复合蛋白替代鱼粉对花鲈生长、消化能力和肠道健康的影响

以初均重为(5.80±0.07) g的花鲈(Lateolabrax maculatus)幼鱼为实验对象,研究复合蛋白替代鱼粉对花鲈生长、消化和肠道健康的影响。用复合蛋白分别替代对照组饲料中0、20%、40%、60%和80%的鱼粉,配制成5种等氮等脂的实验饲料,分别用这5种饲料投喂花鲈70 d;养殖实验期间水温为(29.5±1.5)℃,盐度为29±1,溶解氧≥6.5 mg/L。养殖实验结束后采集样品进行分析,结果显示,20%替代组花鲈生长性能与对照组无显著差异(P>0.05),但随鱼粉替代比例的升高,花鲈增重率(WGR)、存活率(SR)、饲料效率(FE)以及蛋白质效率(PER)显著下降(P<0.05),花鲈肠道蛋白酶活性以及饲料干物质、粗蛋白与粗脂肪表观消化率皆显著降低(P<0.05),且花鲈后肠黏膜组织结构出现损伤,肠道促炎因子TNF-α、IL-1β基因表达量升高,抗炎因子基因IL-4、IL-10表达量相应降低。研究表明,复合蛋白替代花鲈饲料中鱼粉比例不宜超过20%。     

四纹豆象及其近缘种基于COI基因的分子检测技术研究

四纹豆象是口岸检疫中经常截获的种类,本文以四纹豆象及其近缘种为研究对象,测定分析了COI基因516 bp碱基序列。序列分析结果表明:保守位点为353个,变异位点为163个,简约信息位点为134个,自裔位点为29个。基于Kimura 2-parameter模型分析遗传距离,结果显示:种内遗传距离介于0.001~0.013之间,平均遗传距离为0.008,种间遗传距离介于0.114~0.193,平均遗传距离为0.161。采用邻接法构建的COI基因序列系统发育树显示,同一物种聚为同一小支,且分支自展值均为100%。结果表明应用COI基因片段对四纹豆象及其近缘种进行分子鉴定具有可行性。     

绿豆象在不同豆类上的生长发育及产卵选择性研究

在室内25℃恒温条件下,饲养观察了绿豆象[Callosobruchus chinensis(Linn.)]对不同豆种的产卵选择性、产卵量、卵的孵化率、幼虫和成虫的生长发育历期。结果表明,供试的17种豆粒上绿豆象的着卵率均达80%以上,且不同豆种粒上产卵量差异显著(P0.01),卵在不同豆种上的孵化率间也存在显著差异(P0.05),卵孵化后,幼虫仅在蚕豆、绿豆、红皮豇豆、豌豆、黑豆、红小豆、大豆上可蛀入危害,蛀孔数分别为3.00±0.25,2.00±0.18,3.50±0.09,2.50±0.21,4.50±0.10,2.00±0.22,2.50±0.17蛀孔/豆,差异显著(P0.05)。在蚕豆、绿豆、红小豆、红皮豇豆、黑豆、大豆粒上的世代存活率分别为(0.63±0.12)%,(54.84±0.09)%,(44.40±0.08)%,(46.33±0.11)%,(66.88±0.10)%,(45.71±0.11)%,(21.59±0.21)%;雌虫的产卵期分别为(4.24±1.58)d,(5.10±0.22)d,(5.40±0.26)d,(5.21±1.25)d,(5.30±0.38)d,(4.63±0.41)d和(4.30±0.80)d,差异不显著(P0.05),卵历期分别为(5.01±0.15)d,(4.30±0.05)d,(4.10±0.08)d,(5.10±0.18)d,(4.30±0.07)d,(4.20±0.14)d及(4.51±0.16)d,差异不显著(P0.05);幼虫的平均历期分别为(33.40±4.85)d,(31.60±1.78)d,(28.22±3.56)d,(30.91±2.49)d,(27.30±1.98)d,(29.50±1.93)d及(36.70±4.97)d,差异显著(P0.05)。不同豆种上绿豆象雄虫寿命间差异不显著(P0.05),而雌虫寿命差异显著(P0.05)。     

