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91.
Serum biochemical parameters are important aspects in the management of endangered species, such as Acipenser persicus. The values of these parameters can be used for confirming the maturity and for monitoring any changes in the quality of waters and related soils. Serum samples of 44 A. persicus fishes were analyzed and their serum parameter values were determined as Mean±SD in four groups: mature males and females and immature males and females, respectively. We compared the levels of calcium (Ca; 1.97 ± 0.31–2.38 ± 0.28 mmol/l), blood urea nitrogen (BUN; 4.4 ± 0.54–6.16 ± 0.63 mmol/l), cholesterol (CHO; 2.55 ± 0.42–3.51 ± 0.65 mmol/l), creatinine (CREA; 27.23 ± 3.5–83.98 ± 7.5 mmol/l), magnesium (Mg; 2.74 ± 0.18–3.05 ± 0.46 mmol/l), bilirubin (Bilirubin; 2.05 ± 0.42–13.93 ± 4.39 μmol/l), aspatate transaminase (AST; 18.25 ± 1.5–167 ± 38 Iu/l), alanine transaminase (ALT; 11 ± 1–25.33 ± 9.24 Iu/l), alkaline phosphatase (ALP; 183.5 ± 17.68–523 ± 66.23 Iu/l) and creatine kinase (CK; 157.5 ± 27.58–2132.2 ± 250.92 Iu/l). We have shown that there were no differences in the Ca and Mg levels among the different groups. However, mature females have higher CREA, AST, CHO and lower BUN, ALP and ALT than the immature females. In the mature males, the values of ALP and bilirubin were higher yet the values of CREA and ALT were lower than in the immature males.  相似文献   
92.
High-energy diets for white sturgeon, Acipenser transmontanus Richardson   总被引:1,自引:0,他引:1  
Four diets formulated for salmon were fed to 0.11 kg white sturgeon, Acipenser transmontanus Richardson, for 8 weeks. Dietary compositions ranged from 258 to 402 g lipid kg−1, 535–378 g protein kg−1 and 22.7–14.4 g protein MJ−1 gross energy.
Fish in all treatments grew rapidly, utilized the diets efficiently and had body compositions similar to what has been found in previous studies, but there were some dietary effects. Sturgeon fed the diet with the highest lipid content and lowest protein/energy ratio had lower ( P < 0.05) specific growth rate, feed efficiency, and liver moisture and protein contents, and 6-phosphogluconate dehydrogenase activity, but higher liver lipid contents than fish fed the other three diets. Condition factor, organ to body weight ratios, whole-body and plasma concentrations of protein, glucose and triglyceride, and liver glucose-6-phosphate dehydrogenase, isocitrate dehydrogenase and malic enzyme activities did not differ significantly among dietary treatments. This suggests that white sturgeon subyearlings can utilize diets with high lipid contents (258–357 g kg−1) to display good growth without major adverse effects on body composition and liver lipogenic enzyme activities.  相似文献   
93.
An immunohistochemical study of the sturgeon (Acipenser baeri) pituitary was undertaken using antisera directed against hormones from various classes of vertebrates, including the only pituitary hormone available from sturgeon, gonadotrophin. A positive reaction was obtained after application of antisera towards the following hormones 1–24 synthetic ACTH (1-24 ACTH), melanophore stimulating hormone (MSH), ovine prolactin (oPRL), ovine growth hormone (oGH), salmon growth hormone (sGH), carp gonadotrophin (cGTH) and its beta subunit (cGTH), sturgeon gonadotrophin (aciGTH), carp thyrotrophin (cTSH) and subunit of the human thyrotrophin (hTSH). The results demonstrate that, in general, the sturgeon pituitary resembles that of teleosts as regards the distribution of the different cell types: ACTH and PRL cells in the rostral pars distalis, GTH, TSH and GH cells in the proximal pars distalis and MSH and PAS-cells in pars intermedia. In addition to the topographical organization of the sturgeon pituitary, this study provides data on the immunological relationships between sturgeon pituitary hormones and those of other vertebrates.  相似文献   
94.
史氏鲟幼鲟对饲料中磷的需要量   总被引:1,自引:1,他引:0  
文华  严安生  高强 《水产学报》2008,32(2):242-248
通过生长饲养试验研究史氏鲟幼鲟对饲料中磷的需要量.以Ca(H2PO4)2·H2O为磷源,配制含磷水平分别为0.18%(对照组),0.40%,0.71%,0.98%,1.38%和1.66%的6组等能等氮纯化饲料,每组饲料饲喂3个重复,每个重复饲养20尾初体质量约为4.7 g的幼鲟.经过8周的饲养后,对生长、饲料效率、成活率、幼鲟肌肉常规组成及脊椎骨灰分和钙磷含量进行分析.结果表明,随饲料中磷含量的升高,鱼体增重率、饲料效率和特定生长率显著增加(P<0.05),直至0.98%组达最大,然后随着饲料磷含量的增加,这些指标显著降低(P<0.05);试验各添加组的成活率显著高于对照组(P<0.05),但各添加组间没有显著差异(P>0.05);饲料添加磷对鱼体肌肉水分、粗蛋白质和粗脂肪含量无显著影响(P>0.05);当饲料磷含量在0.71%~1.66%之间时,脊椎骨中灰分、钙和磷含量差异不显著(P>0.05),但显著高于对照组和0.40%试验组(P<0.05).经过折线回归分析得出,为维持史氏鲟幼鲟最佳生长和骨骼磷水平,饲料中磷的需要量为0.88%~1.00%(占干饲料).  相似文献   
95.
