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。     

提高斑点叉尾Hui亲鱼产卵率技术初报

斑点叉尾又名美国鱼 ,其优点是适应性广 ,抗病力强 ,生长快 ,个体大 ,易饲养 ,易捕 ,肉质细嫩 ,味道鲜美 ,经济价值高。 2 0 0 1年 ,我站共培育亲鱼 1 70组 ,实际产卵的有 1 51组 ,产卵率达 89.5%。现将我们的具体做法总结如下 :1　亲鱼池的选择、清整与消毒斑点叉尾亲鱼对水质条件要求较高 ,选择亲鱼池应靠近水源 ,水量充足 ,水质清新无污染 ,透明度 40ｃｍ以上 ,ＰＨ值 6.8-8.5,溶氧4ｍｇ/Ｌ以上 ;池塘面积为 3 -5亩 ,有效水位 1 .5-2 .0ｍ ,硬底或沙底 ,环境安静 ,有独立排灌系统 ,配备 1 .5ＫＷ增氧机一台。2　亲鱼选择2 .1　年龄…     

斑点叉尾鮰亲鱼池塘培育关键技术的研究

斑点叉尾鮰(Ictalurus punctatus)繁育亲鱼筛选可量参数:体长为头长的3.88~4.17倍、体长为体高的4.59~5.26倍、体长为尾柄长的5.73~6.73倍、体长为尾柄高的11.05~11.95倍、尾柄长为尾柄高的1.78~1.94倍。亲鱼培育产卵池塘适宜面积为0.20~0.53hm2,单位面积池塘内亲鱼承载量为2400~2550kg/hm2,3~6龄亲鱼放养密度为375~450组/hm2。投喂亲鱼饵料以含蛋白质36%人工配合饵料与动物性饲料相结合。亲鱼培育池塘水体昼夜变化的溶氧量为4.0mg/L以上、pH值为6.8~7.6、氨氮小于0.3mg/L、亚硝酸盐为0.01mg/L以下,亲鱼产卵率为80%以上。     

斑点叉尾鲴人繁及苗种培育技术研究

我们于2006年2～9月在邹城市洼陡水库实施了斑点叉尾鲴人工繁殖及苗种培育技术研究项目，共选择后备亲鱼100尾，7～8月间产卵，共获得卵块23块，产卵率为38。3％，平均受精率97％，孵化出卵黄苗22.5万尾，培育至3.5～4.0厘米时存活18.6万尾，培育率82.6％。     

斑点叉尾鮰亲鱼池塘培育关键技术的研究

斑点叉尾鮰(Ictalurus punctatus)繁育亲鱼筛选可量参数:体长为头长的3.88~4.17倍、体长为体高的4.59~5.26倍、体长为尾柄长的5.73~6.73倍、体长为尾柄高的11.05~11.95倍、尾柄长为尾柄高的1.78~1.94倍。亲鱼培育产卵池塘适宜面积为0.20~0.53hm2,单位面积池塘内亲鱼承载量为2400~2550kg/hm2,3~6龄亲鱼放养密度为375~450组/hm2。投喂亲鱼饵料以含蛋白质36%人工配合饵料与动物性饲料相结合。亲鱼培育池塘水体昼夜变化的溶氧量为4.0mg/L以上、pH值为6.8~7.6、氨氮小于0.3mg/L、亚硝酸盐为0.01mg/L以下,亲鱼产卵率为80%以上。     

斑点叉尾(鱼回)亲鱼饲料及规模繁育苗种研究

根据斑点叉尾(鱼回)亲鱼性腺发育情况不同季节的生态环境,配制不同营养水平的亲鱼配合饲料,分类放养,分期培育,有效提高了亲鱼成熟度。同时为了适应大规模繁育苗种的生产需要,不断完善繁育设施,改进繁育技术,使亲鱼繁殖期比当地提前30d,年繁殖鱼苗392万尾,推广2.5cm 以上鱼种220万尾,池存8cm 以上大规格鱼种150万尾,苗种收入573万元.     

斑点叉尾鲴人工繁殖试验

在3个面积1亩以下的试验池内,按密度为51一75kg/亩、性比1:1配对放养3.5kg/尾的亲鱼,使用自己配制粗蛋白含量38%的饲料强化培育,设置产卵巢,流水刺激诱导产卵,结果产卵顺利,平均产卵率42.9%,最高为66.7%.采用改进的孵化缸对卵块孵化,平均孵化率88.9%.     

