HACCP体系在斑点叉尾鮰人工繁殖中的应用

在江西峡江和赣州进行了HACCP（Hazard Analysis and Critical Control Point）体系在斑点叉尾鮰（Ictalurus punctatus）人工繁殖中的应用研究.应用HACCP的基本原理,对整个斑点叉尾鮰人工繁殖过程进行危害分析,确立了亲鱼培育池的选择、亲鱼种质选择、亲鱼产卵池的选择、受精卵孵化、苗种培育、水质监测、饲料供应、日常管理等8个关键控制点,提出了相应的预防措施、关键限值、监控措施以及超过关键限值时的纠正措施,使各关键控制点处于人为控制之下.实现了斑点叉尾鮰人工繁殖按无公害化、规范化、标准化生产.     

斑点叉尾健康养殖模式

一、概述万安县建立了以"池塘培育斑点叉尾苗种,网箱养殖斑点叉尾成鱼"为核心的斑点叉尾健康养殖模式——万安模式。到2010年底,全县斑点叉尾养殖池塘达1万亩,网箱养殖突破10万米2,斑点叉尾产量达1万吨,总产值达1.3亿元。二、池塘培育斑点叉尾优质苗种技术要点1.鱼种培育池的条件与准备(1)池塘条件:鱼种池要求水源方便、水质良好、进排水设施完善;池底平坦,淤泥厚度小于20     

影响斑点叉尾亲鱼自然产卵率的关键因素研究

斑点叉尾是重要的经济养殖鱼类,本文从斑点叉尾亲鱼年龄、放养密度、产卵槽类型、饲料类型、池塘局部气候条件、池塘底质类型等方面对影响斑点叉尾自然产卵的关键因素进行了研究。结果表明,挑选4～5龄的亲鱼,在冬季气温、水温适当偏低的山区风口处建培育池,培育池底质为黏土硬底质或鹅卵石带沙底质,每667 m^2放亲鱼10～30组,全部投喂动物性饲料,用特制的土瓦罐作产卵槽,获得较高的自然产卵率。     

斑点叉尾高密度流水养殖试验

斑点叉尾俗称美国鱼,因其肉质鲜美、无肌间刺、高蛋白且不饱和脂肪酸含量高而广受消费者欢迎。我站于1992年引进原种斑点叉尾亲鱼,并于1993年繁殖成功,在池塘养殖中得到大规模推广。为了满足广大消费者的需求,提高斑点叉尾的品质和养殖效益,我站进行了高密度流水养殖斑点叉尾试验。经过半年多     

斑点叉尾鮰人工繁殖的几项要点

目前我国斑点叉尾鮰人工繁殖生产整体水平不高,苗种生产量一直上不去,据不完全统计,近几年全国斑点叉尾鮰苗种年生产量约在1000～2000万尾左右,造成苗种供求矛盾突出,影响了该鱼的推广养殖。笔者几年来通过对斑点叉尾鮰繁殖技术研究和生产实践,积累了一些技术经验,并每年生产近100万尾苗种供应各地养殖,出苗率由1990年25％提高到1993年的91％。现将斑点叉尾鮰人工繁殖的几个关键技术问题归纳一下,以供参考。 一、亲鱼培育 斑点叉尾鮰人工繁殖,生产上主要采用在原塘或产卵池放置产卵巢自然受精后收集卵块在孵化器进行人工孵化的方法。亲鱼培育是斑点叉尾鮰人工繁殖的     

斑点叉尾鮰的人工繁殖技术

阐述了斑点叉尾的人工繁殖技术，其中包括亲鱼池的条件、亲鱼的选择与培育、亲鱼的产卵以及鱼卵的孵化。     

斑点叉尾鮰的人工繁殖技术

阐述了斑点叉尾Ｈｕｉ的人工繁殖技术，其中包括亲鱼池的条件，亲鱼的选择与培育，亲鱼的产卵以及鱼卵的孵化。     

北方地区斑点叉尾鮰人工繁殖技术

2000年进行斑点叉尾鱼回人工繁殖技术试验,选择我国1997年从美国引进培育的美国密西西比品系斑点叉尾鱼回原种3龄鱼为亲体,经60d池塘暂养培育,获受精卵12 5×105粒,经28d室内孵化培育,共出池全长约2 5cm的鱼苗10 1×105尾,出苗率为80 6%。试验结果表明,斑点叉尾鱼回可以在北方地区进行人工繁殖。     

影响斑点叉尾(鲴)亲鱼自然产卵率的关键因素研究

斑点叉尾(鲴)是重要的经济养殖鱼类,本文从斑点叉尾(鲴)亲鱼年龄、放养密度、产卵槽类型、饲料类型、池塘局部气候条件、池塘底质类型等方面对影响斑点叉尾(鲴)自然产卵的关键因素进行了研究.结果表明,挑选4～5龄的亲鱼,在冬季气温、水温适当偏低的山区风口处建培育池,培育池底质为黏土硬底质或鹅卵石带沙底质,每667 m2放亲鱼10～30组,全部投喂动物性饲料,用特制的土瓦罐作产卵槽,获得较高的自然产卵率.     

