高糖引起的nrf2 mRNA表达水平的降低和keap1 mRNA表达水平的升高有显著的抑制作用。沙棘粉可显著提高受Nrf2调控的下游转录因子 (gr、cat、gpx和sod)的mRNA表达水平。此外,添加0.5%的沙棘粉能显著提高血清、脾脏和肠道中碱性磷酸酶 (AKP)、酸性磷酸酶 (ACP)、溶菌酶 (LZM)活性和白蛋白 (Alb)含量。另外,沙棘粉可以恢复因高糖饲料造成的脾脏和肠道中nf-κb、il-1β和tnf-α的mRNA异常表达。研究表明,沙棘粉可以缓解高糖饲料造成的氧化应激和炎症损伤,同时促进黄河鲤生长、增强其抗氧化能力和免疫力。结合本研究结果,在饲料中的建议添加剂量为0.5%。

     

饲料中高直链淀粉对大口黑鲈肠道物理屏障和菌群的影响

为了探究牛磺酸对脂质氧化饲料饲喂下黄河鲤生长性能和肠道健康的影响,实验先用等量的氧化鱼油 (记为OFO)替换基础日粮 (记为FO)中的新鲜鱼油,接着将不同含量 (0.4%、0.8% 和1.2%,质量分数)的牛磺酸分别加入OFO组饲料中 (分别记为T0.4、T0.8和T1.2),对初始体重为 (8.74±0.01) g的黄河鲤进行为期10周的养殖实验。结果显示,与FO组相比,OFO组的终末体重、增重率、特定增长率和饲料效率均显著降低。上述所有指标在T0.4、T0.8和T1.2组中均显著高于OFO组。适量牛磺酸可抑制氧化脂质饮食引起的nrf2 mRNA表达水平的降低和keap1 mRNA表达水平的升高,并且显著提高受Nrf2调控的下游转录因子 (gr、gpx和sod)的mRNA表达水平。牛磺酸还能缓解氧化脂质饲料引起的肠道消化酶活性、绒毛高度、绒毛宽度和肌层厚度的降低。另外,OFO组中肠道微生物组成的丰度和多样性显著降低,条件致病菌丰度明显升高,而有益菌的丰度却有所下降,这些不良现象在牛磺酸组中均得到明显改善。研究表明,牛磺酸可缓解脂质氧化饲料对黄河鲤造成的生长性能抑制、肠道组织结构破坏、消化功能下降及肠道菌群紊乱等不良影响。结合本研究结果,在氧化脂质饲料中牛磺酸的建议添加剂量为0.4%~0.8%。本研究为进一步探索牛磺酸对鱼类肠道的生物学功能奠定理论基础。

     

Koi herpesvirus and carp edema virus threaten common carp aquaculture in Croatia

Common carp (Cyprinus carpio) is a very important fish species for warm-water aquaculture in Croatia. All Croatian carp farms are subjected to a surveillance programme for the presence of koi herpesvirus (KHV), causing a deadly disease called koi herpesvirus disease (KHVD). However, there is no surveillance for other viral pathogens of importance like carp edema virus (CEV), a causative agent of koi sleepy disease (KSD). During regular testing within the KHVD surveillance programme, we tested samples for CEV simultaneously. The screening indicated possible outbreaks of KHVD and KSD. During 2016, KHVD broke out in an isolated area and soon thereafter a KHV eradication programme was successfully performed. However, during 2018 and 2019, two additional mortality events occurred in lakes in the southern part of Croatia during the spring. Samples from both events tested positive for CEV. An epidemiological investigation confirmed the introduction of infected carps from an infected farm to one of the lakes. To prevent the spreading of CEV into open waters, it is of utmost importance to introduce CEV testing before fish movement or to perform regular testing of all carp farms in the country to determine CEV prevalence for the purpose of implementation of control measures.     