提高斑点叉尾(鮰)亲鱼产卵量和产卵率关键技术

斑点叉尾(鮰)亲鱼产卵量和产卵率决定了孵化鱼苗数量和养殖规模,但在斑点叉尾(鮰)实际养殖过程中,亲鱼产卵量和产卵率往往不稳定,时高时低,严重影响斑点叉尾(鮰)鱼苗生产计划.     

池塘养殖斑点叉尾鲴鱼病防治技术

从斑点叉尾鲴的生物学性状出发，介绍了池塘养殖过程中常见病害的流行病学、发病机理和发病症状，并提出了针对性的防治措施以及斑点叉尾鲴的综合病防措施。     

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.     

An Evaluation of a Leuteinizing Hormone-Releasing Hormone Analog to Induce Spawning of Channel Catfish Ictalurus punctatus

The leuteinizing hormone-releasing hormone (LH-RH) analog, DAla⁶DesGly¹⁰ LH-RH-ethyl amide, delivered by intraperitoneal or intracranial injection was an effective agent for the induced spawning of channel catfish ( Icrulurus punctatus ) held in aquaria. A daily dose of 100 μg LH-RH analog (LH-RHa) per kg fish body weight was recommended as the dosage schedule of choice, but daily doses as low as 1 cg LH-RHa per kg fish body weight induced spawning of channel catfish. LH-RHa was as good or better than human chorionic gonadotropin or carp pituitary to induce spawning of channel catfish in aquaria. Sham-injected (control) channel caffish spawned in this study contradicting observations in earlier studies.     

斑点叉尾鮰养殖试验

斑点叉尾鱼回是美国主要淡水养殖品种 ,1 984年引入我国 ,经过多年研究及推广养殖 ,证实该种鱼适合我国大部分地区养殖。我场于 1 997年至 1 999年从外地购进鱼种 1 0万尾 ,分别在 4# 、5 # 、1 # 池塘进行小规模养殖 ,养殖中曾出现过因营养缺乏而发生的烂尾、神经痉挛、畸形 ,甚至停止生长、死亡等现象 ,经过会诊治疗 ,调整饲料配方取得明显的效果。1　试验条件与方法1 1　池塘条件本试验池选用的是渔业养殖公司二组的4# 、5 # 、1 # ,面积分别为 3亩、3亩、5 9亩 ,形状为长方形 ,平均水深 1 7ｍ。池塘水源为本水库底层水 ,每口池都能排…     

不同水温下强力霉素在斑点叉尾(鱼回)体内的残留消除规律

研究不同水温(18±1)℃和(28±1)℃下,强力霉素在斑点叉尾(鱼回)体内的残留消除规律.以20 mg/kg鱼体重连续口灌斑点叉尾(鱼回)5 d,于停药后第1、3、5、7、9、12、15、24、30、40天分别将斑点叉尾(鱼回)处死后取肌肉(加皮)、肝脏、肾脏3种组织,采用高效液相色谱紫外检测法测定斑点叉尾(鱼回)组织中强力霉素.结果表明,强力霉素在斑点叉尾(鱼回)体内的消除速度与水温有密切关系,不同水温下相同组织,相同水温下不同组织中强力霉素的消除速率不同(P＜0.05).高水温时强力霉素在斑点叉尾(鱼回)体内消除快,表明水温对斑点叉尾(鱼回)体内的药物代谢有明显的影响,强力霉素残留的消除速度随水温降低而减慢;与其他组织相比,强力霉素在肝脏中的消除最慢.因此,若将肝脏作为强力霉素在斑点叉尾(鱼回)体内残留的靶组织计算休药期,在(18±1)℃和(28±1)℃时,按欧盟和中国规定的动物组织中强力霉素在肝脏中最高残留限量300μg/kg计算,从食品安全角度来分析,建议休药期分别为55 d和30 d.若按强力霉素在可食组织肌肉(加皮)中最高残留限量300 μg/kg计算休药期,建议休药期分别为22d和19 d.本研究旨为不同水温条件下制定强力霉素在斑点叉尾(鱼回)体内的残留限量和休药期提供理论依据.     