袁河花(鱼骨)形态生物学研究

[目的]为袁河花(鱼骨)形态种质资料提供基础生物学资料.[方法]以花(鱼骨)群体为研究对象,测量了140尾袁河花(鱼骨)的外部形态特征.[结果]袁河花(鱼骨)全长为体长的(1.21±0.0236)倍,体长为体高的(4.78±1.4965)倍、为头长的(3.76±0.2035)倍、为尾柄长的(6.68±1.0324)倍,头长为吻长的(2.80±0.3021)倍、为眼径的(4.01±0.3939)倍、为眼间距的(3.21±1.1515)倍,为头宽的(2.10±0.3075)倍,为头高的(1.81±0.1484)倍,为口裂宽的(4.44±0.6499)倍,尾柄长为尾柄高的(1.68±0.2866)倍.体重与体长的相关式为W=0.0224L29168(R2=0.9576).肥满度系数(K)为1.57±0.1908,空壳重与体重比值(V)为0.87士0.0572,花(鱼骨)肠道系数(Ci)为1.08±0.1261,体长与肠长呈线性关系,其相关方程为:Y=1.2624X-2.8109(r2 =0.7934).除内脏重、性腺重、成熟系数外,雌雄个体其他外形参数无显著差异(P＞0.05).[结论]袁河花(鱼骨)呈负异速生长.     

2种鞘翅目仓储害虫触角的显微结构研究

利用扫描电镜技术对仓储害虫白腹皮蠹(Dermestes maculatus Degeer)和拟白腹皮蠹(D.fris-chii kugelann)触角感器进行了比较观察研究。结果表明:2种害虫的触角均由柄节、梗节和鞭节3部分组成,共11节。2种蠹虫均观察到4类7种感器,为毛形感受器(ST)、刺形感器Ⅰ、刺形感器Ⅱ、刺形感器Ⅲ、锥形感器Ⅰ、锥形感器Ⅱ、B?hm氏鬃毛;通过比较2种蠹虫的触角感器,讨论了其可能的功能及在分类学中的应用。     

花(鱼骨)的两性异形和雌体繁殖输出

测定了花成体的两性异形和雌体繁殖输出。结果表明,两性成体的体长差异不显著。特定体长的怀卵雌性个体的体高显著大于产后雌体和成年雄体,产后雌体的头宽、头高、尾柄长、尾柄高大于怀卵雌性和成年雄性,产后雌体的尾鳍长、腹鳍臀鳍间距则相对较小,其它局部形态特征不存在显著的两性差异。主成分分析(Eigenvalue≥1)发现,前三个主成分共解释57.7%的变异。头长、腹鳍基前距在第一主成分有较高的正负载系数,头宽、尾柄长、尾柄高在第二主成分有较高的正负载系数,眼间距在第三主成分有较高的正负载系数。第一和第二主成分分值的组间差异显著,第三主成分分值组间差异不显著。花雌体通过个体大小的增加和腹部形态的改变增加繁殖输出。     

花对饲料中3种不同无机磷源的利用率

在以鱼粉和豆粕为蛋白源的基础饲料中分别添加磷酸二氢钙(MCP)、磷酸氢钙(DCP)、磷酸钙(TCP)制成总磷含量为0.91%的饲用饲料,饲养11g左右的花(Hemibarbus maculatus Bleeker)8周,研究了饲料中不同磷源对花幼鱼的生长,全鱼、脊椎骨和鳞片的灰分、钙、磷含量,以及总磷表观消化率的影响。结果表明,不同无机磷源对花的增重率、饲料效率有显著影响(P<0.05),MCP组、DCP组的相对增重率分别比TCP组提高24.86%和13.75%,MCP组的饲料效率比TCP组提高15.47%;MCP、DCP、TCP组全鱼、脊椎骨及鳞片的灰分、磷含量差异显著(P<0.05),MCP组全鱼、脊椎骨及鳞片的灰分、磷含量最高,显著高于TCP组,各组全鱼、鳞片的钙含量无显著差异;花对不同磷源的总磷表观消化率存在显著差异(P<0.05),MCP的表观消化率最高,MCP组、DCP组总磷表观消化率比TCP组分别提高85.97%和42.90%。综合来看,在3种无机磷源中,MCP作为花饲料中无机磷源的利用效果最佳,其次是DCP,而TCP则效果相对较差。     

Characterization of whitebait (Galaxias maculatus) respiratory rates to optimize intensive culture carrying capacities

