水温和养殖密度对大鳞鲃幼鱼的生长影响

分别进行水温和密度对大鳞鲃(Barbus capito)幼鱼的生长影响实验,旨在探索大鳞鲃适宜的放养密度和生长温度。水温实验设计为6个梯度值15℃、18℃、21℃、24℃、27℃、30℃,幼鱼初始体重为9~12 g,投喂75 d后,结果得出:在水温15~27℃时,随着温度的升高,终末体重会逐渐增加,27℃时最大值为(44.47±9.54)g,水温达到30℃时,终末体重开始下降。24℃、27℃和30℃组体重增长无显著差异,但温度达到30℃时,体重变异系数最大,为(29.82±11.36)%。密度实验设计为4个梯度值20 ind/m3、15 ind/m3、10 ind/m3、5 ind/m3,幼鱼初始体重为0.6~0.7 g,投喂60 d后,结果得出:随着放养密度的下降,体重增长的速度越快。体重、特定增长率、日增重变化在密度为5 ind/m3时最高,密度10 ind/m3与15 ind/m3没有显著差异,达到20 ind/m3时会显著下降。综合考虑,大鳞鲃适宜的养殖温度在24~27℃,静水池塘的放养密度建议在15 ind/m3左右。     

北方寒地池养大鳞鲃生长和越冬成活

池塘人工养殖条件下测定了大鳞鲃(Barbus capito)的生长和越冬存活率,结果得出,水温20～23℃时大鳞鲃仔鱼的全长与生长时间相关方程为L全长=0.577 9t天数+5.422 1(R2=0.994 2,n=30);池塘水温13～28℃时,1龄鱼体长与生长时间的相关方程为L=18.234e0.132 6t(R2=0.978 5,n=30),体重与体长的关系式为W=0.017 3 L2.953 6(R2=0.9976,n=30)。夏季(5～10月)在室外池塘饲养,冬季(11～4月)自然越冬条件下,大鳞鲃1龄鱼体重为(40.06±6.53)g,2龄鱼体重为(241.35±45.31)g;夏季饲养条件不变,冬季在室内水泥池中(水温15～23℃)饲养条件下,12月龄体重为(90.02±32.17)g,24月龄为(807.27±150.46)g,30月龄为(1 380.08±176.26)g。大鳞鲃采取在越冬池中饲养,冬季直接在原塘自然越冬,存活率可达90%以上。     

大鳞鲃鱼同工酶的研究

本实验采用聚丙烯酰胺垂直平板电泳方法,分析了大鳞鲃鱼的肝、肾、眼3种组织中的醋酶（EST）、淀粉酶（AMY）、乳脱酸氢酶（LDH）和苹果酸脱氢酶（MDH）4种同工酶。结果表明各种同工酶具有明显的组织特异性,肝脏酶活性最高,具有所有酶带。     

大鳞鲃鱼同工酶的研究

本实验采用聚丙烯酰胺垂直平板电泳方法,分析了大鳞鲃鱼的肝、肾、眼3种组织中的醋酶（EST）、淀粉酶（AMY）、乳脱酸氢酶（LDH）和苹果酸脱氢酶（MDH）4种同工酶。结果表明各种同工酶具有明显的组织特异性,肝脏酶活性最高,具有所有酶带。     

大鳞鲃人工繁育试验报告

从乌兹别克斯坦引进体质量20~40g的野生大鳞鲃(Barbus capito)鱼种,经5年人工培育性腺已发育成熟,2008年5月筛选8尾亲鱼进行人工繁殖试验。结果表明:注射催产药物LHRH-A2、HCG和DOM可促使亲鱼产卵和排精,催产的4尾雌鱼中有3尾成功产卵,获得受精卵4.8万粒,孵出鱼苗3万尾,其催产率、受精率、孵化率分别为75%,72.3%,67.1%。水温20~23℃时,从受精卵到孵出鱼苗需要约70h,到仔鱼上浮开口需要约6d。在哈尔滨地区池塘人工培育大鳞鲃鱼苗,1龄鱼体质量可达(40.06±1.19)g,体长(14.34±0.15)cm。     