斑点叉尾鮰的人工繁殖和苗种培育技术

我县水产技术推广部门年初引进斑点叉昆亲鱼400尾，开展人工繁殖试验，并取得成功，已育苗30万尾。现将该技术要点介绍如下：一、亲鱼培育1、亲鱼的选择。斑点叉尾的性成熟年龄一般是3年，但其繁殖力较低，体质差，通常选择4—5龄、体重2.5－3.5kg的亲鱼较为理想，体重超过4,5k     

Oocyte Diameter and Plasma Vitellogenin as Predictive Factors to Identify Potential Channel Catfish,Ictalurus punctatus,Suitable for Induced Spawning

This study monitors the progression of oocyte size and plasma hormone profiles of female channel catfish, Ictalurus punctatus, at monthly intervals to stage expectant ovulating, females for strip spawning. The “critical minimum” diameter of an oocyte to reach threshold maturity for channel catfish was 2.5 ± 0.21 mm. Monthly increases of oocyte diameters and plasma vitellogenin concentrations were linear until spawning. The reproductive performance of cannulated and noncannulated catfish did not differ, negating adverse effects of routine cannulation. This study suggests oocyte diameter in channel catfish can be used as a predictive factor to determine and stage potential broodfish suitable for hormone‐induced spawning.     

Application of Polymorphic Microsatellite Loci in a Channel Catfish Ictalurus punctatus Breeding Program

Abstract.— In order to monitor spawning success in earthen ponds, individual channel catfish Ictalurus punctatus broodfish were identified prior to stocking by genotype analysis with polymorphic microsatellite DNA markers. Individual spawns were collected and reared in a hatchery, and eight sac-fry per spawn were sampled for genotype analysis. Mendelian inheritance of microsatellite alleles was used to identify parents of each spawn. The probability of detecting a falsely matched offspring and spawning pair was >99%. Average spawning success was 44% (17–80%). Multiple spawning by males was found in seven of the eight ponds sampled. In these ponds, 47% of the males fertilized 2–6 egg masses over 1–8 wk, although most were 2–3 wk apart. Four different spawns were identified as two full-sib families and were probably due to interrupted spawning. Parent/offspring genotype analysis will be useful for production of half-sib families for estimation of genetic components of variation, estimation of effective breeding population, and selection of broodstock for multiple reproductive traits under natural spawning conditions.     

Suspending Mammalian LHRHa‐injected Channel Catfish,Ictalurus punctatus,in Individual Soft Mesh Bags Reduces Stress and Improves Reproductive Performance

Hormone‐induced spawning of channel catfish held communally in tanks is a reliable method to produce channel catfish, Ictalurus punctatus ♀ × blue catfish, Ictalurus furcatus ♂, F₁ hybrid catfish fry. However, mature catfish are crowded, and repeatedly handled during the process of induced ovulation. Repeated handling of gravid females is stressful and may impair ovulation, egg quality, and reproductive performance. Three trials were conducted to evaluate the effects of two methods of confining post‐hormone‐injected female channel catfish on stress response (cortisol concentrations) and reproductive performance: fish were either held individually while suspended in soft, nylon‐mesh bags or communally in a concrete tank. Percent of females ovulated to hormone treatment, relative fecundity, percent egg viability, and latency of channel catfish did not differ for fish in the two treatments. However, percent hatch and fry/kg of females was higher (P < 0.05) for fish held in bags that for fish held communally in tanks. Mean plasma cortisol response immediately prior to the first hormone injection (0 h) did not differ among fish groups in the two treatments. However, mean plasma cortisol concentrations were significantly lower (P < 0.05) for fish in the bag treatment at 16 and 36 h compared to fish held communally in tanks. Plasma estradiol levels (measure of oocyte maturation) were assessed at 0, 16, and 36 h after hormone injection; concentrations were (P < 0.05) higher at 16 h compared to 0 and 36 h; however, estradiol concentrations did not differ for fish held in the two treatments (P > 0.05). Suspending hormone‐injected broodfish individually in soft bags reduced stress response, improved egg hatching rate, and increased hybrid fry produced per kg weight of female broodfish. Using this simple technology, farmers can improve the efficiency of hatcheries producing hybrid catfish fry.     