Effects of dietary medium-chain triacylglycerols (tricaprylin and tricaproin) and phospholipid supply on survival, growth and lipid metabolism in common carp (Cyprinus carpio L.) larvae

The present study investigated the interaction of dietary medium-chain fatty acids (MCFA) and phospholipids (PL) on survival, growth and lipid metabolism in common carp larvae. Nine diets based on casein and dextrin and with a variable lipid part were tested in triplicate for 22 days post first feeding. The 3×3 design consisted of three triacylglycerols (3% of diet) combined with three different lipid supplements. Tested triacylglycerols were triolein (TOL), tricaprylin (TC8) and tricaproin (TC6), and lipid supplements were 2% soybean oil (low-fat diets without PL), 2% soybean lecithin (low-fat diets with 2% PL) or both 2% soybean lecithin and 6% TOL (high-fat diets with 2% PL).

In the first step, both TC6 and TC8 resulted in improved survival and growth rates compared to TOL, irrespective of the PL supply. In the second step, TC8 decreased survival and growth rates, whereas the difference between TC6 and TOL became less. Histological signs of impaired intestinal absorption of neutral lipids were evidenced in larvae fed TOL without PL and also in high-fat diets with 2% PL. The latter diets also resulted in poorer growth rates compared to low-fat diets with 2% PL. These results suggest that the quantitative PL requirement of larvae increases as the dietary level of long-chain triacylglycerols increases. Larvae fed TC6 or TC8 showed enlarged liver and hepatocyte volume and a decreased level of body neutral lipids. Based on β-hydroxybutyrate (β-HBA) measurements in whole larvae, TC8 was found to be more ketogenic than TC6. TC6 and TC8 affected differently the fatty acid profile of larval body neutral lipids. TC6 did not induce the appearance of MCFA, whereas TC8 feeding resulted in a low level of 8:0 and relatively high levels of 10:0 (3.8% of total fatty acids). Neither 8:0 nor 10:0 were found in larval polar lipids.

This study confirmed the essentiality of PL in common carp larval diets and underlines differences in the utilization of TC6 and TC8, which both initially stimulate growth during the first week, but only temporarily in the case of TC8.     

Reaction of common carp (Cyprinus carpio, L.) to oxygen deficiency in winter as an example for the suitability of radio telemetry for monitoring the reaction of fish to stress factors in pond aquaculture

The reaction of common carp (Cyprinus carpio L.) in an ice‐ and snow‐covered pond to depletion of dissolved oxygen (DO) in winter was recorded using radio telemetry. The carp moved from the deeper parts of the pond to the shallow areas near the tributary in search of better oxygenated water. Evidence was found that feeding occurred until December but ceased with the oxygen crisis. After the carp farmer started aeration to improve the oxygen supply, carp returned towards the deeper parts of the pond. The gross activity was significantly correlated with DO (P<0.001) and was not influenced by water temperature (P>0.05). The clear documentation of the carp's reaction to oxygen depletion suggests, that radio telemetry may be useful for investigating the effects of various stress factors on fish in pond aquaculture.     

Development of Quality Index Method Scheme for Common Carp (Cyprinus carpio) Stored in Ice: Shelf-Life Assessment by Physicochemical,Microbiological, and Sensory Quality Indices

ABSTRACT

Sensory methods are the most interesting methods to estimate fish quality. Among these, the recently developed quality index method (QIM) has gained popularity, as shown by the multiple publications of QIM schemes in the last years. The objective of this study was to create a new QIM scheme (QIM sensory table and corresponding point system) for the common carp (Cyprinus carpio), basing the definition of the rejection point on sensory, physicochemical (thiobarbituric acid reactive substances, total volatile basic nitrogen, pH, and color measurements), and microbiological criteria (counts of mesophiles, psychrotrophs, and Pseudomonas spp.). A new QIM scheme was developed and is proposed for use in the future; it will be useful for practical evaluations of carp freshness in all steps of the production chain, and it will contribute to a more effective use of the species as an alternative for human food supply.     

