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1.
用放在海水池塘中的8个陆基围隔(50m×50m×18m),研究中国对虾(Penaeuschinensis)与不同密度海湾扇贝(Argopecteniradians)投饵混养的放养方式、生产力和极限放养量。对虾体长(285±016)cm,扇贝壳长(110±012)cm,放养密度分别为60尾/m2和0,15,45,75粒/m2,用投饵和施肥(鸡粪和化肥)饲养。结果表明,扇贝密度为0和15粒/m2时,对虾的成活率无显著差异。混养(扇贝15粒/m2)时对虾的出塘体长、体重和产量分别比单养高25%,38%和65%;当扇贝密度高于15粒/m2时,对虾的平均体长、体重和产量随扇贝密度的增加而显著减少(P<005)。扇贝密度为15和75粒/m2时,其产量由470kg/hm2增至1236kg/hm2;当扇贝密度高时,去壳后湿重占体重的百分数从(4284±344)%降至(3788±426)%。扇贝的极限放养量为600~800kg/hm2,适宜放养密度为10~15粒/m2。  相似文献   

2.
柳富荣 《内陆水产》2000,25(8):11-12
1999年5月~2000年4月,对垸内胜利湖和垸外新河的8只网箱养殖加州鲈效果进行了比较。结果表明,外河4只网箱养殖加州鲈平均净单产28.9~30.5kg/m^2,成活率86.0%~91.2%,增重倍数14.5~19.0,依次比内湖4只网箱的净产量(22.4~24.7kg/m^2)、成活率(81.0%~85.6%)、增重倍数(12.0~15.2kg/m^2)分别高4.7~6.1km/m^2、4.0%~5.6%、2.4~3.8kg/m^2;此外,相同水域不同放养密度的产量、成活率、增重倍数也有明显差别。  相似文献   

3.
1.目前对虾主要的病毒性疾病有几种?如何进行防治? 当前对虾的主要病毒性疾病有“白斑病”及“桃拉症”,防治的方法为:①种苗须经过病毒检测确定无毒后,才能进入养殖环境;②投喂优质的全价饲料,并在饲料内添加0.2%“多糖”、0.1%“人参皂甙”及稳定型0.2%Vc;③每5~7天向养殖水体全池泼洒“溴氯海因”0.5~0.6ppm或“二溴海因”0.3ppm1次;④养殖季节内,每15天全池泼洒“季胺盐络合碘”1.5ppm;⑤经常在养殖水体内使用生物制剂,以保持水环境的稳定。 2.对虾附肢发红是何原因?如何进…  相似文献   

4.
用5种药物治疗剑尾鱼聚缩虫病试验,结果呋喃唑酮无效,硝酸亚汞(1. 25 ±0. 25) mg/L、硫酸铜酸亚铁(5:2)合剂(8.5±0.5)mg/L、甲醛(30±5)mg/L、孔雀石绿(0. 9 ± 0. 1) mg/L对聚缩虫杀死率均在 95%以上;治愈率依次为:(92.5 ± 2.5)%、100%、(87.5±2.5)%、(82.5±2.5)%;剑尾鱼对药物的敏感性强度为孔雀石绿>硝酸亚汞>硫酸铜合剂>甲醛,安全浓度依次为:0.32、0.48、4. 1、9.4 mg/L。表明治疗剑尾鱼聚缩虫病用硫酸铜合剂(8. 5 ± 0. 5) mg/L、甲醛(30 ± 5) mg/L浸泡效果好。  相似文献   

5.
中国对虾与罗非鱼施肥混养的基础研究↑(*)   总被引:3,自引:0,他引:3       下载免费PDF全文
用4个海水池塘陆基围隔(5m×5m),进行了封闭式施肥混养中国对虾(Penaeuschinensis)与台湾红罗非鱼(Oreochromismosambicus×O.niloticus)的基础研究。结果表明,在不同密度条件下,对虾成活率45.0%~86.7%(平均664.2%),产量为75.7~111.8kg/hm2(57d),生产力为0.19/m2·d。池塘对中国对虾的负荷力为170.0kg/hm2。其中某些围隔对虾死亡较多的原因是负荷量超过了负荷力,发生饵料缺乏和自残。在限定罗非鱼放养量(8×103尾/hm2)的条件下,鱼虾最适放养尾数配比为1∶3,中国对虾(体长5.55cm)的最适放养量为24×103尾/hm2左右。  相似文献   

