【作者】 石振广；

【导师】 董双林；

【作者基本信息】 中国海洋大学 ， 水产养殖， 2008， 博士

【摘要】 1.达氏鳇隶属于硬骨鱼纲(Osteichthyes),辐鳍亚纲(Actinopterygii),软骨硬鳞总目(Chondrostei),鲟形目(Acipenseriformes),鲟科(Acipenseridae),鳇属。鳇属仅有两个种,其一是著名的欧洲鳇,鱼子酱售价高达$10000/kg,分布于黑海里海和咸海流域,据记载欧洲鳇最大个体长6米,体重3200千克(Berg,1948);其二就是分布于黑龙江的达氏鰉,达氏鰉体长可达5.6米,体重达到1000千克(Mikhail L.et al,1997)。达氏鳇是黑龙江特产鱼类,为珍稀种类。其肉味鲜美,营养丰富,其“鱼子酱”,为上等佳肴,被誉为“黑色黄金”,达氏鳇经济价值极高,现在产地鱼体售价140元/kg左右,鲜冻脊索每千克售价400元,鱼胃价格200元/kg,鱼皮也是上等制革原料。其鱼子酱国内售价5000元/kg左右。达氏鳇为凶猛的肉食性鱼类,耐低温,一年四季在自然界均摄食生长,生长适宜温度为15～22℃。达氏鳇性成熟晚,生殖周期长,雌鱼初始成熟年龄16～20年,雄鱼为12年以上,繁殖水温12～21℃。就自然水域种群的数量而言,达氏鳇已经成为濒危物种,其自然资源已遭到严重的破坏。主要是人为酷捕、兴修水利(兴建大坝)和环境污染所致。2.在2001-2002年5-6月对黑龙江中下游江段捕捞的达氏鳇亲鱼进行严格地挑选、运输、蓄养,经过催产试验发现,雄性亲鱼对HCG、HCG+鲤脑垂体没反应,而注射LRH-A、LRH-A+鲤脑垂体催产效果良好,且两者间没有明显差异,因此,LRH-A是达氏鳇催产的理想药物。进一步试验发现,达氏鳇对催产药物剂量的要求并不十分严格,催产剂量在2-12μg /kg时对受精、孵化率和仔鱼成活率没有很大的影响,催产药物剂量达14-20μg /kg时,达氏鳇卵的受精率、孵化率没有明显的影响,但对仔鱼的成活率的影响显著。本文对“杀鱼”取卵法、活体取卵法和多次挤压采卵法的采卵率、卵的质量以及受精率、孵化率和亲鱼存活率指标进行比较发现,只有活体取卵法既能使亲鱼存活80%,又能使受精率和孵化率分别达到88%和82%,与目前生产上普遍采用的“杀鱼”取卵法的效果相近,而多次挤压取卵法劳动强度大,受精率、孵化率及亲鱼存活率都较低,因此,采卵的最佳方法是活体取卵法。半干法的受精率为97%,孵化率95%,分别较干法的90%和85%高近十个百分点,因此达氏鳇的授精方法宜采用半干法。综合受精率、孵化率、脱黏效果、水霉菌感染情况及劳动强度、生产成本的分析,最为理想的脱黏法为滑石粉法。用改进尤先科式孵化器孵化达氏鳇受精卵,其孵化的适宜水温为16-24℃,最佳水温为20℃。3.对不同形状的玻璃钢、水泥培育池对达氏鳇前期仔鱼成活率的影响进行了初步研究发现,圆形较方形池、玻璃钢的较水泥池培育的成活率高。同时对培育温度试验设计10个处理,即8、10、12、14、16、18、20、22、24、26℃,结果表明培育达氏鳇前期仔鱼的适宜水温为14-24℃,最佳水温为18-22℃。4.培育达氏鳇仔鱼的关键是如何将内源性营养安全地过渡到混合营养,再由混合性营养过渡到外源性营养,即仔鱼开口的过程。本试验用鲜鱼肉自制的开口料,熟鸡蛋黄、鲑鱼开口料、活轮虫、枝角类、水蚯蚓、卤虫幼体分别进行开口试验,通过对体长、体重的生长及成活率指标的比较发现,培育达氏鳇仔鱼最理想的开口料是卤虫幼体和枝角类,其次是水丝蚓和熟鸡蛋黄,较差的为轮虫,最差的是鲑鱼开口料和鲜鱼肉自制的开口料。5.用全价人工配合饲料进行驯化转口是稚鱼培育的关键,也是达氏鳇商品养殖的关键。本试验对水丝蚓、卤虫幼体、枝角类培育开口的达氏鳇稚鱼,分别用颗粒饲料、颗粒料+水丝蚓、+枝角类、+卤虫幼体和颗粒饲料浸水丝蚓浆、枝角类浆、卤虫幼体浆汁进行驯化转口,试验表明:用卤虫幼体、枝角类培育开口的达氏鳇稚鱼较用水丝蚓培育开口的转口时间短,驯化成功率高、成活率及生长率均较水丝蚓的高,用浆汁浸泡颗粒料进行驯化较先喂颗粒料后喂水丝蚓、卤虫幼体、枝角类(即颗粒料+水丝蚓、+枝角类、+卤虫幼体)的转口时间短、稚鱼成活率高,生长速度快,驯化成功率高。因此,用枝角类,卤虫幼体浆汁浸颗粒饲料进行驯化是行之有效的。6.养殖试验设计流水水泥池、网箱、土池塘三个处理,每个处理有一个重复。结果表明流水水泥池效果最好,其次是网箱,最差的是土池。水泥池、网箱养殖的体重分别达到45.96kg和44.87kg,而土池的只长到37.9kg,明显较流水池和网箱养殖生长速度慢。网箱养殖的饵料系数为1.2,高于流水池的1.0,而低于土池的1.4。7通过连续递增盐度和阶段性递增盐度对史氏鲟、达氏鳇和杂交鲟(达氏鳇♀×史氏鲟♂)三种鲟鱼进行盐度驯化试验,结果表明:采用阶段性递增盐度对史氏鲟、达氏鳇和杂交鲟进行驯化,最终达到盐度30‰时死亡率分别为6.7%、3.3%和5.0%,因此,鲟鱼海水驯化养殖是现实可行的。8.人工养殖条件下,对达氏鳇杂交种[达氏鳇♂×天然杂交种♀(达氏鳇♀×史氏鲟♂)]的生长特性进行了初步研究,结果表明:平均全长为33.32cm、平均体重为145.83g的139日龄幼鱼经75d的人工饲养长成平均全长为48.79cm、平均体重为437.36g的个体,全长与日龄之间呈线性关系L=0.2195t+3.2969,R2=0.9594,其全长日均增长量为2.06mm、平均瞬时增长率为0.0763,体重与日龄呈指数函数关系,Wgc=17.216e0.0516t,R2=0.956;体重日均增长量为3.8871g、平均瞬时生长率为0.2197;体重与全长的回归曲线为WwL=0.0056L2.8929,R2=0.9982,幂指数接近于3,表明该鱼体重与全长的立方呈正相关系,属于等比生长类型。更多还原

【Abstract】 1. Kaluga Huso dauricus belongs to Huso genus, Acipenseridae, Acipenseriformes, Chondrostei, Actinopterygii, Osteichthyes. There are only two species in genus Huso, which one is famous beluga Huso huso living in Black, Azov and Caspia Seas, that its caviar cost $10000/kg. The other one is Kaluga which is the largest freshwater fish in Amur river system reaching more than 5.6 m in length and more than 1000 kg in weight.Kaluga is endemic and rare species, its flesh is delicious and rich in nutrition. Its caviar is called as“black golden”and super dishes, costs RMB5000/kg at home. Kaluga price is high at RMB140/kg body, and RMB200/kg stomach, RMB 400/kg nerve cord. Kaluga skin is super leather materials.Kaluga is piscivorous and matured later, long reproductive cycle. Males population spawn for the first time at age 12～14 years, and females, at