镉对鲤遗传毒性和外周血细胞数量的影响

将鲤(Cyprinus carpio)分别暴露于0.16、0.31、0.63、1.26 mg/L Cd2+溶液中,研究Cd2+对鲤外周血红细胞微核率、核异常率、红细胞和白细胞数量的影响,探讨Cd2+对鲤遗传毒性和外周血细胞数量影响的变化规律和趋势。结果显示:Cd2+对鲤红细胞微核率和核异常率的影响存在浓度-效应和时间-效应关系。与对照组相比,1.26 mg/L Cd2+组鲤在不同暴露时间的红细胞微核率和核异常率均极显著(P<0.01),核异常率在72 h显著(P<0.05)增加,72 h后表现为极显著(P<0.01)增加。Cd2+对鲤外周血淋巴细胞、单核细胞和嗜中性粒细胞比例的影响存在浓度-效应和时间-效应关系。相同Cd2+浓度下,鲤淋巴细胞比例随暴露时间增加先降低后上升,同一暴露时间淋巴细胞比例随Cd2+浓度增加而降低。相同Cd2+浓度下,鲤单核细胞和嗜中性粒细胞比例随暴露时间增加先升高后降低,同一暴露时间嗜中性粒细胞比例随Cd2+浓度增加而升高。研究表明,Cd2+对鲤具有遗传毒性效应,且随Cd2+浓度增加而增强。     

First feeding of common carp larvae on diets with high levels of protein hydrolysates

A 21 day feeding trial was carried out at 24 °C aiming to evaluate the effect of diets containing high levels of protein hydrolysates on growth, survival and body composition of common carp, Cyprinus carpio L., larvae since first feeding. Eight semipurified diets based on a fish protein hydrolysate (CPSP) with or without additional nitrogen sources, such as casein, casein hydrolysates or other hydrolysates from several origins, were tested, using a diet based on yeast as a reference. High survival rates of larvae were observed at the end of the trial for all experimental diets, ranging from 97% for the yeast diet to 71% when CPSP was used as the only nitrogen source. In terms of growth, the best results were achieved with the CPSP-casein diet (1:1) and the yeast-based diet (17.5 mm total length / 82.8 mg wet weight and 16.3 mm total length / 55.4 mg wet weight, respectively). Growth of larvae fed on diets with protein hydrolysates as the only nitrogen source was considerably lower than that of larvae fed a mixture of intact protein and protein hydrolysates.     

鲤胰蛋白酶原基因的电子克隆及生物信息学分析

为深入研究胰蛋白酶在鱼类中的生理功能和作用机制,利用生物信息学的方法,成功获得了鲤3种胰凝乳蛋白酶原cDNA序列(ccTRP1、ccTRP2和ccTRP3)并对其进行了序列分析。结果表明,三者均含有一个长度为729bp的开放阅读框(open reading frame,ORF),编码由242个氨基酸组成的胰蛋白酶原,其中包括15个氨基酸组成的信号肽和5个氨基酸(LDDDK)组成的激活肽。总平均亲水性GRAVY(grand average of hydropathicity)分析表明,三者均是亲水性蛋白。氨基酸比对结果显示,三者具备胰蛋白酶原的保守结构特征,如含有催化三联体氨基酸(His-57、Asp-102和Ser-195),12个半胱氨酸,位于底物结合口袋底部Asp-189和口袋开口处的Gly-216、Gly-226等。同时,鲤3种胰蛋白酶之间具有90%以上的同源性。进化树结果显示,鲤3种胰蛋白酶均属于Group I(阴离子型胰蛋白酶),且三者的进化距离不一致。     