碱度驯化对大鳞鲃幼鱼血液生理生化及肝脏抗氧化系统的影响

为了从血液生理生化、肝脏抗氧化应激等方面研究大鳞鲃(Luciobarbus capito)对碱度驯化的生理适应性变化,选择体重为(13.66±1.26) g的大鳞鲃幼鱼开展NaHCO3碱度适应性驯化实验,空白组一直处于淡水中养殖,驯化组经20 mmol/L的碱度适应性驯养7 d后再放入40 mmol/L的碱度水体中,未驯化组直接放入40 mmol/L的碱度水体中,测定并比较了鱼体放入40 mmol/L碱度水体中第0 h、6 h、12 h、24 h、48 h、96 h、7 d幼鱼血液生理生化指标和肝组织抗氧化系统相关指标变化。结果显示,驯化组和未驯化组鱼体的血液渗透压、白细胞、淋巴细胞、中性粒细胞、单核细胞、血红蛋白、红细胞、血小板、尿素、白蛋白含量和血小板压积等生理生化指标以及肝组织抗氧化系统中的超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GSH-Px)和丙二醛(MDA)在0 h~7 d的碱度胁迫过程中,均表现为先升高后降低的变化趋势(P<0.05),且驯化组峰值大小均显著性低于未驯化组(P<0.05),空白组在此期间均未表现出显著性变化(P>0.05)。驯化组鱼的血常规指标参数和肝脏组织的SOD、CAT出现峰值的时间均晚于未驯化组。驯化组鱼体在高碱度胁迫第7天时,其血液中的尿素浓度、淋巴细胞、单核细胞、血红蛋白、红细胞、血小板、白蛋白含量、谷草转氨酶(AST)、谷丙转氨酶(ALT)以及肝组织中的SOD、CAT、GSH-Px、MDA参数均显著性低于未驯化组(P<0.05)。研究表明,大鳞鲃幼鱼经过一定程度的碱度驯化后,在遭受更高碱度的水环境胁迫时,从生理层面反映出机体具有更强的适应性。     

大鳞鲃亲鱼培育及人工繁殖技术

邯郸市曲周东湖水产良种养殖场从黑龙江引进大鳞鲃(Barbus capito)后备亲鱼768尾,尾重1.8kg。经过3年的人工培育,亲鱼性腺已发育成熟,2015年筛选12条亲鱼进行人工繁殖试验,催产雌鱼5条,尾重3.9~4.1kg,雄鱼7条,尾重2.41kg。人工催产获得受精卵112万粒,受精率达67%,表明大鳞鲃亲鱼的培育已在当地获得成功。     

两种方法分析大鳞鲃染色体核型的比较研究

染色体核型分析是细胞遗传学研究的主要内容。为了获得准确、便捷的染色体核型分析方法,以引进耐盐碱品种大鳞鲃为实验材料,取头肾细胞冷滴片法制备染色体标本,采用E-ruler测量软件和Photoshop图像软件结合完成了染色体核型分析,并与常规方法的测量结果、核型分析进行了比较。结果显示,E-ruler软件与常规方法对伸展平直染色体的测量无显著差异,前者对弯曲形态染色体的测量结果更为准确;Photoshop图像软件能剔除染色体中期分裂相照片的背景,准确判断着丝粒的位置,快速、便捷地完成染色体核型图拼贴。研究表明,利用E-ruler软件和Photoshop软件相结合可获得准确、清晰的核型分析结果,本方法适用于其他鱼类和生物的染色体核型分析。染色体分析结果显示,大鳞鲃的染色体组为二倍体,未发现与性别有关的异型染色体,核型公式为2n=100=12m+38sm+38st+12t,NF=150。同鲃科其他鱼类的核型相比,大鳞鲃与国内几种倒刺鲃核型类似,具有鲃亚科进化核型特征。     