6.
尼罗罗非鱼吉富品系养殖推广中试研究   总被引:14,自引:0,他引:14  
在山东青岛、浙江湖州和广东番禺等地选定32个养殖户进行吉富尼罗罗非鱼推广试验,分别以当地养的尼罗罗非鱼“78”品系、“88”吕系及尼奥发交钱赤对照,比较研究了各项养殖性能。(1)吉富鱼的绝对增重率分别比三种对照鱼快22.4%17.6%和26.0%;瞬时增重率分别比三种对照鱼快12.1%、9.5%和7.7%;差异都显著。(2)平均成活率分别比对照组高6.8%、6.2%和1.5%;但吉富品系同“88”  相似文献   

7.
研究了饲料中添加凹土(0.0%、0.5%、1.0%、2.0%、4.0%和8.0%)对凡纳滨对虾(1.04~1.06g)存活和生长的影响。实验在淮海工学院江苏省海洋生物技术重点建设实验室进行,凡纳滨对虾(Litopenaeusvannamei)幼虾购自海南某育苗场;实验采用单因子6水平设计,每个水族箱放养10尾对虾,每个水平设3个重复。实验前停食24h,称其初始体重。日投饵2次,过量投饵;投饵2.5h后从每个水族箱收集残饵、粪便和虾壳。实验周期30d。所得数据用单因素方差分析和Turkey′s多重比较进行处理。结果表明,饲料中添加凹土显著地影响对虾的特定生长率,而对存活率、摄食量、饲料系数和吸收效率的影响不显著;在2.0%凹土水平,凡纳滨对虾的特定生长率显著高于0.0%凹土水平,但与其它处理差异不显著;总的看来,2.0%凹土添加组对虾的饲料系数低于其它处理,而摄食量高于其它处理。  相似文献   

8.
pH和盐度对斑节对虾存活,生长和渗透调节能力的影响   总被引:1,自引:0,他引:1  
斑节对虾幼虾(平均体重4.2-5.5g)的pH低临界值使用盐酸醋化海水的静态生物测定的方法来求得。在盐度32ppt进其致死pH(即96hLC50的pH)为3.7(95%置信度是3.4和4.1)。最小可采用的pH(此pH在23d中使生长减少5%),在盐度为30ppt时估算为5.9。同pH7.8相比较,长期(23d)置于低pH(4.9),盐度为30ppt时,对虾于民分明显减少(P<0.001),而蜕皮  相似文献   

9.
条纹石鮨摄食强度与代谢及能量收支间的关系   总被引:1,自引:0,他引:1  
设日摄食率为0.4%、1.5%、4.0%三种水平,分别测定条纹石鱼旨Moronesaxatilis幼鱼的代谢及能量的收支情况。处于饱食(日摄食率4.0%)及维持状态(日摄食率1.5%)下,该鱼代谢率增加的峰值分别于摄食后3h及7h内出现,为静止时代谢水平的2.10倍和2.46倍,SDA(特殊动力作用)持续时间均为21h,SDA总耗能量分别占摄入能的13%和35.8%。条纹石鱼旨在饱食时的转化效率K(湿重)为20.85%。三种摄食水平下条纹石鱼旨的能量收支方程分别为:饱食状态(日摄食率4.0%)时,100C=8.4F+7.8U+13.0SDA+36.9(Rs+Ra)+33.9G;维持状态(日摄食率1.5%)时,100C=7.8F+4.1U+35.8SDA+52.3(Rs+Ra),其中G=0;减重状态(日摄食率0.4%)时,(F+U+R)/(C+P1)=67.3%,其中C+P1=14.4C+85.6P1,F+U+R=1.8F+8.1U+57.4R。  相似文献   

10.
《科学养鱼》2002,(4):46-46
富溴是一种新型水体杀菌剂,为明确其产品的有效氯含量及1%药液浓度不同时间内有效氯含量的变化情况,并了解其水溶液的稳定性,我们按临床试验要求对其进行了试验,以便为防治应用及配制组方药物提供依据。一、试验材料1%富溴、4N硫酸、碘化钾、0.7%硫代硫酸钠(Na2S2O3·H2O)、1%淀粉,由实验室配制。二、试验方法试验采用碘量法。1.将富溴配制成1%溶液;2.取20毫升蒸馏水,再滴入1%富溴10滴,4N硫酸5滴,碘化钾10余粒,用玻璃棒搅匀,出现棕黄色;后在暗处静置5分钟;3.用洗净的滴管滴入0.7%…  相似文献   