饲料中添加蛋白酶Aquagrow对鲤生长和蛋白质消化酶活性的影响

为考察蛋白酶Aquagrow对鲤(Cyprinus carpio L)生长和蛋白质消化酶活性的影响,在鱼粉含量为6%的基础饲料中添加175 mg/kg的蛋白酶Aquagrow,饲养平均体重为48.7 g的鲤30 d.结果显示,基础饲料组(对照组)和添加蛋白酶组的鱼体增重率分别为99.4%、105.8%,饲料系数分别为1.85、1.75,添加蛋白酶提高了鲤鱼增重率6.4个百分点(P＜　0.05),降低了饲料系数5.4%(P＜　0.05),但对鱼体肌肉水分、粗脂肪、粗蛋白含量没有显著影响(P＞0.05);对消化酶活性的测定表明,添加蛋白酶可显著提高肠道组织蛋白酶活性和肠道内容物蛋白酶活性(P＜　0.05).上述研究表明,添加蛋白酶Aquagrow可提高鲤消化道蛋白酶活性,改善鲤生长性能.     

烟酸诺氟沙星和乳酸诺氟沙星在松浦镜鲤体内的药动学比较

应用高效液相色谱(HPLC)技术研究以相同浓度(30mg/kg)烟酸诺氟沙星和乳酸诺氟沙星对松浦镜鲤Cyprinus carpio specularis口灌给药后,药物在试验鱼血液、肝胰脏、肾脏中的药动学特征。相同给药剂量下,烟酸诺氟沙星和乳酸诺氟沙星在松浦镜鲤血浆中的血药浓度和时间关系均为一级吸收二室开放模型,吸收半衰期(t_(1/2ka))分别为0.061h、0.043h,消除半衰期(t_(1/2β))分别为29.969h、14.972h,达峰时间(T_(max))分别为0.327h、0.272h,达峰浓度(C_(max))分别为6.247mg/L、13.423mg/L,药时曲线下面积(AUC)分别为53.015mg·h/L、89.907mg·h/L,表观分布容积(V_d)分别为4.347L/kg、2.084L/kg。结果表明:在相同给药剂量下,乳酸诺氟沙星的吸收和消除速率均快于烟酸诺氟沙星,药物种类显著影响药动学特征。     

Determination of dosage of Azotobacter and organic fertilizer for optimum nutrient release, net primary productivity and fish growth in fresh water fish ponds

Four experiments were conducted in order to determine the optimum dosageof Azotobacter chroococcum vis-a-vis organic fertilizer(cow-dung) required for optimum pond productivity. Hydrobiological parameters ofpond water, Azotobacter survival (viable counts), netprimary productivity (NPP) and fish growth were monitored. Studies have revealedthat irrespective of the treatments, dissolved oxygen (DO) levels weresignificantly (P < 0.05) lowered on inoculating the ponds withAzotobacter. Alkalinity, O-PO₄,NO₃-N, turbidity, NPP, plankton population and fish growth weresignificantly (P < 0.05) enhanced in ponds inoculated withAzotobacter @ 100.0 ml pond^–1w^–2 in combination with cow-dung @ 10000 kgha^–1 y^–1. At higher or lower dosages offertilizers, the values in most of these parameters remained low. On the otherhand, total kjeldahl nitrogen and NH₄-N increased continuously. Ingeneral, viable bacterial counts decreased with increase in pH, however, therate of nitrogen fixation was not affected. Multivariate analysis of the data revealed a significantpositive correlation of nutrients (Total kjeldahl Nitrogen, NO₃-N andO-PO₄), with NPP and plankton populations. NH₄-N, however,showed a significant negative correlation with DO, NPP and plankton populations.Highest fish biomass and SGR also coincided with the highest NPP and planktonpopulations, revealing that a dose of 100.0 ml pond^–1w^–2 (for 25 m³ ponds) ofAzotobacter along with 10000 kg ha^–1y^–1 of cow-dung appears to be optimum for obtainingoptimum pond productivity and fish yield. Nutrients in the sediment(NO₃-N and O-PO₄) also followed similar trend. On theother hand, organic carbon increased continuously with each increase in thedosage of fertilizers. A decline in fish biomass and pond productivity at higherfertilizer dosages has been attributed to low DO, high NH₄-N and BOD.     

