6种渔药对芝麻魽苗种的毒性试验研究

[目的]探索常用杀虫药物对芝麻魽的毒性。[方法]在水温为(20±1)℃的静水条件下,选择智水高铜、虫菌净、晶体敌百虫、福尔马林、辛硫磷、高锰酸钾6种常用渔药对芝麻魽苗种进行毒性试验。[结果]智水高铜、虫菌净、晶体敌百虫、福尔马林、辛硫磷和高锰酸钾对芝麻魽苗种的安全浓度分别为:0.24、0.35、0.26、0.42、0.02和0.18 mg/L。芝麻魽苗种对6种药物的敏感性大小顺序为:辛硫磷高锰酸钾智水高铜晶体敌百虫虫菌净福尔马林,说明芝麻魽苗种较家鱼对药物的敏感性更高。[结论]该研究可为今后芝麻魽的人工养殖提供用药参考。     

池养珠江斑鱯人工繁殖和胚胎发育的初步研究

对在养殖池塘中培育珠江斑鱯Mystus guttatus亲鱼和人工繁殖的主要方法进行了总结，并提出：斑鱯雌、雄亲鱼的外观特征可作为鉴别其性成熟度的依据；对斑鱯雌鱼进行人工催产时宜分2次注射（间隔时间为24h），第1针注射PG（鲤）＋LRH-A＋DOM，第2针注射LRH-A＋DOM＋HCG。对斑鱯进行人工授精后，在水温27．5℃的条件下，受精卵约经17h 30min进入原肠期，胚胎孵化时间约为55h。     

Stocking density effects on growth and production of the threatened silurid catfish,Mystus cavasius (Hamilton) fingerlings in nursery ponds

The fingerling‐rearing experiment of the threatened catfish, Mystus cavasius was carried out at different stocking densities in earthen nursery ponds. Twelve‐day‐old fry were stocked at 200 000 ha^?1 in treatment‐1 (T₁), 250 000 ha^?1 in treatment‐2 (T₂) and 300 000 ha^?1 in treatment‐3 (T₃) respectively. The mean length and weight of fry at stocking was 1.24 ± 0.25 cm and 0.11 ± 0.04 g respectively. Fry in all the experimental ponds were supplemented with SABINCO nursery feed for the first 14 days and starter‐I feed for days 15–56. The physico‐chemical parameters and plankton population of pond water were within the suitable level for fish culture. Growth in terms of final weight, final length, weight gain, length gain and specific growth rate and survival of fingerlings were significantly higher in T₁ than those in T₂ and T₃. Feed conversion rate was significantly lower in T₁ followed by T₂ and T₃ in that order. Significantly higher number of fingerlings was produced in T₃ than that in T₂ and T₁. Even then, consistently higher net benefits were obtained from T₁ than those from T₃ and T₂. Among the treatments evaluated, 200 000 fry ha^?1 was the best stocking density considering the highest growth, production and net benefits of fingerlings of M. cavasius in nursery ponds.     

The dietary protein requirement of a bagrid catfish, Mystus nemurus (Cuvier & Valenciennes), determined using semipurified diets of varying protein level

Triplicate groups of Mystus nemurus (Cuvier & Valenciennes) were fed isoenergetic semipurified diets containing seven dietary protein levels from 200 to 500 g kg^–1 diet for 10 weeks. Dietary protein was supplied by graded amounts of a protein mixture (tuna muscle meal:casein:gelatine) at a fixed ratio of 50:37.5:12.5. Mystus nemurus fingerlings of initial weight 7.6 ± 0.2 g were fed close to apparent satiation at 2.5% of their body weight per day in two equal feedings. Growth performance and feed utilization efficiency increased linearly with dietary protein level from 202 to 410 g kg^–1 diet and declined with protein levels of 471 g kg^–1 diet or above. Protein efficiency ratio and apparent net protein utilization started to decline when the fish were fed with dietary protein levels exceeding 471 g kg^–1 diet. Fish fed with lower protein diets (202–295 g kg^–1 diet) had significantly ( P  < 0.05) higher carcass lipid content compared with fish fed with higher protein diets. Carcass lipid contents were inversely related to moisture content. Dietary protein did not significantly affect fish carcass protein and ash content. Using two-slope broken-line analysis, the dietary protein requirement for M. nemurus based on percentage weight gain was estimated to be 440 g kg^–1 diet with a protein to energy ratio of 20 mg protein kJ^–1 gross energy. This level of protein in the diet is recommended for maximum growth of M. nemurus fingerlings weighing between 7 and 18 g under the experimental conditions used in this study.     