NaCl盐度和NaHCO3碱度对大鳞鲃幼鱼生长及鳃组织特征的影响

在水温22~25℃的条件下,研究不同盐度、碱度水体对大鳞(Barbus capito)幼鱼生长、摄食和鳃组织的影鲃响,探索了幼鱼生长的最适条件.单因素盐度梯度值设置为0(对照组)、2.0、4.0、6.1、7.8、10.0和11.9,实验结果表明,当盐度高于6.1时,大鳞幼鱼的体长和体质量受到显著影响(P<0.05);盐度2.0时幼鱼的终末体质量值最鲃大;盐度4.0时体质量特定增长率和饵料转化效率最高,盐度11.9时均降至最低;盐度到达7.8时对幼鱼生长有抑制作用,依据理论公式推算,幼鱼的最适生长盐度应为1.88.单因素碱度梯度值为10.00、15.83、25.10、39.80和63.12 mmol/L,碱度高于25.10 mmol/L时对幼鱼的体质量、饵料转化效率及总摄食量均有显著影响(P<0.05);碱度15.83 mmol/L时幼鱼的终末体质量、体质量生长率和饵料转化效率值最高,碱度63.12 mmol/L时最低.碱度到达39.80 mmol/L时对幼鱼生长有抑制作用,依据理论公式推算,幼鱼的最适生长碱度为20.57 mmol/L.从鳃组织的显微结构观察结果来看,随着盐度和碱度的升高,鳃小片上皮细胞出现肿胀、脱落和坏死的现象,泌氯细胞的体积膨胀,从而影响了幼鱼的生长.综上所述,大鳞幼鱼期,养殖盐度不宜超过6.1,碱度不超过25.10 mmol/L.鲃     

大鳞鲃消化系统早期发育的组织学观察

采用石蜡切片和显微观察的方法对由初孵仔鱼至23日龄的大鳞鲃消化系统发育进行了研究。初孵大鳞鲃仔鱼卵黄囊呈圆球形,消化道位于卵黄囊上方并伸展至卵黄囊后部,由柱状上皮细胞所组成,大部分为细胞索。2日龄时,口裂形成,口咽腔向鱼体后部进一步延伸。4日龄时,大鳞鲃的消化道由口至肛门全部打通,消化道分化为口咽腔、食道、前肠和后肠四部分。5日龄时,整个食道形成黏膜层,杯状细胞迅速增多,开始形成纵向褶皱。7日龄时,肝脏和胰脏的基本结构形成,并在肝脏和胰脏之间出现由单层柱状细胞围成的胆囊。10日龄时,卵黄囊消失,大鳞鲃完全通过摄取外界食物获取营养。10日龄—14日龄,消化道长度增长,褶皱加深,吸收表面积增加。14日龄后,通过大量摄食外源食物,大鳞鲃的体长迅速增大。     

尼罗罗非鱼幼鱼饲料的适宜脂肪需要

选用初始体质量为(46.14±4.67)g的尼罗罗非鱼(Oreochromis nilotica)360尾,随机分成6组(每组4重复,每重复15尾),分别饲喂添加鱼油水平为0%(对照组)、3%、6%、9%、12%和15%的纯化饲料(实测脂肪水平为0.20%、2.70%、6.11%、8.04%、11.13%和14.85%)。饲养8周后,以尼罗罗非鱼幼鱼的生长、体组成、血清生化及脂肪代谢酶活性等指标为判断依据,确定其饲料的脂肪需要量。结果表明,随饲料脂肪水平的升高,尼罗罗非鱼的增重率、特定生长率以及蛋白质效率均呈现先上升后下降的趋势,饲料系数呈现先下降后上升的趋势。饲料脂肪水平的升高使尼罗罗非鱼肝体比及全鱼和肌肉的脂肪含量显著增加(P<0.05)。随饲料脂肪水平的升高,尼罗罗非鱼血清总胆固醇和甘油三酯含量呈先上升后下降的趋势,各实验组显著高于对照组(P<0.05);血清高密度脂蛋白含量呈先上升后稳定的趋势;血清谷丙转氨酶和谷草转氨酶活性均在饲料脂肪水平为6.11%时最小,在14.85%时达到最大。随饲料脂肪水平的升高,尼罗罗非鱼脂蛋白酯酶、肝脂酶和肠道脂肪酶活性均呈先升高后下降的趋势,脂肪酸合成酶活性显著下降(P<0.05)。对增重率、蛋白质效率、饲料系数和血清高密度脂蛋白胆固醇进行回归分析得出,尼罗罗非鱼幼鱼饲料最适脂肪水平分别为8.86%,9.75%,9.40%和8.30%,因此确定尼罗罗非鱼幼鱼饲料适宜的脂肪需要量为8.30%～9.75%。     