Studies on Vaccination of Channel Catfish,Ictalurus punctatus,Against Edwardsiella ictaluri

Enteric septicemia of cattish (ESC), caused by the bacterium Edwardsiella ictaluri, has become the most significant disease problem affecting the commercial channel catfish, Ictalurus punctatus, industry in the United States. Although antibiotics are used extensively for the control of ESC, there are inherent problems associated with their use. Consequently, experiments were initiated to evaluate the effectiveness of vaccination program that used immersion and oral delivery methods to administer a killed E. ictaluri vaccine to fry and fingerling channel cafish. In a preliminary pond study with laboratory challenge, mortality in a group vaccinated with a combination of immersion and oral procedures was only 5.0% in both high- and low-dose challenges. This was significantly different (P c 0.01) from non-vaccinated controls, which had 46.7%mortality in the lowdose challenge and the 6 1.7% mortality in the highdose challenge. This corresponds to relative percent survival (RPS) values of 89.3 and 91.9 respectively. Subsequent field trials further indicated the efficacy of a vaccination program for the prevention of ESC in channel catfish. In 1987-1988, a field study was conducted using 12 commercial ponds, with three replicates of four treatments. The four treatments included vaccination by immersion only, oral only, a combination of both immersion and oral procedures, and non-vaccinated conwols. Relative percent survival was 57.4 for the immersion only treatment, 50.3 for the oral only treatment, and 53.5 for the combination immersion and oral treatment. In 1989-1990, no significant difference was found between vaccinated and non-vaccinated fish. However, in 1989-1990, a vaccine-oil emulsion was topcoated on a floating feed, rather than incorporating vaccine in a sinking pellet. In 1990-1991, overall mortality in vaccinated fish was significantly less (P < 0.05) than non-vaccinated fish, with 41.2% mortality in vaccinates compared to 63.5% in non-vaccinated fish, for an RPS of 35.1. In examining RPS values for individual farms, two farms had excellent results, with RPS values of 81.3 and 76.9; two farms had only moderate success, with RPS values of 26.6 and 15.4; and one location had greater mortality in the vaccinated fish than in the non-vaccinated fish. However, that farm had only two ponds in the study and experienced significant losses to proliferative gill disease in the pond with vaccinated fish.     

蓄水塘养殖斑点叉尾鱼回成鱼试验

长江水产研究所试验场用于人工繁殖的蓄水塘,面积8亩.每年6月份以前用于鲤、鲫及四大家鱼的人工繁殖蓄水,2001年我们在人工繁殖过后,利用该池进行了斑点叉尾鱼回成鱼养殖试验,取得了明显的经济效益.现将其主要措施总结如下.     

Use of Channel Catfish,Ictalurus punctatus,Pituitary as a Spawning Aid: Influence of Seasons and Preparations on Efficacy

Channel catfish, Ictalurus punctatus, pituitary powder (CP) was prepared and administered to determine the effect of pituitary preparation, head selection criteria, and season of collection on the biological potency of this gonadotropic preparation. Pituitaries were harvested from three catfish processing plants throughout the months of December, February, March, and April to investigate the effect of season on CP potency. Gravid female channel catfish were injected intraperitoneally (IP) with priming (2 mg/kg) and resolving doses (8 mg/kg) of CP treatments, luteinizing hormone‐releasing hormone analog (LHRHa), or saline. Pharmaceutical grade Carbopol 971P resin (CAR) was tested as a 1% aqueous dispersion in physiological saline and administered with CP (10 mg/kg) as a IP single injection at a final volume of 2 mL per kg as a slow‐release vehicle. Individual females were hand‐stripped, and eggs were fertilized with freshly harvested blue catfish, Ictalurus furcatus, spermatozoa. Pituitaries processed with either acetone or ethanol/acetone resulted in significantly different ovulation rates of 35 and 73%, respectively (P≤ 0.01). Ovulation success was not significantly different among CP and LHRHa treatment groups. Ovulation rates were not significantly different among treatment groups of CP collected in April (74%) or December (67%), or collected from male (69%), or small individuals (55%). The shortest latency period among CP treatment was from CP collected in December and from males at 39.1 ± 0.7 and 38.5 ± 0.4 h, respectively. The CAR vehicle treatment performed poorly resulting in an average ovulation rate of 19.0%, with 3.3% viable embryos at 36 h post‐fertilization. Pituitaries collected from channel catfish potentially represent a viable spawning aid for the production of hybrid channel × blue catfish.