11.
An 8‐week feeding trial was conducted to investigate the effects of dietary cholesterol levels on growth, feed utilization, body composition and immune parameters in juvenile oriental river prawn, Macrobrachium nipponense. Six isolipid (80 g kg?1 crude lipid) and isoproteic (400 g kg?1 crude protein) diets, supplemented with 0, 3.0, 6.0, 9.0, 12.0 and 15.0 g kg?1 cholesterol, were evaluated. Growth performance and feed utilization of M. nipponense were improved as dietary cholesterol levels increased. Weight gain and specific growth rate were highest, and feed conversation ratio was lowest, when prawns were fed a diet supplemented with 9.0 g kg?1 cholesterol. However, final body weights and survival rates of juvenile M. nipponense were not affected significantly by dietary cholesterol. Body composition of prawns, including moisture, crude protein and crude lipid, was not significantly affected by changes in dietary cholesterol. The immune parameters measured in hepatopancreas, including total antioxidant capacity, and glutathione, catalase, alkaline phosphatase and acid phosphatase activities, were at optimum levels in prawns fed with 9.0 g kg?1 dietary cholesterol. In summary, the best growth performance, lowest feed conversation ratio, and the most enhanced antioxidant capacity and immunity parameters were attained in juvenile M. nipponense when fed a diet supplemented with 9.0 g kg?1 cholesterol.  相似文献   

12.
A stocking density experiment was conducted in 18 experimental enclosures within a single 0.11 ha pond. As stocking density increased in the range 6.1–21.2 prawns/m2, school prawn growth declined while survival rate was unaffected and total harvest (final biomass) increased. A simple economic analysis indicated that the optimum stocking density for juvenile school prawns was 19.1 prawns/m2. In a similar experiment the effects of feeding school prawns with a pelleted diet at a range of supplementary feed rates (0–12.5% of prawn biomass/day) were investigated. The optimum feed rate in terms of growth was approximately 5% of biomass/day. However the optimum feed rate, in terms of the economic return index used, varied depending on the estimated cost of the diet.  相似文献   

13.
Two trials with Atlantic salmon (Salmo salar) were conducted to evaluate the potential of krill meal to improve feed intake. In the first experiment, after transfer to sea water, salmon smolts were fed diets added 75 or 150 g kg?1 Antarctic krill meal in substitution for fish meal for 13 weeks. The apparent digestibility coefficient for crude protein and the majority of the amino acids was significantly lower in the feeds added krill meal (around 83.5%) than in the control diet (84.9%), whereas the digestibility of crude lipids, dry matter and energy was not significantly different among the three diets. Krill meal addition resulted in higher feed intake, which led to higher growth rates and final body weights. In the second experiment, large salmon were fed a diet containing 100 g kg?1 krill meal for 6 weeks before slaughter. Their feed intake and growth performance were assessed, and fillet and visceral fat contents were measured. Salmon fed the 100 g kg?1 krill meal diet tended to eat more, resulting in significantly increased growth rates, when compared to control fish. Fish fed krill meal also had a significantly lower condition factor.  相似文献   

14.
This study was conducted to evaluate the effects of fulvic acid (0, 0.3, 0.6, 0.9, and 1.2%) as feed additive on growth, feed utilization, antioxidant ability, and HSP70 in hemolymph and hepatopancreas of juvenile white shrimp Litopenaeus vannamei (average weight 2.5 g) reared under experiment conditions. Shrimp were stocked at a density of 625 shrimps m?3 for 60 days in net cages submerged in recirculating tanks. At the end of the experiment, specific growth rates and survival rates of shrimp in treatment groups fed with 0.6, 0.9, and 1.2% fulvic acid were higher compared to that of the control group. Shrimp fed 0.6, 0.9, and 1.2% fulvic acid had significantly lower feed conversion rates than those fed control diet. The optimum dietary fulvic acid requirement for juvenile shrimp based on weight gain was 0.897%. Furthermore, superoxide dismutase activity and peroxidase activity increased significantly, while malonaldehyde content decreased in the hemolymph and hepatopancreas of shrimp fed 0.9 and 1.2% dietary fulvic acid. Glutathione content increased obviously in hemolymph of shrimp fed 0.6, 0.9, and 1.2% fulvic acid. In hepatopancreas, glutathione content was significantly higher in shrimp supplemented with 1.2% fulvic acid. HSP70 decreased obviously in hemolymph of shrimp fed 0.9 and 1.2% fulvic acid, while shrimp fed with 0.6 and 0.9% fulvic acid showed lower HSP70 level in hepatopancreas. The results of this study demonstrated that dietary fulvic acid could improve survival rates, growth, feed utilization, antioxidant capability, and stress resistance of juvenile L. vannamei reared under intensive stocking conditions.  相似文献   