野生斑(鱼蒦)人工繁殖试验

2005年和2006年共进行了12尾野生斑鳠人工繁殖试验,采用2次注射催产素的方法,4次催产成功,成功率67%,效应时间18~23 h,平均受精率51.25%,平均孵化率32.5%。试验发现,斑鳠卵粘性较好,孵化率受水温影响较大,25℃左右影响较为明显,保持在26℃以上较好。     

丝尾鳠的驯养及人工繁殖研究

丝尾鳠（Mystus wyckioides）是分布于云南省境内澜沧江水系的土著鱼类。2005年起,云南省渔业科学研究院和景洪市水产研究所共同在澜沧江的一级支流中采集野生亲本,并进行了驯养及人工繁殖研究。于2006年4月首次获得人工繁殖成功,至2009年已累计繁殖成功并培育出5cm以上苗种70余万尾。经过4年的技术改进,2009年催产6批、28组,催产率达到100%;授精率达到71%;孵化率达到88%。     

长江大鳍鱯的人工繁殖

本文对长江大鳍亲鱼的池塘培育和人工繁殖技术进行了研究。１９９２年～１９９４年期间,采用池塘混养技术,将长江野生大鳍引入池塘进行驯化和培育,连续２年获得成熟亲鱼并进行人工繁殖。在池塘环境中,大鳍雌亲鱼成熟率分别为８１８％和７０６％,雄亲鱼分别为１００％和９３５％。采用多种催产药物混合注射的催产方法,可以得到较好的催产率。大鳍人工繁殖适宜的催产剂量是雌鱼每ｇ体重注射ＬＲＨ－Ａ０３～０５μｇ、ＤＯＭ００３～００５ｍｇ和ＨＣＧ５～１０ＩＵ,雄鱼减半或同量。水温２４～２６℃时,催产效应时间为１２～１３ｈ。受精卵在水温２７～２９℃时需５３～５５ｈ孵化出膜。大鳍人工繁殖受精率不高与其雄鱼精巢特殊的组织结构有关。     

Improved survival and growth performances with stocking density manipulation and shelter availability in bagrid catfish Mystus nemurus (Cuvier & Valenciennes 1840) larvae

Manipulation of stocking densities (10, 20, 30, 40 and 50 larvae L^?1), each with or without the presence of shelter was conducted to determine the effects on survival, cannibalism and growth performances of larval bagrid catfish Mystus nemurus (Valenciennes 1840) from 2 to 14 days after hatching. This study revealed that stocking density significantly affected survival, cannibalism, total length, feed intake, specific growth rate and final weight of bagrid catfish larvae. Significantly higher survival was observed at moderate stocking density of more than 20 but less than 50 larvae L^?1. Survival was significantly low beyond this threshold and was the lowest at 10 larvae L^?1, coincides with the highest cannibalism. Total length, feed intake, specific growth rate and final weight were significantly higher at 10 larvae L^?1. Shelter significantly improved total length and feed intake. No significant effects of stocking density and shelter were observed on the apparent feed conversion ratio and coefficient of variation. There was also no significant interaction between stocking density and shelter in all parameters. This study suggests that bagrid catfish larvae could be cultured at more than 20 but less than 50 larvae L^?1 with the availability of shelter for optimal larviculture condition.     

池塘主养白须公试验

在0.27 hm2土池进行了主养红白须公秋片鱼种试验,放养红白须公夏花33855尾,白鲢夏花6000尾,花鲢夏花2000尾。经97 d饲养,出塘红白须公秋片17360尾,1675.24 kg,平均体重96.5 g,成活率51.2%,花、白鲢秋片580 kg,平均产鱼8457.15 kg/hm2,其中红白须公占77.3%,产值达108 750元/hm2。     

野生与养殖斑鱯肌肉营养成分的比较分析

为比较野生与养殖斑鱯(Mystus guttatus)肌肉生化组成的差异,采用常规方法对野生与养殖斑鱯肌肉的一般营养成分、氨基酸组成及脂肪酸组成进行测定。结果表明,野生斑鱯肌肉中粗蛋白含量显著高于养殖斑鱯(P0.05),粗脂肪含量显著低于养殖斑鱯(P0.05)。野生与养殖斑鱯肌肉中均检测到17种氨基酸,各种氨基酸的含量在野生与养殖斑鱯间无显著性差异(P0.05),但野生斑鱯肌肉必需氨基酸总量(7.20%)显著高于养殖斑鱯(5.86%)(P0.05)。野生和养殖斑鱯群体的氨基酸营养价值差别不大,且必需氨基酸含量符合WHO/FAO和鸡蛋蛋白标准模式。野生和养殖斑鱯肌肉中均检出16种脂肪酸,其中野生斑鱯肌肉中检出C15∶0和C20∶3n6而未检出C20∶0和C22∶6n3,而养殖斑鱯肌肉中检出C20∶0和C22∶6n3而未检出C15∶0和C20∶3n6。将野生斑鱯肌肉中的各种脂肪酸含量与养殖斑鱯相比较,发现除C20∶0、C20∶3n6、C15∶0和C22∶6n3外,其他各种脂肪酸含量在两种群体之间无显著差异(P0.05)。野生斑鱯肌肉中的C22∶6n3含量为0,显著低于养殖斑鱯(1.16%)(P0.05)。大类脂肪酸中,野生斑鱯的∑PUFA及∑n-6PUFA均显著高于养殖斑鱯(P0.05)。