不同成熟期茄子品种对侧多食跗线螨抗性研究

以田间种群密度作抗性指标对不同成熟期茄子品种抗侧多食跗线螨（Polyphago-tarsonemus latus(Banks）进行差异分析研究，结果表明不同成熟期茄子品种对侧多食跗线螨的抗性差异不显著。     

花鲈保鲜技术的研究进展

花鲈是中国最为重要的经济鱼类之一:产量高,收益好,味道鲜,深受全国消费者的喜爱。花鲈营养丰富,富含蛋白、多不饱和脂肪酸和微量元素,也正因此容易腐败变质。故运用恰当的保鲜技术,延长其货架期同时保留营养和风味非常重要。通过对花鲈保鲜的大量研究进行整理和归纳,以期为花鲈保鲜技术的研究提供参考。至今为止,花鲈的保鲜技术主要为辐照和超高压处理、低温贮藏、保鲜剂使用、包装技术、组合保鲜等。花鲈贮藏之前,辐照杀菌效果显著,且因对花鲈的感官品质影响较小,故保鲜效果优于超高压处理;贮藏期间,微冻比冻藏节能且比冷藏的保鲜效果好,是个较好选择。对于运输过程中的温度变化,保鲜剂的使用能很好地抑制温度变化对花鲈品质造成的损害,同时减少低温保鲜的能耗成本。保鲜剂的发展趋势是生物保鲜剂及其复合使用。充气包装和活性包装在维持花鲈的新鲜度方面也有显著效果,值得进行更多研究开发。花鲈的保鲜技术将会是多种技术组合使用,最终兼具高效、安全、经济的特性。     

高体革鯻、鲈和鳜的营养成分分析比较

对高体革、鲈和鳜肌肉及内脏中的一般营养成分(水分、灰分、粗蛋白和粗脂肪)及脂肪酸和氨基酸组成进行了分析比较。结果表明:高体革内脏占鱼体重的32.90%,而其中脂肪含量高达87.06%;高体革肌肉及内脏中的水分、灰分和蛋白质含量都比鲈、鳜低,而脂肪含量明显高于鲈和鳜;对3种鱼的脂肪酸组成进行分析,共确定19种脂肪酸,其中20∶5ω3(EPA)和22∶6ω3(DHA)总量占鱼内脏比例最高的是高体革,达4.115%;高体革、鲈和鳜肌肉中的必需氨基酸占氨基酸总量最高的为高体革,达42.18%,氨基酸分(AAS)分别为116、75和73。     

花鲈瘦素基因的克隆及低盐度条件下调控表达分析

瘦素(Leptin,Lep)在动物摄食、生长、生殖、免疫、能量平衡等方面具有重要作用,为研究花鲈Lateolabrax maculatus Lep功能,采用c DNA末端快速扩增法(RACE)克隆花鲈Lep A c DNA全长序列。急性低盐度调控试验设置海水组(盐度32)、半海水组(盐度16)和淡水组(盐度0),盐度调控24、48、96、144、192 h后测定花鲈肝脏中Lep A mRNA的表达情况。结果表明:Lep A c DNA全长序列为643 bp,其中开放阅读框483 bp,编码161个氨基酸,其氨基酸序列由信号肽和A、B、C、D 4个α螺旋区域组成;花鲈Lep A氨基酸序列与其他物种同源性较低,但三级结构较为保守;花鲈Lep A主要在肝脏中表达,其次为脑;低盐调控48 h时,半海水组与淡水组Lep A表达无显著性差异(P0.05),但均显著低于海水组(P0.05),分别为海水组的33.38%和26.86%。研究表明,急性低盐度调控可降低花鲈Lep A表达水平。     

黄鳍鲷的池养生长特性及其饲养技术

研究了黄鳍鲷池养生长特性和饲养技术,单养黄鳍鲷的旺生长期Ⅰ龄,应用ｖｏｎＢｅｒｔａｌａｎｆｆｙ方程,求得人工饲养条件下其体长、体重生长方程为Ｌｔ＝２４８．１７５９「１－ｅ＾－１．０３１４（ｔ＋０．１４８３）」;Ｗｔ＝４６９．２９２６「１－ｅ＾－１．０３１４（ｔ＋０．１４８３）」＾２．８３０２。体重生长拐点于０．８６龄处。进行２８８．２ｈｍ＾２的河口近岸池塘单养和混养,单养周年平均单产７．３ｔ／ｈｍ     

Effects of dietary lipid levels on the growth, digestive enzyme, feed utilization and fatty acid composition of Japanese sea bass (Lateolabrax japonicus L.) reared in freshwater

Triplicate groups of 40 Japanese sea bass Lateolabrax japonicus reared in freshwater (average weight, 9.52±0.47 g) were fed with six isonitrogenous (∼46% crude protein) diets containing 6%, 8%, 10%, 12%, 14% or 16% lipid for 10 weeks respectively. The results showed that the maximum weight gain (WG), specific growth rate (SGR), feed intake (FI) and protein efficiency ratio (PER) all occurred at the 10% lipid level ( P <0.05) and growth depression occurred when the dietary lipid level was over 12%. Whole body and liver lipid concentrations were enhanced with the increase in the dietary lipid levels, but the muscle lipid content did not significantly change with the increase in the dietary lipid levels. Both liver pepsin and trypsin activities increased with dietary lipid levels ranging from 6% to 10%, and then decreased with a further increase in the dietary lipid content. Liver lipase activities showed a positive correlation with dietary lipid levels, but amylase activities were not markedly influenced by dietary lipid levels. High proportions of 18:1n-9, 20:1n-9, eicosapentaenoic acid (20:5n-3; EPA), 22:1n-11 and docosahexaenoic acid (22:6n-3; DHA), and low concentrations of n-6 fatty acids, particularly 18:2n-6 occurring in the liver and muscle, to some extent, reflected the fatty acid composition in experimental diets.     

