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21.
银线伞莎草组织培养及快速繁殖的研究   总被引:1,自引:1,他引:0  
周博  许维倩  李娜  徐娜  姜长阳 《北方园艺》2010,(17):150-152
以银线伞莎草的总苞片为材料,进行了组织培养研究,成功地建立起快速繁殖体系。结果表明:1/2MS+BA0.4mg/L+NAA0.1mg/L+蔗糖20~30g/L是总苞片萌发生长为无根苗的适宜培养基;1/2MS+IBA0.2mg/L+IAA0.3~0.4mg/L+蔗糖20g/L是无根苗生根培养的适宜培养基;MS+IBA0.2mg/L+IAA0.3mg/L+BA0.2mg/L+GA30.5mg/L+蔗糖20g/L是银线伞莎草根茎萌发生根培养和根茎萌发生根继代增殖培养的适宜培养基;在温室中试管苗移栽易成活,移栽的试管苗保持了银线伞莎草的特有性状,且生长旺盛。  相似文献   
22.
鳢(Channa)是我国重要的淡水鱼类,具有较高的经济价值.鳢普遍存在显著的性别二态性,雄性个体生长速度快、个体大、饲料系数低,因此,全雄单性养殖具有重大的经济意义.阐述了全雄乌斑杂交鳢性别控制育种过程:利用性别分子标记辅助育种技术和生殖内分泌调控技术创制超雄斑鳢新种质,开展母本乌鳢2代群体选育,然后超雄斑鳢与选育的母...  相似文献   
23.
比较普通乌鳢和金黄色乌鳢肌肉营养成分,为金黄色乌鳢的营养价值研究提供理论依据。采用国际标准检测方法,分别测定普通乌鳢和金黄色乌鳢肌肉的常规营养成分、氨基酸和脂肪酸的含量,并用SPSS16.0对测定结果进行分析。结果显示,2种乌鳢肌肉中粗蛋白、粗脂肪和灰分的含量没有表现出显著差异(P>0.05),金黄色乌鳢肌肉中水分含量显著高于普通乌鳢(P<0.05);2种乌鳢检测出的17种氨基酸中谷氨酸(Glu)含量最高,半胱氨酸(Cys)含量最低,EAA/TAA和EAA/NEAA的比值分别在39.29%~39.66%和77.20%~79.36%之间;2种乌鳢饱和脂肪酸、不饱和脂肪酸、单不饱和脂肪酸和多不饱和脂肪酸总量差异不显著(P>0.05),均含有EPA和DHA,差异不显著,而金黄色乌鳢油酸和亚油酸含量显著高于普通乌鳢。金黄色乌鳢不仅与普通乌鳢同样具备较高的营养和保健价值,还具备特有的观赏价值,具有良好的开发利用前景。  相似文献   
24.
A study was conducted to determine the artificial breeding response, embryonic and larval development of giant snakehead, Channa marulius, with the application of various dosages of stimulatory hormones: Suprefact® (LHRH) agonist and Ovaprim® (GnRH + dopamine inhibitor). First and second hormonal dosages of Suprefact® (diluted) and Ovaprim® (0.3, 0.4, and 0.5 ml for male and 0.8, 0.9, and 1.0 ml for females per kilogram body weight) were used. There were three treatments T1, T2, and T3 and each treatment had three replicates. Male fish were treated with T1 (0.3), T2 (0.4), T3 (0.5) ml kg−1 of body weight while female fish with T1 (0.8), T2 (0.9), T3 (1.0) ml kg−1 of body weight. The results showed that fish stimulated with T3 (1.0) obtained better fecundity rate (2951.7) followed by T2 (0.4) (2678.3), while the lowest fecundity (466.7) was recorded in T1. The numerically higher values of gonado-somatic index (males and females) and fertilization rate appeared in T2. The highest survival rate (97.1%) was found in T3 followed by T2 (97.0%), while the lowest (32.2%) in T1. In conclusion, the application of Suprefact® and Ovaprim® at 0.4 and 0.5 ml kg−1 body weight for male and 0.9 and 1.0 ml kg−1 for female fish successfully stimulated snakehead fish induced breeding.  相似文献   
25.
本文简要地综述了我国乌鳢的养殖现状,分析了乌鳢的养殖发展前景,同时提出了开发乌鳢养殖业的对策。  相似文献   
26.
Tail and fin rot disease (TFRD) is a big issue in the production of spotted snakehead, Channa punctata Bloch. The aims of the present study were to isolate and identify the bacterial pathogen causing TFRD, to detect histopathological changes in tissues (fin, tail, liver, and kidney), and to ascertain the antibiotic sensitivity pattern of the isolate. Out of six bacterial isolates, only the isolate DJ1990 was found to be the causal candidate of TFRD in C. punctata. Identical histopathological changes were detected in tail, fin, liver, and kidney under light and scanning electron microscope in both collected diseased fish and artificially infected fish. The isolate was identified as Pseudomonas aeruginosa strain DJ1990 (National Center for Biotechnology Information Ace. No. KX709967) based on the biochemical characterization tests and 16S rDNA sequence‐based phylogeny analysis. Artificial challenge test demonstrated that the strain DJ1990 was highly virulent (100% mortality at 48 h of postinjection period at the concentration of 1.5 × 107 CFU/g of body weight) for C. punctata. The isolate exhibited sensitivity to the broad‐spectrum antibiotics but was resistant against aztreonum. To the best of our knowledge, this is the first report of P. aeruginosa as a TFRD‐causing candidate in C. punctata.  相似文献   
27.