age 17–23. Spawning occurs in May–June at 12–21 ?C in Amur Rivers, in calm waters.As to the number of wild population, Kaluga is endangered species and its natural resource was decreased. This decline resulted from overfishing and environmental degradation such as: accumulation of pollutants in sediments, damming of rivers.2. Strict selection, transportation and maintenance of Kaluga bloodstocks were carried out from Amur down-midlle stream during May and June in 2001 and 2002. Male Kaluga breeder were not correspondent to HCG, HCG + carp PG, carp PG but LRH-A, LRH-A+ carp PG in effect and no different through inducing experiment, which show that LRH-A may be ideal hormone for inducing. In further investigation, through analysising of fertilization rate, hatchery ratio and larvae survival ratio, It was shown that wild-caught Kaluga broodstock is not rigid to inducing dose of LRH-A. It does almost not influence on fertilization, hatchery rate and larvae survival ratio that the dose vary between 2-12μg /kg BW, but dosage is 14-20μg /kg BW there is only an impact on the survival ratio of larvae kaluga. Through comparing the ratio of eggs harvested, the quality of eggs, fecundation rate (FR),hatchery ratio(HR) and viability of breeder kaluga came from“killed breeder”, biopsy and“multi-stroke”, It was found the effect of Biopsy similar with“killed breeder”populating in lot that only biopsy can save breeder 80% up and keep fertilization rate(FR) and incubation ratio reaching separately 88% and 82% while FR and HR are lower of“multi-stroke”but labor intention is high. Biopsy is the best way for eggs harvested. Fertilization methods were compared, which is shown that FR and HR are respectively 97% and 95% of“half-dry”more 10% than 90% and 85% of“dry methods”so that insemination of Kaluga should be“half-dry”.“talcum powder”is the best ideal to removing stickiness from eggs through comprehensive analysis of FR and HR, the effect of removal stickiness , infection of Saprolegnia and labor intensity.It was found that favorable and optimal temperature is 16-24°C and 20°C respectively for incubation of Kaluga eggs fertilized through comparison of hatchery rate, the ratio of healthy larvae, infection rate of Saprolegnia by Yuschenko incubators improved.3. A preliminary study was carried out on the influence of different tank shape made from fiberglass and concrete on survival ratio of prelarvae Kaluga. It was discovered that survival ratio is more high of round tank than rectangular one,fiberglass tank than concrete one. While the experiment was designed according to the culture temperature of Kaluga prelarvae of 10 treatments, which were 8, 10, 12, 14, 16, 18, 20, 22, 24, 26°C. Results showed that favorable and optimal temperatures are 14-24℃ and 18-22℃respectively.4. The key of larvae Kaluga culture is how to transfer the larvae from the endo- nutrition (endogenous feeding phase or yolk-sac nutrition) to mix-nutrition, then from mix-nutrition to exogenous feeding, which is called as initial feeding. Initial feeding trials were supplied with fresh fish mince self-made, boiled egg yolk of chicken,salmon starter,alive rotifer, cladocera, tubifex, artemia nauplii. Being comparison of body length (BL), body weight (BW) growth and survival ratio, it was found that the best ideal