15.
中国对虾对维生素B2、B5、B6营养需要的研究   总被引:5,自引:0,他引:5  
徐志昌 《水产学报》1995,19(2):97-104
研究了三种水溶性维生素B2,B5和B6在以酪蛋白为蛋白源的饲料中的不同含量对中国对虾的存活率,体重增重率,体长增长率,蛋白质消化率及实验维生素在体内的累积量等方面的影响。结果表明,在每100g饲料中维生素B2、B5和B6的含量分别在10(体重1.53g)-20mg(体重6.00g)、40mg、14mg时,上述指标均达最佳,维生素缺乏或过量都会阻碍对虾生长,在适宜添加量范围中,随着饲料中维生素B6的  相似文献   

16.
摄食不同饵料对翘嘴鳜生长、体成分和消化酶活性的影响   总被引:1,自引:0,他引:1  
为探究三种不同饵料对翘嘴鳜(Siniperca chuatsi)生长性能、体成分和消化酶的影响,实验选取初始体重为(113.56±11.82)g的翘嘴鳜900尾,随机分成3组,分别投喂活饵料鱼、冰鲜饵料鱼和商品饲料,进行60 d的养殖试验。结果显示:(1)冰鲜组、活饵组和饲料组翘嘴鳜的成活率、增重率、特定生长率和蛋白效率均无显著性差异。饲料组翘嘴鳜肥满度显著小于其他两组,肝体比和脏体比均显著大于其他两组。(2)三组翘嘴鳜体成分中的水分、蛋白质、粗脂肪和粗灰分均没有显著性差异。(3)翘嘴鳜肌肉各种氨基酸含量和总氨基酸量在三组之间的差异均不显著。饲料组翘嘴鳜肌肉中不饱和脂肪酸中的棕榈油酸、油酸、亚油酸、花生烯酸、EPA、神经酸、DHA的含量及总饱和脂肪酸、总单不饱和脂肪酸、总多不饱和脂肪酸均显著高于其他两组。(4)肝脏脂肪酶、肠道淀粉酶的活性在三组翘嘴鳜之间均没有显著性差异。冰鲜组翘嘴鳜肝脏淀粉酶、肠道脂肪酶活性均显著高于其他两组。结果表明:翘嘴鳜经过驯化可以摄食配合饲料,且不影响其生长性能。翘嘴鳜摄食饲料后,其肌肉氨基酸没有发生显著性的变化,不饱和脂肪酸的含量显著升高。  相似文献   

17.
We evaluated the influence of different proportions of 5′‐inosine monophosphate (IMP) and 5′‐guanosine monophosphate (GMP) on growth, feed digestibility and activity of digestive enzymes of turbot Scophthalmus maximus. Weight gain and daily feed intake were significantly higher in S. maximus fed with IMP or GMP, in comparison with fish fed with neither IMP nor GMP. The growth of 0.05% IMP + 0.05% GMP group was the best, and the intestinal digestive function was improved. The addition of IMP and GMP to fish diets significantly increased the apparent feed digestibility coefficient of dry matter and protein, as well as intestinal protease activity. The highest intestinal protease activity was observed in fish fed with 1 g/kg IMP. However, the lipase activity in hepatopancreas decreased significantly after addition of nucleic acid. According to our results, the optimal level of dietary IMP is 1 g/kg, which is in line with most of the growth performance and feed digestibility.  相似文献   

