斑点叉尾苗种全长与体重的关系

本文运用生物学统计方法对2700尾斑点叉尾鮰苗种全长与体重的关系进行了研究。结果表明,在本试验条件下,斑点叉尾苗种全长主要集中在15.5～17.5cm,体重主要集中在20～35g;体重与全长之间存在极显著相关关系;体重与全长之间的关系主要表现为幂函数关系,其关系式为Y=0.009X2.933。     

池塘培育斑点叉尾鮰苗种技术

斑点叉尾 鱼回 亦称沟鲶 ,属鲶形目 鱼回 科鱼类 ,是美国主要淡水养殖鱼类 ;该鱼具有适应范围广、食性杂、个体大、生长快 ,抗病能力强 ,肉质细嫩鲜美等优点。为了提高该鱼在北方池塘养殖产量 ,我们 1998年做了斑点叉尾鱼回 池塘苗种培育试验。1　材料与方法1 1　池塘条件本实验选在吉林农大水库渔场池塘 ;池塘面积 2 0亩 (斑点叉尾 鱼回 苗种培育池面积过大 ,不利于驯化饲养 ) ,养殖期间平均水深 1 5ｍ左右 ,池塘底泥在 2 0～ 30ｃｍ之间 ,注排水方便 ,水量充足 ,水质良好。 6月 18日全池用生石灰 2 6 0ｋｇ遍洒 ,6月 2 0日用网拉池底 …     

国外简讯

美国筛选生长快的斑点叉尾鱼回品系　　美国７０年代初开始进行斑点叉尾鱼回的遗传和繁殖研究，但这一研究对斑点叉尾鱼回的商业化生产无显著影响。为筛选生长快的斑点叉尾鱼回，对美国农业部鲇鱼遗传研究所所选育的红河品系ＵＳＤＡ１０２、德克萨斯品系的ＵＳＤＡ１０３和密西西比三角洲的普通品系Ｍｎ进行了生长对比试验。分别投喂含粗蛋白２５％、３５％和４５％的饲料，能量蛋白比分别为１０．０、８．１和６．８千卡／ｇ，鱼体重１５．５ｇ。日投饵２次，试验８周。发现ＵＳＤＡ１０３品系摄食量大、增重快且饲料转换率好，Ｍｎ品系最…     

斑点叉尾人工繁殖技术总结

斑点叉尾鲴俗称沟鲶、河鲶、美洲鲶，原产于美洲，1984年湖北省率先从美国引种，经20多年的试验、推广、养殖，今已成为我国淡水鱼类引种、养殖和加工出口最成功的品种之一。2007年福建省海洋与渔业局将斑点叉尾鲴的人工苗种繁育工作列为2007年度重点项目，由福建省淡水研究所和建瓯市鱼种场共同承担。2007年初在建瓯市鱼种场引进美国斑点叉尾鲴原种亲鱼1200尾，雌鱼平均体重2．15kg，雄鱼平均体重2．25kg，年龄4龄。经一年多培育，2008年4月下旬开始产卵，6月下旬产卵结束，人工孵化也于7月初结束。由于斑点叉尾鲫具有特殊的繁殖习性，因此它的繁殖方法与其他鱼类有较大的不同。现结合生产实践将有关技术总结如下。     

池塘培育斑点叉尾苗种技术

斑点叉尾鱼回(Ictaluruspunctatus),亦称沟鲶,属鲶形目鱼回科鱼类,具有食性杂,生长速度快,产量高,易起捕,抗病力强,肉质细嫩等特点。近年来,斑点叉尾鱼回的成鱼养殖发展迅速,规模不断扩大,苗种需求不断增加,为了进一步适应市场需求和提高养殖效益,笔者于2002年进行了池塘高效培育斑点叉尾鱼回苗种试验,取得了较好的经济效益。现将苗种培育技术总结如下。1材料和方法1.1池塘条件及清整试验塘为桂林市水产研究所九美桥基地1#、2#塘,其中,1#塘2534m2、2#塘2400m2。池底平坦,保水性较好,平均水深1.2m。无污染源流入,池塘用水主要为天然雨水。鱼…     