Dietary phosphorus prevents oxidative damage and increases antioxidant enzyme activities in intestine and hepatopancreas of juvenile Jian carp

This study was conducted to investigate the effect of dietary phosphorus on the intestine and hepatopancreas antioxidant capacity of juvenile Jian carp (Cyprinus carpio var. Jian). Jian carp, with an average initial weight of 7.17 ± 0.01 g, were fed with diets containing graded concentrations of available phosphorus, namely 1.7 (control), 3.6, 5.5, 7.3, 9.2 and 11.0 g kg^?1 diet for 9 weeks. Results showed that, in intestine and hepatopancreas, content of malondialdehyde (MDA), protein carbonyl (PC) and glutathione (GSH), capacity of anti‐superoxide anion (ASA) and anti‐hydroxyl radical (AHR), and glutathione reductase (GR), catalase (CAT), glutathione S‐transferase (GST), superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities were significantly affected by dietary phosphorus levels (P < 0.05). Regression analysis showed that significant quadratic responses occurred in MDA content and ASA, GST, GPx and AHR activities in intestine, GSH content and CAT and SOD activities in hepatopancreas (P < 0.05). These results indicate that optimal level of dietary phosphorus prevented oxidative damage and increased antioxidant enzyme activities in the intestine and hepatopancreas of juvenile Jian carp. The phosphorus requirement estimated from MDA using quadratic regression analysis was 5.7 g kg^?1 diet.     

Study on the adaptability of common carp (Cyprinus carpio) to diets from the perspective of digestion and absorption

As an ecologically sustainable aquaculture mode, the rice‐fish approach has been paid more attention in recent years. In rice paddies, there are plant and animal diet items available to fish, but it is not clear how common carp adapt to different diets. In view of this, common carp (initial weight 492.6 ± 30 g, n = 270) were randomly divided into three groups and fed with earthworms (group A), earthworms + duckweed (group M) and duckweed (group P) respectively. After 8 weeks under these feeding regimes, the intestinal digestive enzymes activities were assayed, and intestinal tissue sections stained with HE and AB‐PAS were used to observe the morphology. The results showed that the activities of trypsin and lipase were highest in group A, followed by group M and group P. Group A had greater intestinal fold height, fold width and fold absorption area than the other groups (p < .05), especially in the foregut. Meanwhile, the total number of mucous cells was largest in group P, followed by the groups M and A. Totally, activities and distributions of digestive enzymes, fold height, fold width, fold absorption area and number and distribution of mucous cells of common carp were affected by the type of diet. Based on these results, it was found that common carp has strong adaptability to diets, and it was speculated that the majority of digestion and absorption of protein was concentrated in the foregut, while for starch and cellulose, it was spread out along the whole intestine.     

鲢、鳙非经典生物操纵作用的研究进展与应用现状

鲢、鳙作为内陆水域主要的滤食性经济鱼类,通过对浮游生物的摄食行为抑制蓝藻水华的发生,这种干预现象在水域生态学领域称为非经典生物操纵。综述了鲢、鳙非经典生物操纵作用的研究与应用进展。目前关于鲢、鳙非经典生物操纵作用存在2种不同的观点。一种观点认为鲢、鳙大量滤食浮游生物,在控制蓝藻水华的同时还可将水中有机物转化为鱼产品移出,能够有效控制水体富营养化;另一种观点认为,放养鲢、鳙实际加快了水体营养盐的周转速率,在抑制蓝藻水华的同时加快了水体的富营养化进程。针对这2种不同观点开展的实验与调查表明,鲢、鳙放养对于抑制藻类水华的爆发作用明确,但同时导致浮游动植物小型化,浮游生物的数量会由于水体营养盐周转速率的加快而出现大幅波动。综合各方观点作者认为,鲢、鳙对于水体蓝藻水华形成的预防和抑制作用证据较为明确,但对于一定时期内水体营养盐变化的影响存在较大的不确定性,与水文条件、鲢鳙存量、集水区状况等有密切的关联。