海水养殖花鲈对几种饲料蛋白原料的表观消化率

测定了在室内海水流水系统中养殖的花鲈对7种常用饲料原料,宠物级鸡肉粉(P-PBM)、饲料级鸡肉粉(F-PBM)、血粉(BM)、羽毛粉(FEM)、蚕蛹粉(SWP)、豆粕(SBM)和菜粕(RSM)以及1种混合动物蛋白粉(MM=50%P-PBM+20%F-PBM+20%BM+10%FEM)的干物质、蛋白质和能量表观消化率(ADC)。实验饲料由70%基础饲料(蛋白质含量为42.0%,能量含量为18.9MJ/kg)和30%的待测原料组成。基础饲料和实验饲料中均添加1%(质量分数)的Cr2O3作为外源标记物。饲养实验共进行4周。实验期间每天投饵两次,采用虹吸方法收集粪便。实验结果显示:花鲈对P-PBM、F-PBM、BM、FEM、MM、SWP、SBM和RSM干物质ADC分别为61%～87%,蛋白质ADC为80%～96%,能量ADC为75%～93%。其中,花鲈对SBM的蛋白质ADC最高,对MM的蛋白质ADC最低,对BM的干物质和能量ADC最高,对RSM的干物质和能量ADC最低。     

Growth performance,digestive enzyme activity and immune response of Japanese sea bass,Lateolabrax japonicus fed with fructooligosaccharide

In this experiment, a feeding trial was performed to determine the effects of fructooligosaccharide (FOS) on growth performance, digestive enzyme activity and immune response of Japanese sea bass, Lateolabrax japonicus juveniles (initial weight 38.3 ± 0.5 g), and the fish were examined following feeding with six levels of FOS (0, 0.5, 1, 2, 4 and 6 g/kg) for 28 days. Significant enhancement of weight gain (WG) and specific growth rate (SGR) was found in fish fed 1 g/kg FOS incorporated diets (p < .05), while the feed conversion ratio (FCR) in the 1, 2 g/kg FOS groups reduced significantly compared with the control (p < .05). Besides, the crude lipid in the 4, 6 g/kg FOS groups increased significantly compared with the control (p < .05). On the other hand, the erepsin and lipase activities significantly elevated in intestine of fish fed 2 g/kg FOS (p < .05) and the lysozyme activity in serum of fish fed 2 g/kg FOS were significantly higher than that in the control (p < .05). Moreover, the alkaline phosphatase activities in serum of fish fed 0.5, 1, 2 g/kg FOS were significantly higher than in control (p < .05). Regression analysis showed that the relationships between dietary FOS levels and either SGR, FCR, erepsin or lysozyme activities were best expressed by regression equations, and the optimal inclusion levels are 1.37, 1.80, 3.06, 3.11, 1.93 and 1.80 g/kg for SGR, FCR, erepsin, lipase, lysozyme and total superoxide dismutase activities, respectively. Overall, this study revealed that FOS incorporated diets could beneficial for L. japonicus culture in terms of increasing the growth, digestion and immune activities. Under the present experimental condition, the optimal supplementary level of FOS in the diet of L. japonicus is 1–3 g/kg.     

花鲈冰藏过程中肌原纤维蛋白生化特性与新鲜度变化的相关性

为研究冰藏期间花鲈鱼片的品质及蛋白质生化特性的变化,通过感官评分、pH、质构、色差、硫代巴比妥酸值(TBA值)、挥发性盐基氮(TVB-N)值、菌落总数(TVC)和肌原纤维蛋白含量、巯基、羰基含量的测定及十二烷基硫酸钠—聚丙烯酰胺凝胶电泳(SDS-PAGE)确定了冰藏花鲈鱼片理化指标变化,并对肌原纤维蛋白生化特性与主要的...     

牛磺酸对花鲈生长性能、消化酶活性、抗氧化能力及免疫指标的影响

采用牛磺酸添加量分别为0(N0)、0.4%(N1)、0.8%(N2)、1.2%(N3)和1.6%(N4)的5组试验饲料,投喂均质量(7.2±0.07)g的花鲈(Lateolabrax maculatus)56 d,研究其对花鲈生长、消化酶活性、抗氧化能力及免疫指标的影响。结果显示,牛磺酸可提高花鲈的特定生长率、增重率和摄食率,其中N2、N3和N4组均显著大于对照组(P<0.05);牛磺酸可显著提高全鱼的粗蛋白含量并降低粗脂肪含量(P<0.05);牛磺酸可显著提高花鲈肠道蛋白酶和脂肪酶活性(P<0.05);牛磺酸添加组的红细胞和白细胞数均显著高于对照组(P<0.05),N2、N3和N4组的血红蛋白浓度显著高于对照组(P<0.05);牛磺酸添加组的溶菌酶活性、免疫球蛋白M(IgM)和补体4(C4)浓度显著高于对照组(P<0.05);牛磺酸可显著提高花鲈肝脏总抗氧化能力、过氧化氢酶、超氧化物歧化酶和谷胱甘肽过氧化物酶活性(P<0.05),显著降低丙二醛浓度(P<0.05)。线性回归分析结果表明,以增重率为目标,花鲈对牛磺酸的最适需求量为0.85%。