卵形鲳鳗幼鱼蛋白质需要量的研究

为确定卯形鲳鳆（Trachinotus ovatus）幼鱼的蛋白需求量,进行为期8周的摄食生长试验。以鱼粉和豆粕为蛋白源设计6种试验饲料,蛋白质梯度分别为30．32％、35．56％、41．48％、47．86％、51．70％和54．70％。养殖试验在海水网箱中进行,每种饲料投喂3个网箱（1．5m×1．0m×2．0m）,每个网箱放养初始体质量（24．39±0．23）g的卵形鲳鲣30尾。试验结果表明,饲料蛋白水平对卵形鲳够特定生长率（SGR）及饲料效率（FER）有显著影响。随着饲料蛋白水平的升高,试验鱼SGR及FER均显著增加（P〈0．05）,而饲料蛋白水平高于41．38％时,各组无显著差异。饲料蛋白水平为47．86％组的卯形鲳够获得最好的SGR和FER。随着饲料蛋白水平升高,卵形鲳鳢鱼体蛋白质量分数也显著增加（P〈0．05）。根据折线模型确定卵形鲳够适宜的蛋白质需要量为45．75％。     

Optimal dietary methionine requirement of juvenile Chinese sucker,Myxocyprinus asiaticus

A total of 630 juvenile Chinese sucker, with an average initial weight of 1.72 ± 0.05 g, were fed seven diets for 56 days to study the effect of dietary methionine levels on growth, feed utilization, body composition and haematological parameters on juvenile Chinese sucker. Diet 1 using fish meal as the sole protein source and diets 2–7 using fish meal and fermented soybean meal as intact protein sources supplemented with crystalline amino acids contained six levels of l ‐methionine ranging from 6.4 to 18.9 g kg^?1 of dry diet at a constant dietary cystine level of 3.7 g kg^?1. Each diet was randomly assigned to three aquaria. Results indicated that the highest weight gain, specific growth rate (SGR), feed efficiency ratio, protein efficiency ratio and protein productive value occurred at 13.9 g methionine kg^?1 diet among the methionine supplemented dietary groups, beyond which they showed declining tendency. The whole body and muscle protein contents of juvenile Chinese sucker were positively correlated with dietary methionine level, while muscle lipid content was negatively correlated with it. The total essential amino acids content of muscle was increased significantly with increasing dietary methionine level from 6.4 to 13.9 g kg^?1 (P < 0.05). Apparent digestibility coefficients of dietary protein were significantly affected by dietary treatments. Serum protein, cholesterol and triacylglycerol increased with increasing dietary methionine levels, but showed a relatively lower value for fish fed the 18.9 g methionine kg^?1 diet. Quadratic regression analysis of SGR against dietary methionine level indicated that optimal dietary methionine requirement for juvenile Chinese sucker was 14.1 g kg^?1 of the diet in the presence of 3.7 g kg^?1 cystine (corresponding to 32.0 g kg^?1 of dietary protein on a dry‐weight basis).     

花幼鱼饲料中脂肪水平适宜量的研究

以等量混合的鱼油、豆油作为添加的脂肪源,设计成脂肪水平为1.62%、3.71%、5.77%、7.96%、9.95%和12.01%的6种饲料进行60 d养殖对比试验研究了饲料中花(Hem ibarbus maculatus)幼鱼脂肪水平适宜量。结果显示:花幼鱼饲料中不同脂肪水平对花的相对增重率、饲料系数和蛋白质效率存在显著差异(P<0.05),其中以投喂脂肪水平为7.96%的饲料花的生长最快,相对增重率为(1066.35±13.15)%;以投喂脂肪水平为5.77%的饲料花对蛋白质利用最高,蛋白质效率为(1.84±0.10);以投喂脂肪水平为5.77%的饲料花对饲料的利用最好,饲料系数仅1.39。研究结果表明:花幼鱼饲料中脂肪含量以5.77%~7.96%为最佳,考虑到饲料成本,把花幼鱼饲料脂肪的最适含量定为6%~7%。     