18.
This study examined the dietary requirement of arachidonic acid (ARA) when that of linoleic acid (LOA), the natural precursor to ARA, was also satisfied with linolenic acid (LNA) and also with and without the other key dietary highly unsaturated fatty acids (HUFA). Growth by prawns fed diets supplemented with ARA was poorer than in diets where it was not present. Supplementation of ARA to diets with either optimized HUFA or just optimised poly unsaurated fatty acids (PUFA) (i.e. LOA, LNA) resulted in poorer growth. Growth was poorest by prawns (215 ± 13%) fed diets with ARA supplemented at 20% of the total fatty acids but including 7% LOA, 21% LNA and 4% of both eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Growth was best in prawns fed diets devoid of ARA but with 7% LOA and 21% LNA (350 ± 19%). Prawns fed the reference diet (348 ± 21%) and the other diet devoid of ARA but containing about 7% LOA, 21% LNA and 4% of both EPA and DHA (345 ± 18%) had similar growth. The growth responses were not effects of altered lipid or fatty acid digestibilities. Indeed supplementation of ARA to the diet marginally improved the digestibility of the total neutral lipid in the diet and the digestibilities of some other dietary fatty acids. The amount of lipid in the digestive glands of prawns fed with the diets was reduced by the inclusion of ARA in the dietary lipids. Composition of the lipids in the digestive gland (DG) of the prawns was almost directly related to the composition of their dietary lipids. The proportion of ARA in the total fatty acids increased with level of supplementation of dietary ARA. An increased level of dietary ARA reduced the proportion of EPA, DHA in the DG lipid and also the total n‐3 and n‐6 fatty acids in the DG lipid. The results of this study support that addition of ARA to the diet of Penaues monodon when the other key essential fatty acids (EFA) have been optimized, does not improve their growth performance. It is suggested that key cause for this response may lie in the importance of the balance of the n‐3 to n‐6 fatty acids in the diet of these animals.  相似文献   

19.
The utilization of oleic acid as an energy source and the effects of oleic acid levels and/or dietary soy bean lecithin (SBL) on oleic acid utilization, growth and survival, and lipid class and fatty acid compositions of freshwater prawn, Macrobrachium rosenbergii (de Man), juveniles were determined.
Increase in levels of dietary oleic acid from 10 to 80 g kg−1 significantly ( P ≤ 0.05) reduced growth, survival and feed conversion efficiency of M. rosenbergii juveniles during the 40-day feeding period. Inclusion of 20 g kg−1 SBL had no significant effect ( P ≥ 0.05) on growth and survival, nor was there any interactive effect between dietary SBL and oleic acid levels.
Body fatty acid profile of prawns reflected dietary fatty acid quantity. The fatty acid composition of prawns fed diets containing 80 g kg−1 oleic acid had tremendously high proportions of oleic acid. Polar lipids, mostly phosphatidylcholine (PC), constituted the bulk of the extracted total lipids. Prawns fed with SBL had significantly ( P ≥ 0.05) higher PC content.
Oleic acid was metabolized for energy by M. rosenbergii juveniles at the same rate regardless of dietary level of SBL and/or oleic acid. Expired 14CO2 accounted for half of the ingested radioactivity 48 h after feeding with labelled diets. No significant difference in the amount of 14CO2 expired by prawns fed the labelled test diets was found. Per cent radioactivity ingested and absorbed into the body was also not significantly different in prawns of the different dietary treatments.  相似文献   

20.
Juvenile prawns (Macrobrachium rosenbergii) were stocked at 37,050/ha and golden shiner (Noremigonus crysoleucas) fry at 321,100/ha into 16 earthen ponds at Rockefeller Wildlife Refuge, Grand Chenier, Louisiana. Four replicated treatments were tested: fed prawn monoculture, fed shiner monoculture, fed prawn and fed shiner polyculture, and unfed prawn fed shiner polyculture. The study lasted 149 days. There were no significant differences in growth between prawns fed in monoculture and prawns fed in polyculture (P > 0.05). However, fed prawns grew significantly larger (P < 0.05) than unfed prawns. Prawn survival in all treatments combined averaged 63%. Survival was significantly higher (P < 0.05) for fed prawns than for unfed prawns. Prawn yields averaged 533 kg/ha, when all treatments were combined. Yield was significantly higher (P < 0.05) for prawns grown with shiners and for prawns that received supplemental feed. Growth was significantly higher (P < 0.05) for shiners grown with fed prawns than for shiners grown with unfed prawns. Shiner survival averaged 33% and was significantly higher (P < 0.05) in monoculture than in polyculture. Yield for all ponds averaged 392 kg/ha, with no significant differences between treatments (P > 0.05).  相似文献   

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