斑点叉尾鮰亲鱼培育和繁殖期管理应掌握的技术环节

斑点叉尾鱼回又称沟鲶、美洲鲶,生长速度快,适温范围广,无鳞、无肌间刺,鱼肉含水率低,是适宜于养殖和加工的优质淡水品种。为使其养殖与加工得到快速发展,首先要解决苗种问题,因此,斑点叉尾鱼回的批量繁殖显得尤为重要。通过几年来的摸索,笔者认为要从以下6个方面的技术问题入手,可以保证苗种生产的持续、稳定发展。一、必须保持一定规模的亲鱼种群斑点又尾鱼回卵粒大,且怀卵量少,4龄亲鱼怀卵量仅1.5万粒左右,每公斤亲鱼怀卵量约4000粒,是“四大家鱼”平均怀卵量的1/35左右。由于斑点叉尾鱼回的生物学特性,加之繁殖期间的不稳定性因素,影响…     

斑点叉尾“传染性套肠症”的诊治

斑点叉尾鱼回“传染性套肠症”是近年来在我国发生的一种斑点叉尾鱼回的新型细菌性传染病,危害很大,已经连续几年造成了大批的斑点叉尾鱼回发病死亡,严重地威胁着斑点叉尾鱼回养殖业的健康发展。目前初步认为该病是由嗜麦芽寡养单胞菌(Stenotrophomonasmaltophilia)引起的斑点叉尾鱼回的急性致死性传染病,以发生严重的肠炎、肠套叠和脱肛为特征,在短时间内即可引起大批的斑点叉尾死亡,我们称此病为“斑点鱼回叉尾鱼回传染性套肠症(InfectiousintussusceptionofchannelcatfishIICC)”。由于该病具发病突然,来势凶猛,传染快,呈流行性,死亡…     

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。     

斑点叉尾鮰腐皮病的治疗

斑点叉尾鱼回是我国重点推广的名特优水产养殖品种之一,它原产于北美洲。在美国的淡水养殖中占主要地位,我国于1984年从美国引种获得成功。其具有广温性、杂食性、产量高、抗病力较强等优点,受到养殖户的欢迎。但在早春对斑点叉尾鱼回鱼种进行分规格饲养时,如预防措施不当或操作不仔细,极易造成其发生腐皮病并大量死亡。现将2003年3月的一例斑点叉尾鱼回腐皮病诊治情况介绍如下。1　发病情况某养殖场2001年7月至9月从四川省成都购进斑点叉尾鱼回鱼种,2002年3月初越冬结束,苗种生长正常,最大个体达300g/尾,一般在100g/尾左右,成活率在90%…     

美国筛选出优质斑点叉尾鮰新品系

密西西比大学水产养殖中心的科研人员将筛选出来的斑点叉尾鱼回ＵＳＤＡ 10 3品系与当地品系的斑点叉尾鱼回进行了生长、饲料效率、鱼片产量以及肉质比较。所用饲料的蛋白质含量分别为 2 6%、2 8%和 3 2 %。试验鱼规格为 3 2 .5ｇ/尾和 47.3 ｇ/尾 ,分别放养到 2 4个 0 .0 4ｈｍ2 的土池中 ,密度 185 3 0尾 /ｈｍ2 。每天进行饱食投喂 1次 ,养殖 5～ 10个月。测定结果摄食这 3种饲料的ＵＳＤＡ10 3品系的斑点叉尾鱼回 ,其增重率和饲料利用率均高于密西西比品系的斑点叉尾鱼回。组织分析测出 ,ＵＳＤＡ10 3斑点叉尾鱼回内脏的脂肪含量低、鱼…     

南方大口鲶苗种培育影响因素初步分析

在１０个面积均为１５ｍ＾２的实验池中，分三批放养全长６－９ｍｍ的南方大口鲶鱼苗共４．１５２万尾，经４０－５０天培育，获全长６－８ｃｍ的鱼种２．３２５万尾，出池率５６％，还结合生产情况及室内实验结果，分析了水温、放养密度及饵料对苗种成活和生长的影响，拟合了苗种体重与全长，日龄与全长及日均增长率的回归关系。     

Evaluation of Decapsulated Artemia Cysts in Hatchery Diets for Channel Catfish Ictalurus punctatus Fry and Effects on Subsequent Fingerling Production