Comparison of Culture Traits of Channel Catfish,Ictalurus punctatus,and Blue Catfish I. furcatus

Culture of channel catfish, "Ictalurus punctatus," accounts for virtually all catfish production. Recently, however, an increasing number of catfish farmers are growing or are considering the culture of blue catfish, "I. furcatus." Current and past research the compared the culture traits of channel and blue catfish are reviewed. Blue catfish could be potentially advantageous for certain farm environments. Strain effects in both species are important. In general, channel catfish grow faster to market size than do blue catfish. However, some strains of blue catfish grow faster than many strains of channel catfish. Blue catfish are more vulnerable to parasites such as "Icthyophthirius" and to bacterial infections such as those from "Flexibacter columnaris when compared to channel catfish. Blue catfish do not tolerate handling as well as channel catfish, and handling stress often leads to infections in blue catfish. However, blue catfish have high resistance to enteric septicemia of catfish caused by "Edwardsiella ictaluri" and to channel catfish virus when compared to channel catfish. Blue catfish are twice as vulnerable to harvest by seining than channel catfish, and have a higher dress-out percentage than most strains of channel carfish. Channel catfish tolerate lower dissolved oxygen levels than do blue catfish. Blue catfish require one more year to reach sexual maturity than do channel catfish.     

Effects of feeding rate and dietary protein levels on the breeding performance of female yellow catfish (Pelteobagrus fulvidraco)

Nutritional components and feeding strategies are multifarious amongst different producers, whereas they are just designed for fish farming but not suitable for improving the reproductive performance of broodfish. Yellow catfish (Pelteobagrus fulvidraco), an omnivorous species, is one of the important aquaculture fish in China. In order to improve the reproductive performance of female yellow catfish (119.86—134.54 g), four feeding strategies (0.5%, 0.75%, 1% and 1.5% BW/d) and three dietary protein levels (34%, 40% and 46%) were examined, respectively, in the two separate trials. The females with moderate feed restriction (1%) showed significant lower mesenteric fat index (MFI) and higher gonadosomatic index (GSI) than the satiation group (1.5%) and excessive feeding restriction groups (0.5% and 0.75%). Females with high MFI were difficult to be artificially propagated and showed a high mortality rate, whilst the fish at 1.0% feeding rate displayed low mortality rate and high ratios of spawned fish, as well as high percentages of fertilization and hatching. Meanwhile, the offspring of 1.0% feeding rate group showed a low malformation rate and high survival rate. Multiple spawning in the same breeding season are applied in yellow catfish to reduce the number of parent fish and increase the fry production, and gonadal recrudescence after spawning might be affected by different nutrient values including dietary protein levels. In the second trail, female yellow catfish were fed with 34%, 40% and 46% crude protein diet at 1% feeding rate for the second spawning, and the best reproductive and breeding performances were observed in the fish group with 46% crude protein diet. These results demonstrate that 1% feeding rate is optimum for the spawning and reproductive performance of female yellow catfish for the first artificial spawning, and 46% dietary protein group had the best reproductive performances in the second spawning.     

Influence of a Bacterial Amendment on Water Quality in Small Research Ponds for Channel Catfish,Ictalurus punctatus,Production

There has been considerable interest worldwide in applying bacterial inocula to channel catfish ponds for improving water quality, especially for acceleration of ammonia nitrogen oxidation through bacterial nitrification. The effects of a selected bacterial amendment on water quality in small research ponds for channel catfish production were evaluated at the E. W. Shell Fisheries Center, Auburn University, Auburn, Alabama. Three ponds were treated with the bacterial amendment Waste & Sludge Reducer? (Keeton Industries, Wellington, CO, USA) at three times the dose recommended by the manufacturer every 2 wk, and three ponds served as controls. There were nonconsistent minor differences in water quality between ponds treated with a commercial bacterial amendment and control ponds on several sampling dates. However, the average concentrations of water quality variables did not differ (P > 0.05) between the treatments and control. Channel catfish yield was not improved by applying the bacterial amendment. This study demonstrates that the bacterial amendment was of no benefit in improving water quality in well‐managed catfish ponds where stocking rates, feeding rates, and amount of aeration are balanced.     