starter is artemia nauplii and Cladocera, next is Tubifex and boiled egg yolk of chicken, inferor is salmon starter and fresh fish mince self-made.5. Weaning Kaluga is the key to rear Juvenile and table fish with pellet food. Trials were conducted of weaning juvenile Kaluga were initiated to feed tubifex, artemia nauplii, cladocera,which juvenile were feeding with pellet food (PF) , PF+ tubifex, PF+ artemia nauplii, PF+ cladocera, and PF dipped in tubifex ,artemia nauplii,cladocera juice. Results show that Juvenile Kaluga were weaned successfully initiated to feed artemia nauplii and cladocera in shorter time, higher weaning percent, higher survival ratio and growth rate than tubifex, that with pellet food dipped in juice of tubifex, artemia nauplii, cladocera in shorter time, higher weaning percent, higher survival ratio and growth rate than first with formulated food then tubifex, artemia nauplii, cladocera, therefore it is effective that Kaluga juvenile is weaned by pellet food dipped in cladocera and artemia nauplii juice.6. Trials were designed thee treatments with repetition in concrete tanks with flowing water, net cages and earth ponds. Results indicate farming effect in order is concrete tanks with flowing water, net cages and earth ponds, that body weight reach at. 45.96kg, 44.87kg and 37.9kg respectively, and that food coefficient is as following: 1.0, 1.2, 1.4 in five years later. 7. A preliminary study on acclimation of Kaluga sturgeon, Amur sturgeon and the hybrid to saline water.A preliminary study has been carried out on the acclimation of Kaluga sturgeon (Huso dauricus), Amur sturgeon (Acipenser schrenckii) and the hybrid (H.dauricus♀×A.schrenckii♂) to saline water by increasing salinity continuously and continually. The cumulative mortality are 23.3%, 65% and 33.3%, and 3.3%, 6.7% and 5.0% separately of Kaluga sturgeon, Amur sturgeon and the hybrid sturgeon in continuous Increasing salinity experiments and in continual increasing experiments until the salinity reaches at 30‰at last. The possibility of sea farming and the principle of acclimation were discussed.8. A preliminary study on juvenile growth performance of Kaluga (Huso dauricus ) hybrid under artificial farming conditions. Under artificial farming conditions, a preliminary study was carried out on juvenile growth characteristics of Kaluga hybrid {[(Kaluga♀×Amur sturgeon♂) natural hybrid♀]×Kaluga♂}. The results showed that the juveniles reached a mean body weight (MBW) of 437.36g and a mean body total length (BTL) of 48.76 cm after 75 days rearing from a mean body weight of 145.83g and a mean body total length 33.32 cm when they were 139 days old. We found that there is a linear relationship between total length and days old in the form of L=0.2195t+3.2969, R2=0.9594, and there is power functional relationship Wgc=17.216e0.0516t, R2=0.956, between body weight and days old, and the total length-weight relationship is WwL=0.0056L2.8929, R2=0.9982. The function is close to 3, which shows that the weight is related to the cube of the length and the growth is isometric of hybrid juveniles. The body total length increased at 2.06mm on average of hybrid juveniles and instantaneous growth ratio was 0.0763, and the body weight gained at 3.8871g/d on average and instantaneous growth ratio is 0.2197.更多还原