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南海黄鲷性腺发育的初步研究 总被引：1，自引：0，他引：1
本文采用常规的生物学调查方法并取黄鲷性腺做石蜡切片，用显微镜观察黄鲷的性腺发育，进行组织学研究．其结果表明，南海黄鲷精巢可分成6期，精巢5期的成熟度指数为1．62％～2．71％，平均值为1．99％．雌性生殖细胞可见5个时相，卵巢发育也相应分成6期，卵巢5期时的成熟度指数为8．90％～13．90％，平均值为9．45％．南海黄鲷的繁殖期在11月至翌年的4月，繁殖高峰在12月至3月，黄鲷的产卵类型属于在同一繁殖季节中多次产卵类型．本文还对黄鲷的雌雄同体现象、繁殖力、繁殖时间进行了讨论． 相似文献
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A 60-day feeding experiment was conducted to investigate the influence of dietary omega-3 long-chain polyunsaturated fatty acids(n-3 LC-PUFA) on growth, nutritional composition and immune function of marine fish Sebastiscus marmoratus. Five diets containing 3.6, 10.2, 18.2, 26.5, or 37.0 g/kg n-3 LC-PUFA were prepared. The results reveal significant influences of dietary n-3 LC-PUFA on the final weight, weight gain, specific growth rate, feed conversion ratio, and condition factor. As dietary n-3 LCPUFA increased, weight gain and specific growth rate increased and were significantly higher in groups fed 18.2, 26.5 and 37.0 g/kg than in groups fed 3.6 and 10.2 g/kg( P 0.05); there was no significant difference between groups fed 18.2, 26.5, or 37.0 g/kg( P 0.05). With increasing dietary n-3 LC-PUFA, eicosapentaenoic acid and docosahexenoic acid content in muscle and liver increased significantly, immunoglobulin class M content gradually increased from 9.1 to 14.8 μg/L, and lysozyme activity content increased from 1355 to 2268 U/mL. Broken line model analysis according to weight gain indicated that a dietary n-3 LC-PUFA level of 18.2 g/kg is essential for normal growth at a fat level of 125 g/kg. Therefore, appropriate dietary n-3 LC-PUFA not only promote growth and improve the n-3 LC-PUFA content, but also enhance immune function in S. marmoratus. 相似文献
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双棘黄姑鱼人工育苗技术的研究 总被引：7，自引：1，他引：7
对双棘黄姑鱼【Nibeadiacanthus(Lacepede)】催产孵化和育苗技术进行了试验研究，并从形态学方面对其近似种和易混种进行了比较。结果显示，双棘黄姑鱼性腺发育至Ⅳ期经人工催产都能产卵受精．效应时间为20～40h。胚胎发育适宜水温为22～26℃．适宜盐度为30～35，孵化率为80％～90％。在育苗水温27～29℃，盐度28～30，150万初孵仔鱼经20d培育，共育出全长1．4～2．3cm的稚鱼95．3万尾，育成率62．3％；其中32．2万稚鱼分池继续培育至36天，育出全长3．1～5．2cm的幼鱼18．4万尾。本试验说明对双棘黄姑鱼进行人工催产孵化育苗，能够培育出达到商品规格的鱼种。 相似文献
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采用单因子实验设计方法, 进行了饲料中添加维生素C对美国红鱼生长(平均增重率、存活率、特定生长率、饲料效率)和免疫反应[血清中溶菌酶活性、血清总补体活性和超氧化物岐化酶(SOD)活性]影响的研究。结果表明: 随着饲料中维生素C添加水平由0提高到100mg/kg时, 美国红鱼的增重率和特定生长率显著提高。以特定生长率为指标, 美国红鱼最佳生长性能的饲料维生素C添加量为104.5mg/kg左右; 饲料中维生素C水平在0—98.9mg/kg时, 美国红鱼肌肉和肝脏中维生素C的积累量随饲料中维生素C的增加而显著增加(P<0.05); 美国红鱼获得最大肝脏和肌肉中维生素C的积累量时饲料中维生素C最低添加量为128.1和104.0mg/kg; 美国红鱼血清溶菌酶和血清总补体活性在维生素C添加水平分别为98.9和198.7mg/kg时达到最高值, 随后变化不明显; 美国红鱼血清SOD活性随维生素C添加水平的增加而显著升高, 并且活性在198.7mg/kg达到最高值, 随后显著下降。综上所述, 美国红鱼维生素C生长和免疫的维生素C适宜添加水平为200mg/kg左右。 相似文献
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盐度对银鲳(Pampus argenteus)Na /K -ATP酶活力及血清渗透压调节激素浓度的影响 总被引：1，自引：0，他引：1