Galaxias maculatus is an osmeriform native fish of the Southern Hemisphere, in which the crystalline larvae is considered as a luxury delicacy, for this reason, it has been commercially exploited in Chile, Argentina and New Zealand. However, the fisheries have been rapidly decreasing due to the overexploitation and the predation of introduced species. Because of these events, there is a need to determine a carrying capacity for an intensive fish culture. In order to optimize stocking densities for fish culture, this paper proposes objectives to determine oxygen consumption (OC) rates, dissolved oxygen concentrations that produce signs of hypoxia and the average time elapsed between food intake and peak OC in G. maculatus. In the oxygen experiments under routine metabolism conditions, we found that G. maculatus adults and whitebait showed signs of asphyxia at dissolved oxygen concentrations between 1.3 and 2.2 mg L^?1 and that adults tolerated dissolved oxygen levels as low as 1.3 mg L^?1. The results showed that G. maculatus individuals with an average weight of 0.04 g consumed 0.048 mg O₂ h^?1, whereas individuals with an average weight of 1.4 g consumed 0.345 mg O₂ h^?1. Galaxias maculatus increased the OC rate by 31%, from 0.39 to 0.51 mg O₂ h^?1 g^?1, occurring 14 min after food intake. The carrying capacities for industrial cultures of G. maculatus, were estimated using an allometric equation (OC=0.2363 ×W ^0.612 ), a water flow rate of 1 m³ h^?1 and an input oxygen concentration of 10 mg L^?1 at 12 °C. The density culture of whitebait (4 g) can be allowed to reach 8–11 kg m^?3; therefore, these stocking densities reduce the risk of hypoxia and mortality, ensuring the appropriate growth and feed conversion rates.     

花鲈对七种蛋白质原料的表观消化率

为了解花鲈(Lateolabrax maculatus)对水解羽毛粉、喷雾干燥血球蛋白粉、鸡肉粉、黄粉虫粉、大豆分离蛋白、大豆浓缩蛋白和脱酚棉籽蛋白等七种蛋白质原料的干物质、钙、磷、粗蛋白和氨基酸的表观消化率,实验选取平均体重为(54.3±1.5)g的花鲈240尾,随机分成8组,每组3个平行,对照组投喂基础饲料,试验组分别投喂试验饲料,试验饲料由70%基础饲料和30%实验原料组成,以0.1%的三氧化二钇(Y2O3)为外源指示剂。结果显示:花鲈对七种蛋白质原料的干物质和粗蛋白表观消化率以血球蛋白粉、鸡肉粉、大豆分离蛋白和大豆浓缩蛋白较高,脱酚棉籽蛋白和黄粉虫粉次之,水解羽毛粉最低。其中,花鲈对血球蛋白粉的粗蛋白消化率最高,为95.64%,显著高于其他六种原料;鸡肉粉次之,为90.61%,与大豆分离蛋白和大豆浓缩蛋白之间差异不显著;水解羽毛粉最低,为71.18%,与黄粉虫粉和脱酚棉籽蛋白之间差异不显著,与其他蛋白原料之间差异显著。花鲈对鸡肉粉和黄粉虫粉的总钙的表观消化率分别为30.39%和42.65%。花鲈对总磷的表观消化率从高到低依次为大豆分离蛋白(76.04%)、脱酚棉籽蛋白(67.49%)、大豆浓缩蛋白(51.24%)、鸡肉粉(42.88%)、黄粉虫粉(38.40%)。花鲈对各蛋白质原料中氨基酸的表观消化率与粗蛋白质的表观消化率变化趋势基本一致。结果表明,喷雾干燥血球蛋白粉、鸡肉粉、大豆分离蛋白和大豆浓缩蛋白可作为花鲈优质的蛋白源,脱酚棉籽蛋白、黄粉虫粉和水解羽毛粉在花鲈饲料中添加量不宜过高。     

Effect of EPA/DHA ratios on the growth and survival of Galaxias maculatus (Jenyns, 1842) larvae reared under different salinity regimes

Despite the importance of certain highly unsaturated fatty acids in osmotic regulation, few studies have been addressed to determine the essential fatty acid requirements for a given species cultured under different salinities. As Galaxias maculatus is a diadromic species, the present study aimed to determine the effect of salinity on the optimum dietary EPA/docosahexaenoic (DHA) ratio for survival and growth during the larval stages. Larvae were fed for 20 days with rotifers containing two different EPA/DHA ratios (low: 0.64 and high: 2.18) at three different salinities (0, 10 and 15 g L^?1). The results of this study showed a marked effect of water salinity on larval dietary lipid utilization in G. maculatus larvae. These results suggested that G. maculatus larvae reared at higher salinities may have a higher dietary requirement for DHA, whereas larvae reared at 0‰ showed higher requirements for EPA. The overall results of the present study indicate that even small changes in salinity can determine the optimum dietary EPA/DHA ratio and the quantitative essential fatty requirements of fish. This may have important repercussions and affect the rearing performance of G. maculatus cultured under different salinities.