Abstract.— Two 10-d hatchery growth trials were conducted to determine if differences in growth, body composition, and survival existed among catfish fry Ictalurus punctatus fed a diet of 100% catfish-starter (CS) or CS in combination with decapsulated Artemia cysts (DAC) at 25%, 50 % , or 75% of diet weight. A 120–d production trial was undertaken immediately following the first hatchery trial to evaluate the effects of diet on production characteristics (survival, length, weight, feed conversion ratio, and total yield) of fingerling catfish produced from hatchery-raised fry. Fry fed diets containing DAC weighed 61–98% more ( P < 0.05) than fry fed only CS. The size differential of DAC-fed fry was maintained through 120 d of growth in simulated nursery ponds (0.001-ha earthen-bottom pools). The increased growth of fry fed DAC might have been related to differences in dietary lipid content, amino acid composition, or digestibility of CS and DAC. Body weights of fingerlings produced under simulated production conditions from fry fed hatchery diets containing 50% and 75% DAC were 17% and 25% higher, respectively, 130 d post-hatch, than fingerlings produced from fry fed only CS. In addition, the total yield of fingerlings produced from fry fed 75% DAC was 17% greater that that of fingerlings produced from fry fed only CS. The increased performance of fingerlings produced from DAC-fed fry could have resulted from their larger size at stocking, since larger fry might be capable of capturing natural food organisms and ingesting prepared diets more effectively than smaller fish. CS-DAC diet combinations could be used to increase weight gain of hatchery-raised fry if the cost-benefit ratio of adding DAC to the standard hatchery diet warrants its use.     

Evaluation of a Mechanical Grader to Separate Fingerling Channel Catfish,Ictalurus punctatus,into Length Groups

A Fischtechnik fingerling grader and bioscanner counter were evaluated for speed and accuracy in grading and counting channel catfish, "Ictalurus punctatus," fingerlings. Channel catfish fingerlings ranging in total length from 90 to 280 mm were graded into 110- to 140-mm, 140- to 170-mm, 170- to 200-mm and >200-mm length groups and counted. A sample of the fingerlings was manually separated through grader boxes with 109 mm (7/16 inch), 141 mm (9/16 inch) and 172 mm (11/16 inch) bar spaces to compare length variation within size groups with the mechanical grader. The accuracy of the bioscanner counter was tested by comparison with hand countintg. Fingerlings weighing 679 kg were mechanically graded and counted in 56 minutes, a rate of 12.1 kg/minute. Standard deviation for length within size groups was 10.9, 13.5, and 24.0 mm for the 109-mm, 141-mm, and 172-mm grader boxes, respectively; and 13.4, 12.6, 13.0, and 16.4 mm for the 110- to 140-mm, 140- to 170-mm, 170- to 200-mm and >200-mm mechanical grader length categories, respectively. Length variance within size groups was statistically lower for the mechanical grader compared with the box graders (P < 0.05). The bioscanner counter averaged a 5% overcount of channel catfish fingerlings compared with the manual count (P < 0.05).     

Growth performance of fingerlings in pen culture

Abstract. Studies were conducted on the growth performance and development of one-year-old fingerlings of seven species in lake pen culture. It was found that the body weight and length of the fingerlings increased evenly with each passing month. Based on the increase of length, these 7 species could be categorized into two groups; while based on body weight gain, they could be categorized into three groups. The growth Index of power functional relations concerning the weight and length ranged between 2·8 and 4·0, indicating that the two growths were in parallelism. It was considered that the condition factors should be calculated with b -value according to the differences of fish species and ages (month). The monthly average indexes of the length and weight increases of the seven species were calculated.     

Effects of several factors on growth of milkfish (Chanos chanos Forskal) fingerlings reared with artificial diets in aquaria

This paper presents the effects of feeding level, feeding frequency, salinity of water, kind and particle size of diets, and stocking density on the growth of milkfish (Chanos chanos Forskal) fingerlings which were reared with artificial diets in laboratory tanks. Experimental groups were designed using orthogonal array L₈, and the results were evaluated statistically. Growth of the milkfish fingerlings varied markedly with the kind of diets used and feeding level. The feeding frequency and particle size of the diets also affected growth of the fingerlings significantly, but the salinity of the water did not. The weight gain of the fingerlings did not vary with the stocking densities significantly, whereas the increase (%) in body length was greater at a lower stocking density. The milkfish fingerlings showed the best growth in terms of both weight gain and increase in body length when reared on a purified diet containing 35% casein and 15% gelatin as protein sources under the following conditions: feeding level, 30–35% of body weight; feeding frequency, twice a day; particle size of diets, 125–250 μm diameter; and stocking density, $\text{5 fish}\text{5-liter}$ tank. The means and confidence limits of the weight gain (%) and increase (%) in body length of milkfish fingerlings under the best conditions adopted were estimated to be 360 ± 63.7 and 62.1 ± 10.6, respectively.     

