饥饿和再投喂对西伯利亚鲟生化组成的影响

试验设饥饿0、3、6、9、12 d(记为S0(对照)、S3、S6、S9、S12组),然后各恢复投喂20 d,分析了饥饿和再投喂对西伯利亚鲟Acipenser baeri生化组成的影响。结果表明:饥饿结束时,S6和S9组蛋白质含量略高于S0组,S3、S12组略低于S0组,但差异均不显著;除S3组外,各饥饿组脂肪含量均低于对照组,且S6组有显著差异(P<0.05);各组鱼体水分含量有所上升,其中S12组与S0组差异显著(P<0.05)。恢复投喂后,S3、S12组蛋白质含量低于S0组,S6、S9组蛋白质含量高于S0组,但差异均不显著;各组鱼的脂肪含量均升高,但各饥饿组的脂肪含量均低于对照组,且S9组达到显著水平(P<0.05);各组水分含量下降,其中S12组变化显著(P<0.05)。     

氟离子对西伯利亚鲟胚胎发育的影响

本试验在水温17±1℃的条件下,采用半静态式生物毒性试验方法,探讨了氟离子(F-)对西伯利亚鲟胚胎发育的影响。结果表明,100~600 mg/L氟暴露会导致胚胎孵化延迟,氟暴露组半数孵化时间(MHT)比对照组推迟9~22 h。氟暴露同时导致胚胎死亡率显著增加(P<0.05),出膜仔鱼活力减弱、存活时间缩短、畸形率显著升高(P<0.05),出现卵黄囊畸形、脊椎畸形、眼部充血等畸形症状。试验得出F-致西伯利亚鲟胚胎144 h半致死浓度(LC50)为447.61 mg/L,孵化安全浓度(SC)为4.48 mg/L,导致仔鱼畸形的半数效应浓度(EC50)为536 mg/L。氟对西伯利亚鲟胚胎的安全质量浓度低于我国部分高氟地区地下水、地表水及人为氟污染水域中氟含量,提示天然水体中氟可能会对鱼类胚胎产生负面影响,应引起重视。     

电麻醉对西伯利亚鲟幼鱼行为特性与血清离子浓度的影响

研究了不同强度电麻醉对西伯利亚鲟幼鱼行为特性与血清离子浓度的影响。西伯利亚鲟电麻醉阶段包括部分失去平衡期、完全失去平衡期、完全麻醉期和鳃动停止期等4个时期。电麻醉时西伯利亚鲟呈现趋阳性;随着电压升高,到达各麻醉阶段时间与恢复时间逐渐缩短。西伯利亚鲟到达完全麻醉期时间在15 V、20 V、25 V、35 V组间均有显著差异,在30 V与35 V时分别仅为97.0 s和68.8 s,而恢复时间为0 s。各试验组西伯利亚鲟在电麻醉时鳃动频率均增加,而恢复阶段均降低。电麻醉对西伯利亚鲟摄食与活动状态均无显著影响。随着电压升高,钾离子与镁离子浓度先下降后上升,钙离子则先上升后下降。钠离子与氯离子浓度变化较大,均是15 V组时浓度最低,20 V时浓度最高。磷离子浓度呈现增高趋势。pH值在麻醉后降低,对照组与其余各组均有显著性差异。因此西伯利亚鲟幼鱼适宜电麻醉强度为25~30 V,电麻醉是种较好的麻醉方法,具有广泛的应用前景。     

倪氏复口吸虫尾蚴和后囊蚴体壁的超微结构观察

复口吸虫在我国东北、华东、华中、华南等地均有分布,能引起淡水鱼类复口吸虫病的广泛流行,其中尤以华中一些省份为甚[1-2]。研究发现引起华中地区复口吸虫病流行的主要是倪氏复口吸虫(Dip-lostomum niedashui)和湖北复口吸虫(D.hupe-hensis)[1]。为了对尾蚴和后囊蚴的形态分类     