The present study investigated the effects of dietary astaxanthin on the growth, blood biochemical, antioxidant, immune and inflammatory response in lipopolysaccharide‐challenged Channa argus. A total of 0, 50, 100 and 200 mg/kg of astaxanthin were added to the basal die for 56 days. After the feeding experiment, each group was subjected to a lipopolysaccharide challenge (except for the Control group). The results showed that adding astaxanthin to the diet can significantly increase the weight gain and specific growth rate and decrease the feed conversion ratio of C. argus; the highest weight gain, specific growth rate and minimum feed conversion ratio occurred in the 100 mg/kg group. Furthermore, dietary astaxanthin supplementation can alleviate the negative effects of lipopolysaccharides by increasing the levels of alkaline phosphatase, lysozyme, complement 3, complement 4, total serum protein, albumin, globulin, superoxide dismutase, catalase and glutathione peroxidase and decrease the serum cortisol, aspartate aminotransferase, alanine aminotransferase, glutathione peroxidase, and malondialdehyde. Dietary astaxanthin supplementation also can decrease the relative expression of inflammatory genes (nuclear factor κB, interleukin‐1, interleukin‐8 and tumour necrosis factor‐α) in the liver, spleen, kidney and intestine. To summarise, dietary astaxanthin addition can improve the growth performance and attenuate the negative effects of lipopolysaccharide challenge in C. argus. The optimal amount of astaxanthin is 100 mg/kg.  相似文献   
28.
Isoleucine requirement of fingerling Channa punctatus (6.74 ± 0.09 g) was estimated by feeding seven trial diets (450 g/kg CP, 14.73 kJ/g DE) containing 3.8, 7.5, 11.3, 15.1, 19.3, 23.2 and 27.4 g/kg of isoleucine for 12 weeks. Growth and haematological parameters increased with the increasing concentrations of dietary isoleucine up to 16 g/kg. Carcass protein and fat increased significantly with the increasing concentrations of dietary isoleucine up to 16 g/kg and then stabilized. Moisture content showed reverse trend to that of carcass fat. Hepatosomatic index was found to be highest at 4 g/kg of dietary isoleucine. Viscerosomatic index and condition factor increased significantly with increasing levels of isoleucine up to 16 g/kg dry diet. Serum protein, lysozyme and superoxide dismutase activities were also found to increase significantly up to 16 g/kg dry diet. Significant reduction in alanine aminotransferase and aspartate aminotransferase activities was observed by increasing concentrations of dietary isoleucine up to 16 g/kg. Based on quadratic regression analysis of absolute weight gain, feed conversion ratio, protein retention and isoleucine retention efficiencies against varying concentrations of isoleucine, the optimum isoleucine requirement ranging between 17.95 and 18.39 g/kg dry diet, corresponding to 39.88–40.86 g/kg dietary protein, is recommended for maximizing growth of C. punctatus.  相似文献   
29.
为了解养殖池塘水体化学耗氧量的变化特征,于2012 年在佛山市顺德区内4 种不同养殖品种(云斑尖 塘鳢、草鱼、大口黑鲈、乌鳢)池塘采集样品进行分析。结果显示院不同时期4 个品种养殖池塘CODMn含量在3.71~ 50.76 mg/L 之间,其中大口黑鲈、乌鳢两个品种养殖池塘季节的变化有显著差异;云斑尖塘鳢、草鱼池塘的CODMn 含 量没有明显的季节性变化。不同品种养殖池塘CODMn含量从低到高依次为云斑尖塘鳢、大口黑鲈、草鱼、乌鳢。养殖 池塘水体CODMn污染指数(Pi)范围在0.67~8.46 之间,超标率为92.9%。图谱分析结果显示,5~8 月间不同养殖池塘 水体中云斑尖塘鳢、大口黑鲈养殖池塘CODMn有比较相近特征,而草鱼、乌鳢养殖池塘与其他池塘特征相差较大。9~ 12 月间不同养殖池塘水体中CODMn 云斑尖塘鳢、草鱼、大口黑鲈养殖池塘有比较相近特征,而乌鳢养殖池塘与其他 池塘特征相差较大。对CODMn 与14 个水质因子进行相关分析发现,CODMn 与透明度、pH 值及硅酸盐存在负相关关 系,与盐度、电导率、叶绿素、磷酸盐、硝酸盐、氨氮等存在正相关关系,而与溶解氧及非离子铵不相关。  相似文献   
30.
斑鳢含肉率及肌肉营养成分的测定   总被引:5,自引:1,他引:5  
对斑鳢的含肉率和肌肉营养成分进行了测定,试验结果表明,斑鳢含肉率平均为(58.40±3.21)%,粗水分75.39%、粗蛋白25.75%、粗脂肪4.70%、粗灰分1.08%、磷0.55%、钙 0.78%.肌肉蛋白中含有18种氨基酸,总量为79.64%(干样),其中人体必需氨基酸总量是 30.23%,占氨基酸总量的37.94%;鲜味氨基酸含量为30.79%,较月鳢、青鱼、草鱼、鲢、鳙的高.斑鳢是一种蛋白质高,味道鲜美,易于人体消化吸收的优良淡水鱼品种.  相似文献   
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