Use of High Oleic Corn in Catfish Feeds

High oleic corn is a genetic variant that contains more protein, lipid, and oleic acid and less linoleic acid than regular corn. A study was conducted to compare weight gain and feed conversion of year-1 and year-3 channel catfish Ietalurus punctatus , and processing yield, body composition and frozen storage stability of year-3 channel catfish fed high oleic corn and number 2 yellow (regular) corn in extruded production diets. A commercial-type diet formulated to contain 30% protein and made with regular corn served as a control. A second diet contained high oleic corn in place of regular corn on an equal (air-dry) weight basis. A third diet contained high oleic corn in substitution for regular corn and part of the soybean meal to limit protein content to 28%, which was equal to that of the control diet. The experimental diets were fed to year-1 channel catfish (average initial weight 5.1 g) in aquaria for 10 wk and to year-3 channel catfish (average initial weight 1.07 kg) in 0.04–ha ponds for 14 wk. Substitution of high oleic corn for regular corn on an equal (air-dry) weight basis provided significant gain ( P < 0.01) of year-1 channel catfish but not of year-3 fish. Use of high oleic corn diets designed to be equal in protein content did not affect weight gain of either group of fish. Replacement of regular corn with high oleic corn caused a significant ( P < 0.01) reduction in linoleic acid but no significant ( P > 0.20) increase in oleic acid in the flesh of fish. Proximate body composition, dressing yield, fillet yield, visceral fat, and liver weight were not significantly different among treatments. Sensory scores of fillets frozen for 3 and 6 mo were not significantly different among treatments. Peroxide value, thiobarbituric acid number and free fatty acids increased with frozen storage time but were not different among treatments.     

五个斑点叉尾群体的微卫星遗传多样性分析

用8对微卫星引物对1997-2004年引进的5个斑点叉尾群体进行遗传多样性分析,计算并统计等位基因数、多态信息含量（PIC）、杂合度、遗传相似性系数、遗传距离等参数。实验显示8个微卫星位点在5个斑点叉尾群体中共检测到42个等位基因,平均期望杂合度为0.6338～0.7320,表明其遗传多样性程度处于中等偏上水平。平均多态信息含量为0.5756～0.6869,说明基因座为高度多态基因座（PIC〉0.5）。群体间遗传相似系数为0.7504～0.9203。聚类分析显示,04群体与其他4个群体的亲缘关系较远。结果表明：引进的5个斑点叉尾群体均具有较高的遗传多样性,遗传信息丰富,遗传变异大,为良好的育种材料。     

Development and Evaluation of an Ultrasound Imaging Reproductive Index Based on the Ovarian Cycle of Channel Catfish,Ictalurus punctatus

Commercial production of hybrid catfish (female channel catfish Ictalurus punctatus × male blue catfish Ictalurus furcatus) is reliant on interdependent biological, environmental, and technical procedures. This study addresses one of these critical components – the evaluation of channel catfish ovarian development based on sonographic analysis. The objectives were to: (1) develop a channel catfish ovarian ultrasonography index, (2) test the effect of the spawning trials on fertilization estimates of fish assessed using the ultrasonography index, and (3) evaluate the expected (hypothesized) and observed outcome of the ultrasonography assessments. Seven ovarian morphology classifications were developed based on ultrasonography of 915 channel catfish (N = 915 images), and 210 females were selected for spawning. The predictions based on the classifications prior to hormone injection showed a significant effect (P < 0.002) on the observed outcomes (viable or nonviable eggs). The probability of correct classification was 0.86–0.89 for Categories 3 (developing), 4 (advanced), and 5 (mature), and 0.93–1.0 for Categories 1 (undeveloped), 2 (underdeveloped), 6 (spawned), and 7 (atretic). The ultrasonography index covered the full range of ovarian dynamics (i.e., recrudescence through spawning). It provided an unobtrusive, direct method of ovarian assessment to work toward improving the efficiency of broodstock selection.     

Threadfin Shad Dorosoma petenense Effects on Water Quality, Phytoplankton, and Channel Catfish Production in Ponds

Threadfin shad Dorosoma petenense are often stocked into commercial catfish ponds for biological control of algae. It is thought that the fish will alter the phytoplankton community, improve water quality, and enhance channel catfish production. Co-stocking of shad and catfish is a common practice, although there is limited information regarding the effects of threadfin shad on pond dynamics and catfish production. To evaluate the influence of shad in catfish ponds, this study was conducted in ten 0.04-ha experimental earthen ponds near Auburn, Alabama. All ponds were stocked in April with 600 fingerling channel catfish Ictal-urus punctatus (13,200/ha) with a mean length of 10.4 cm (4.1 in). Additionally, five of these ponds were randomly chosen and stocked with 70 adult threadfin shad (1,750/ha) weighing a total of 3.3 kg (16.5 kg/ha). At harvest in November, an average of 1,284 threadfin shad (32,100/ha), weighing a total of 55 kg (1,375 kg/ha) were collected from each shad pond. Water quality was improved with the addition of threadfin shad to channel catfish ponds. Mean total ammonia-nitrogen was significantly lower and less variable in the shad treatment. Observed mean nitrite concentrations, though not significant, were lower in the shad treatment. The phytoplankton community of the shad treatment had significantly higher density, more taxa, and smaller organisms. Pond water in the shad treatment had higher projected early morning dissolved oxygen levels requiring less aeration. Channel catfish had significantly higher survival in the shad treatment, furthermore, though not statistically significant, observed mean fish production was higher and feed conversion ratio was lower than in the no-shad treatment.