延迟投饵对杂交鲟仔鱼生长、存活和体成分的影响

以杂交鲟(Huso huso ×Acipenser baeri )仔鱼为研究对象,将其分为 8个处理组,每组100尾(各设2个平行组),分别在孵化后6 d(对照组)、8 d、10 d、12 d、14 d、16 d和18 d开始投喂冰冻卤虫和碎水蚯蚓(以质量比1:1混合),5 d后只投喂碎水蚯蚓。第8组为饥饿组,从不投饵。水温17 ℃,实验周期30 d。结果显示,仔鱼于孵出后8日龄进入混合营养期;10日龄左右是仔鱼开始加速生长的关键时期;12日龄仔鱼进入外源性营养期。随起始投饵时间的延迟,仔鱼的全长、湿重、干重和粗蛋白含量下降,鱼体水分含量则随之升高。但对照组、8日龄及10日龄起始投喂组之间的鱼体水分、粗蛋白、粗脂肪含量并没有显著差异(P>0.05),14日龄及其以后各起始投喂组仔鱼的生长和鱼体生化成分则与上述各组存在显著差异(P相似文献   

The effects of different fishmeal level diets with or without phytase supplementation on growth performance,body composition,digestibility, immunological and biochemical parameters of juvenile hybrid sturgeon (Acipenser baeri Brandt ♀ × A. schrenckii Brandt ♂)

A 12‐week growth trial was conducted to evaluate the effect of low fishmeal and phytase replacing inorganic phosphorus on juvenile hybrid sturgeon (Acipenser baeri Brandt ♀ × A. schrenckii Brandt ♂). Four experimental diets were designed as FM100p, FM100, FM250p and FM250, which represented 10% and 25% fishmeal with or without phytase, respectively. The results showed that although growth parameters had no significant difference in all treatments, low fishmeal obviously decreased the culture cost of hybrid sturgeon. Lipid content of body composition was obviously increased in low fishmeal treatments (p < .05). The interaction of low fishmeal and phytase significantly enhanced apparent digestibility coefficients of crude protein (p < .05). Two‐way ANOVA analysis showed that input and output of phosphorus were significantly affected by fishmeal level, phytase and interaction of both factors (p < .05). For the immunological and hepatic function parameters, fishmeal level and phytase had significant effects on the activities of lysozyme, myeloperoxidase, malondialdehyde, alanine aminotransferase, lactate dehydrogenase and alkaline phosphatase (p < .05). The present study potentially justifies that a diet containing 10% fishmeal can be used for hybrid sturgeon. Moreover, replacement of monocalcium phosphate by phytase not only has no adverse effect on the growth of hybrid sturgeon, but also reduces phosphorus emission and protects aquaculture environment.     

西伯利亚鲟（Acipenser baeri）养殖群体遗传结构的AFLP分析

本研究构建了西伯利亚鲟（Acipenser baeri）扩增片段长度多态性（AFLP）分析体系,分析了DNA提取、双酶切反应、连接反应、预扩增反应、选择性扩增反应和银染等步骤。用7对引物对24尾西伯利亚鲟进行了AFLP分析,每对引物扩增的位点数在24～39之间,共扩增出了234个位点,多态性位点为116个,多态性比例为48.83%,平均Nei氏基因多样性指数H为0.4297,平均Shannon氏指数I为0.1233,个体间平均遗传距离为0.1872,表明西伯利亚鲟养殖群体的遗传多样性程度比较低,同时还构建了西伯利亚鲟的聚类图。     