胡红霞  刘晓春  朱华  张勇 《水产学报》2008,32(6):817-824
用蛋白质快速液相层析(FPLC)分离俄罗斯鲟鱼脑垂体促性腺激素(GtH),共获得GtH纯化蛋白4.6mg。用SDS-PAGE变性胶电泳图谱初步分析纯化蛋白,用反相高效液相色谱(rpHPLC)分离出两个亚基,质谱测定α亚基分子量:15603KD,两个β亚基分子量分别为14338KD和14694KD。制备了鲟鱼GtH的兔抗血清多克隆抗体,采用氯胺T法用125I标记抗原,用羊抗兔γ球蛋白做二抗,建立鲟鱼GtH的放射免疫测定方法。测定了催产前后不同时间史氏鲟血清中GtH含量的变化,统计分析表明成功排卵的雌鱼比未排卵和阴性对照组在催产后12小时和16小时GTH分泌量升高显著,最高达到234ng/ml;催产效应时间与催产后血清中GtH的含量紧密相关。  相似文献   
96.
文章列举了鲟鳇鱼及其产品的经济价值,阐明了其保护等级,对黑龙江省鲟鳇鱼的自然资源及人工养殖情况的历史阶段变化作了详细的介绍,对当前的开发利用及资源保护情况进行了深入的研究和分析,指明了在当前鲟鳇鱼开发利用及资源保护工作中存在的问题,并针对问题提出了相应的对策建议。  相似文献   
97.
The aims of this study was to assess the effect of two lactic acid bacteria (LAB), Lactobacillus curvatus and Leuconostoc mesenteroides, originally isolated from gastrointestinal (GI) tract of beluga (Huso huso) and Persian sturgeon (Acipenser persicus), respectively, on growth, survival and digestive enzyme (amylase, lipase and protease) activities and the population level of LAB in the GI tract. The treatments included 10 different groups; control, separate supplements of Lcurvatus and Leumesenteroides at three different counts [2 × 109, 5 × 109 and 9 × 109 colony forming units (CFU) per gram food] and three combinations of the two LAB (2 × 109 + 2 × 109, 5 × 109 + 5 × 109 and 9 × 109 + 9 × 109 CFU per gram food). The bacteria used in this study were added in lyophilized form to chopped Chironomidae. In the beluga study, highest specific growth rate, survival and improved intestinal enzyme activities were noted in the rearing group fed 9 × 109 L. curvatus per gram food. In Persian sturgeon, the inclusion level of 2 × 109 Leu. mesenteroides had similar positive effect. The ability of LAB to colonize the digestive tract seems to involve host specificity, and our bacteriological results are relevant to initiate future probiotic studies in sturgeons and future directions will be discussed.  相似文献   
98.
中国的鲟鱼养殖   总被引:9,自引:0,他引:9  
以作者的研究经历及国内外相关资料为基础,重点介绍了我国鲟鱼养殖产业和养殖技术研究的发展历史、我国的鲟鱼及其目前的主要养殖种类、养殖地区、生产方式、生产量和产业发展趋势,并针对产业发展面临的主要问题提出建议。  相似文献   
99.
施氏鲟幼鱼的耗氧速率及窒息点   总被引:1,自引:0,他引:1  
在两种不同温度下测定施氏鲟幼鱼的耗氧速率和窒息点,结果表明:施氏鲟幼鱼的耗氧速率随水中溶解氧增减而升降,其呼吸类型属顺应型,耗氧速率还随水温的升高而增大,随鱼体的增大而降低;在溶氧接近饱和值情况下,14℃水温时,平均体重7.8-26.9克鱼的耗氧速率为0.31-0.24mgO2/g/hr,窒息点1.35-1.32mgO2/L,水温25℃时,平均体重8.0-17.2克鱼的耗氧速率为0.61-0.53mg/O2/g/hr,窒息点为2.18-2.10mg/O2/L。  相似文献   
100.
研究了2009年5-9月鲟亲鱼养殖池塘中浮游生物的种类组成,细胞数量、优势种组成和随季节的变化。结果显示:鲟亲鱼的活动导致养殖池塘沉积物再悬浮,水体透明度较低。浮游植物的种类组成以绿藻门(Chlorophyta)的月牙藻(Selenastrum spp.)和小球藻(Chlorella spp.)等小型个体为主,浮游植物密度1.0883×lO^7ind./L—1.5662×lO^7ind./L,生物量14.6438~19.2535mg/L。浮游动物以轮虫(Rotifera)和桡足类(Copepoda)为优势种群,浮游动物密度162.0000ind/L~560.0000ind/L,生物量0.3795~1.5482mg/L。研究显示,鲟亲鱼的活动是决定池塘浮游生物的群落结构变化的重要过程之一。  相似文献   
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