吉富罗非鱼对饲料亚油酸的需要量

选用初始体重为(60.98±3.82)g的吉富罗非鱼(Oreochromis niloticus)630尾,随机分成7组(每组设3个重复,每个重复30尾),饲喂亚油酸含量分别为0.07%(对照组)、0.36%、0.61%、1.03%、2.00%、3.00%和4.15%的7种半纯化等能等氮饲料10周。结果表明,鱼体增重率、饲料效率、蛋白质效率和蛋白质沉积率均在亚油酸水平为1.03%时较对照组差异显著(P0.05),且均在饲料亚油酸水平为2.00%时达到最大。经二次回归分析,饲料亚油酸水平为2.49%和2.66%时吉富罗非鱼分别获得最大增重率和最高饲料效率。通过折线回归发现饲料亚油酸水平为1.02%时,吉富罗非鱼获得最大蛋白沉积。肝体比和脏体比均随亚油酸水平的升高而升高,当饲料亚油酸含量为0.61%~4.15%时显著高于对照组(P0.05)。亚油酸添加组的肌肉粗脂肪含量显著高于对照组(P0.05);当饲料亚油酸含量为1.03%~4.15%时,肝和全鱼粗脂肪含量显著高于对照组(P0.05)。随饲料亚油酸水平升高,血清甘油三酯和总胆固醇变化趋势一致,呈现先下降后上升的趋势,经二次回归分析亚油酸水平为1.63%时血清甘油三酯含量最低;各亚油酸添加组的血清高密度脂蛋白胆固醇含量显著高于对照组,且在饲料亚油酸含量为1.13%时达到最大(P0.05);当饲料亚油酸水平为1.03%~4.15%时,血清低密度脂蛋白胆固醇含量显著低于对照组(P0.05)。随饲料中饱和脂肪酸(∑SFA)含量下降,吉富罗非鱼肌肉和肝脏∑SFA含量均呈下降的趋势;随饲料亚油酸水平增加,肌肉和肝脏的n-6多不饱和脂肪酸(∑n-6 PUFA)含量呈上升趋势,肌肉和肝脏的∑n-3 PUFA含量呈下降趋势。综上所述,初始体重为(60.98±3.82)g的吉富罗非鱼饲料亚油酸需要量为1.02%~2.66%。     

Optimal dietary protein requirement for juvenile ivory shell, Babylonia areolate

A growth experiment was conducted to determine the optimal dietary protein requirement for juvenile ivory shell reared in indoor aerated aquaria. Six isoenergetic experimental diets using fish meal, casein and gelatin as protein sources were formulated to contain graded levels of protein (27, 33, 38, 43, 49 and 54% of dry diet, respectively). Triplicate groups of 40 shells (average weight 93.50 ± 1.70 mg) were stocked in 120-l tanks and fed to apparent satiation twice daily for 8 weeks. The results showed that the growth performance and feed utilization were significantly affected by dietary protein level (P < 0.05). Maximum weight gain, mean protein gain, specific growth rate and soft body to shell ratio occurred at 43% dietary protein level (P < 0.05). There were significant differences in protein, lipid, moisture and ash content in soft body; except that ash content in shell was not significantly affected by dietary protein level. Pepsin activity in soft body tissue significantly increased with dietary protein level up to 43%, and trypsin-like enzyme activity increased with dietary protein level up to 49%. However, lipase activity in soft body decreased with increasing dietary protein level. However, no significant differences (P < 0.05) in survival, calcium, phosphorus concentration in the shell and soft body were found among dietary treatments. Quadratic regression analysis of weight gain against dietary protein level indicated that the optimal dietary protein requirement for maximum growth and feed utilization of juvenile ivory shell is 45% of dry diet.     