The Effect of Varying Biomass of Carryover Fish in Multiple‐batch Catfish,Ictalurus punctatus,Pond Production

The presence of carryover (fish >350 g stocked the previous year but not yet market size) channel catfish, Ictalurus punctatus, in multiple‐batch production ponds has been shown to affect overall production performance and costs. However, little attention has been paid to effects of varying biomasses of carryover fish in ponds. Twelve 0.1‐ha earthen ponds were stocked March 20, 2007, with 15,000 catfish fingerlings per ha (mean weight 31 g), and carryover fish at either 726, 1460, or 2187 kg/ha (mean weight 408 g, range 204–703 g) to compare the effect of three different biomasses of carryover catfish on the production performance of understocked fingerlings. Gross and net yields increased with increasing biomass of carryover fish. Growth and mean weight at harvest of fingerlings were significantly greater at the lowest biomass of carryover fish (<1460 kg/ha), but there was no difference between the medium and high carryover density treatments. Net returns were highest with the highest biomass of carryover fish, but fell by $688/ha in Year 2 because of slower growth of fingerlings in Year 1.     

东海细点圆趾蟹的生物学特性

根据1998—2000年在东海虾蟹资源调查和渔业生产监测调查中周年采集的1576只细点圆趾蟹样品，开展了基础生物学研究，结果表明，东海细点圆趾蟹的渔获群体甲长分布范围为26～95mm，甲宽为32～120mm，体重为5～410g，雄蟹个体平均大于雌蟹；春季雌蟹生长不明显，而雄蟹则生长迅速，2—6月平均增长率达38．7％；周年雌蟹略多于雄蟹，性比约为1：0．88，繁殖盛期为3—5月，不同个体怀卵量在6．8～75．8万粒之间，最小抱卵个体的甲长为46mm，甲宽为60mm，体重为59g，多数抱卵个体的甲长为50～60mm，甲宽为65～80mm，体重为80～115g。周年摄食强烈，半胃、饱胃率多数时间在50％～60％以上，其中冬春季摄食强度大于夏秋季．     

鲈种池塘越冬试验

１９９５年１１月至１９９６年５月，进行了较大规模的池塘鲈种自然越冬生产性试验，本文仅报告一口０．１３ｈｍ＾２微咸水池塘冬技术及效果，投入鲈种３０００尾，越冬后出池２１４０尾越冬成活率７１．３３％，平均全长和体重分别增加２．９ｃｍ和２９．７％，对池塘自然越冬与塑料大棚保温越冬进行了经济效益比较。     

夏牙鲆引进与室内池养成试验

2002年11月从美国引进夏牙鲆(Paralichthys dentatus)鱼苗2000尾,平均体长8．3 cm,平均体宽3．6 cm,平均体重8．26g,在室内长方形育苗池内试养,水温9-32℃,盐度20-28,通过投喂自制的湿颗粒饲料,控制水质,防治病害等措施,经过1年试养,夏牙鲆平均体长36．80 cm,体宽15．77 cm,体重达750 g。本试验为室内池养殖夏牙鲆提供了有实用价值的技术资料。     

4月龄泥鳅形态性状对体重的影响分析

随机选取305尾不同家系的4月龄泥鳅（Misgurnus anguillicaudatus）,测量其体重、全长、体长、头长、体高、尾柄高、尾柄长和体厚共8个性状指标。采用相关分析和通径分析方法,分别计算泥鳅各形态性状对体重的相关系数、通径系数和决定系数,揭示影响4月龄泥鳅体重的主要形态性状。结果表明,各形态性状与体重的相关系数均达到极显著水平（P〈0.01）。全长、体高、头长是直接影响体重的重要指标;其中,全长对体重的直接影响最大（0.548）,对体重的决定程度最高（0.3003）,其他性状对体重的直接作用较小,主要通过全长间接地影响体重。通过逐步多元回归分析,经偏回归系数显著性检验,以全长（X1）、头长（X2）、体高（X3）、尾柄高（X4）和尾柄长（X5）建立最优多元回归方程为Y=-4.515＋0.255X1＋1.744X2＋1.966X3＋1.422X4＋0.511X5。在泥鳅选育实际操作中,可以通过该方程对泥鳅体重进行预测和控制,主要用泥鳅全长指标进行选择,以达到间接选育体重、优化其生长性能的目的。