采用检测银鲳(Pampus argenteus)幼鱼鳃Na+/K+-ATP(NKA)酶活力、血清生长激素(GH)、胰岛素样生长因子Ⅰ(IGF-Ⅰ)和催乳素(PRL)浓度的方法, 研究了不同盐度下银鲳渗透压调节机制。结果表明, 鳃NKA酶活力在三种盐度下总体呈先上升后恢复的变化, 其最高点为14盐度48h时, 且显著高于其它值(P<0.05)。36盐度组的血清GH浓度显著高于其它组(P<0.05)。盐度变化均使血清IGF-Ⅰ浓度呈现先上升后恢复的变化。14盐度组血清催乳素浓度始终高于其它各盐度组。在低盐度适应(14和25)时, 血清GH浓度与NKA酶活力呈极显著正相关(P<0.01); 高盐度适应(36和25)时, 血清催乳素浓度与NKA酶活力呈显著负相关(P<0.01)。另外, 血清催乳素与IGF-Ⅰ浓度间有极显著正相关(P<0.01)。研究证明银鲳幼鱼在适应不同盐度时, 鳃NKA酶、生长激素、IGF-Ⅰ和催乳素在渗透压调节中起着重要作用, 并且相互之间存在一定关联。 相似文献
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Juvenile silver pomfret, Pampus argenteus, was grown in culture tanks for 9 weeks on four different diets, and their effects on fish growth, digestive enzyme activity, and body composition were assessed. The feeding regime was as follows: Diet 1: fish meat; Diet 2: fish meat+artificial feed; Diet 3: fish meat+artificial feed+Agamaki clam meat; Diet 4: fish meat+artificial feed+Agamaki clam+copepods. The greatest weight gain was associated with Diet 4, while the lowest weight gain was associated with Diet 1. No significant difference was observed in weight gain between fish receiving Diet 2 and Diet 3. Specific growth rate followed similar trends as weight gain. The feed conversion ratio (FCR) of fish fed Diet 1 was significantly higher than the other fish groups, but no significant differences were observed in FCRs of fish fed Diet 2, Diet 3 or Diet 4. There was also no significant difference in the hepatosomatic index (HSI) between the four diets. For fish that received Diets 2-4, containing artificial feed, higher protease activities were detected. A higher lipid content of the experimental diets also significantly increased lipase activities and body lipid content. No significant differences in amylase activity or body protein content were found between Diets 1-4. In conclusion, a variety of food components, including copepods and artificial feed, in the diet of silver pomfret significantly increased digestive enzyme activity and could improve growth performance. 相似文献
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将点带石斑鱼的受精卵置于不同盐度的水体中,观察受盐度胁迫下点带石斑鱼胚胎的沉浮 情况、卵径、油球径、孵化率、畸形率,以及卵黄囊仔鱼的形态变化和营养物质的消耗状况.结果 表明,点带石斑鱼受精卵在盐度25(含25)以下的水体中为沉性,在盐度35(含35)以上的海水中全部 漂浮于水表层,在盐度30和对照组31的水体中大部分胚胎浮在水上层.受精卵卵径随孵化盐度降低而减小.在水温26-28℃的条件下,点带石斑鱼受精卵经21-26h可孵化成仔鱼,盐度对孵化时间影响不显著(P>0.05).盐度在15-50范围内都能孵出仔鱼,但孵化率和畸形率因盐度不同而有显著差异.综合分析表明点带石斑鱼受精卵孵化的适合盐度范围为26.7-41.1.最适孵化盐度范围在30.5-32.5之间.盐度对卵黄囊仔鱼可量性状的影响主要表现在卵黄囊容积和全长的变化,高盐度(≥45)下胚后仔鱼卵黄囊容积、全长和体高显著减小(P<0.05),油球径不因盐度不同而改变. 相似文献
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东海区养殖对虾暴发性流行病病原及防疫对策 总被引：4，自引：0，他引：4
１９９３年东海地区的养殖对虾发生严重的暴发性流行病，病情发展迅猛，死亡率高。在一个养虾塘中，从发现摄食量减少到大批死亡仅２～３ｄ；少数虾塘，疾病表现为亚急性的，每天死亡一些，可延续半个月以上，最终大部分死亡。采用各种药物均无法控制病情的发展。疾病流行面很广，波及苏、沪、浙、闽三省一市，使整个东海地区的对虾养殖业遭受惨重损失。现将调查结果作简要报道。１对虾暴发性流行病概况东海区对虾暴发性流行病从时间和地域上分析，可以长江口为界分为南、北两个疫区。长江以南疫区福建省继１９９２年全面暴发虾病后，１９９… 相似文献
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盐度是影响对虾存活、生长的重要因子。对虾对盐度的适应除与温度、对盐度变化的适应时间、发音阶段、蜕壳期等因子有关外,还与个体大小密切相关。有关斑节对虾仔虾对盐度的适应已有许多报道,Cawthorne(1983)报道了第28天的仔虾对盐度的适应能力强于40K以后的仔虾;Chakraborti(1986)用1.0～1.2厘米仔虾为材料作了盐度变化对其存活率的影响试验;林美云(1982)也用头胸甲长0.53～0.74厘米(体长约1.5～ 相似文献
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