草鱼幼鱼对烟酸的需要量

草鱼幼鱼的初始体重为(12.43±0.80) g,试验分为7组,其饲料中烟酸含量分别为5.1、9.8、16.6、32.2、66.7、130.1、271.5 mg·kg-1,每组设3个重复,每桶30尾鱼,日投喂率2%～3%,饲养试验周期为8周.研究不同含量烟酸对草鱼幼鱼生长性能、饲料系数、机体营养组分、造血功能及血脂的影响,以确定草鱼幼鱼饲料中适宜烟酸需要量.试验结果表明:①添加烟酸显著提高了特定生长率、增重率和草鱼幼鱼的存活率,对草鱼幼鱼肥满度无显著影响;烟酸含量为32.2 mg·kg-1时草鱼的特定生长率和增重率最大,饲料系数最低,并与其它各组存在显著差异;②添加烟酸对草鱼全鱼水分、灰分无显著影响,显著提高了全鱼粗脂肪含量,但各添加组间无显著差异,饲料中烟酸含量为66.7 mg·kg-1时,全鱼粗蛋白含量显著高于对照组及9.8 mg·kg-1组;③添加烟酸显著提高了血液红细胞计数和血红蛋白含量,但对血清胆固醇和甘油三酯无显著影响,烟酸含量为16.6 mg·kg-1及以上时显著提高血清高密度脂蛋白胆固醇与低密度脂蛋白胆固醇,与对照组和9.8 mg·kg-1组存在显著差异.基于折线法分析,草鱼幼鱼获得最佳生长时对饲料中烟酸的最低需求量为25.5 mg·kg-1.     

Optimal dietary carbohydrate to lipid ratio for juvenile yellowfin seabream (Sparus latus)

A growth experiment was conducted to determine the optimal carbohydrate‐to‐lipid (CHO: L) ratio for juvenile yellowfin seabream cultured in 340‐L indoor recirculating tanks. Seven isonitrogenous (450 g kg⁻¹ dietary protein) and isoenergetic (14.1 MJ kg⁻¹) diets with increasing CHO: L ratios (0.03–5.09 g: g) were fed to triplicate groups of 30 fish with an initial weight of 4.91 g for 56 days. Fish were fed to satiation twice a day and the water temperature ranged between 28 and 31.7 °C during the experimental period. Survival was high in all the groups and was not affected by dietary treatments. Best weight gain (WG) and specific growth rate (SGR) were observed in fish fed diets with CHO: L ratios of 0.29 and 0.72, which were not significantly different from that of 0.03, 1.26 and 1.92, but apparently higher than that of 3.22 and 5.09. Feed efficiency (FE), protein efficiency ratio (PER) and protein production value (PPV) followed the same general pattern as WG and SGR. Highest level of energy production value (EPV) was found in fish fed diets with CHO: L ratio of 0.72. Proximate compositions of fish whole body and tissues were markedly affected by dietary CHO: L ratios. Whole body, muscle and liver lipid increased as CHO: L ratios decreased, whereas moisture contents were reduced. Dietary CHO: L ratios had no significant effect on protein content in whole body and muscle. Plasma total cholesterol levels of fish fed diets with CHO: L ratios less than 0.72 were significantly higher than those of the other groups. Triacylglyceride levels decreased linearly as dietary CHO: L ratios increased. Viscerosomatic index (VSI) significantly increased as dietary CHO: L ratios decreased. Intraperitoneal fat ratio (IPF) of fish fed diets with CHO: L ratios less than 1.92 were significantly higher than those fed CHO: L ratios of 3.22 and 5.09. Hepatosomatic index (HSI) did not vary between the test diets. Based on second‐order polynomial regression analysis of WG against dietary carbohydrate and lipid levels, 84.1 g kg⁻¹ of carbohydrate and 136.3 g kg⁻¹ of lipid, corresponding to a CHO: L ratio of 0.62, in a diet holding 450 g kg⁻¹ of crude protein and 14 KJ g⁻¹ of metabolizable energy, proved to be optimal for juvenile yellowfin seabream.