氟苯尼考及氟苯尼考胺在西伯利亚鲟体内的药动学及组织分布

采用液质联用法(HPLC-MS/MS)建立了氟苯尼考和氟苯尼考胺同时检测的方法,研究了氟苯尼考口灌给药西伯利亚鲟后,氟苯尼考及其代谢物氟苯尼考胺在西伯利亚鲟体内的药动学和组织分布。水温22℃下,氟苯尼考以15 mg/kg剂量单次口灌给药西伯利亚鲟,检测血浆、肝脏、肾脏和肌肉等组织中氟苯尼考及其代谢产物氟苯尼考胺的浓度,结果显示:氟苯尼考及其代谢产物氟苯尼考胺在西伯利亚鲟体内的药时数据均符合一级吸收二室开放模型,氟苯尼考在血浆中的达峰浓度(Cmax)为3.4μg/mL,达峰时间(Tpeak)为2.943 h,表观分布容积(V/F)为3.267 L/kg,消除半衰期(t1/2β)为31.21 h,药时曲线下总面积(AUC)为76.51μg.h/mL,Cmax(FFA)/Cmax(FF)和AUCFFA/AUCFF仅为5.44%和20.73%;氟苯尼考在各组织中分布广泛,分布规律相近,肝脏、肾脏中药物浓度较高。结果表明:氟苯尼考在西伯利亚鲟体内具有吸收迅速、达峰浓度高、消除相对缓慢及组织中分布广泛的特征且氟苯尼考主要以原形药物形式代谢消除。研究亮点:针对氟苯尼考目前广泛用于水产养殖中细菌性疾病防治的现状,本文首次采用液质联用法进行了氟苯尼考及其代谢产物氟苯尼考胺在西伯利亚鲟体内分布及代谢规律的研究。建立了比较简单的样品处理方法,并从药物本身和代谢产物整体来研究药动学及组织分布特征,为制定该药安全使用方法提供了理论基础。     

Effects of totally replacing dietary fish oil by linseed oil or soybean oil on juvenile hybrid sturgeon,Acipenser baeri Brandt♀×A. schrenckii Brandt♂

The growth performance, body composition, fillet fatty acid content, serum hepatic enzymes and postprandial changes in serum lipid metabolism of hybrid sturgeon (70.8 ± 0.5 g) were investigated to determine the effects of total replacement of 80 g kg^‐1 fish oil (diet A) with linseed oil (diet B) and soybean oil (diet C), respectively. No significant differences in weight gain rate and specific growth ratio were observed among all fish groups (p > .05). Diet A fish group had the highest, but diet B fish group had the lowest feed intake (p < .05). Feed efficiency of fish fed diet A was significantly lower than the other two fish groups (p < .05). Fish fed diet A had the lowest fillet and liver lipid contents (p < .05). Serum lactate dehydrogenase, alanine aminotransferase and aspartate aminotransferase activities of fish fed diet A were significantly lower than those of fish fed diets B and C (p < .05). The contents of linoleic acid (C18:2n6) and linolenic acid (C18:3n3) in fillets showed a significantly positive linear correlation with the diets. Serum glucose and non‐esterified fatty acid were just affected by the time point (p < .05). The lipid source, time point and interaction of both factors had significant effects on serum triglyceride, high‐density lipoprotein cholesterol and low‐density lipoprotein cholesterol (p < .05). Serum total cholesterol was only affected by interaction of time point and lipid source (p < .05), and ketone body was not affected by lipid source, time point or interaction of both factors (p > .05). In summary, total replacement of fish oil with linseed oil or soybean oil had no significant adverse effects on hybrid sturgeon growth during 84‐day period, and linoleic acid and linolenic acid in fillet were modified by dietary treatments.     

饲料中不同水平磷对西伯利亚幼鲟(Acipenser baeri)血浆生化指标的影响

选择平均体重14.5±1.0g,体长16.0±0.5cm的西伯利亚鲟鱼,随机分成11组,每组3个重复,每个重复15尾.试验以磷酸二氢钙为磷源,配成磷含量分别为0.12%、0.20%、0.29%、0.39%、0.48%、0.60%、0.69%、0.80%、0.99%、1.19%和 1.38%的11组饲料,研究饲料中不同水平磷对西伯利亚幼鲟血浆生化指标的影响.结果表明:血浆总蛋白含量、白蛋白含量和球蛋白含量随饲料磷含量的增加呈逐渐上升趋势,在饲料磷含量0.69%时达最高(18.81g/L、6.99 g/L、11.63 g/L),然后随磷水平升高又逐渐下降;当饲料中磷含量大于0.29%时,磷含最对血浆中总胆固醇和甘油三酯含量_尢显著性影响(P>0.05);由血浆蛋白含量可以得出:西伯利亚鲟最适磷需要量为0.69%.