Influence of dietary phospholipids on early ontogenesis of fish

The aim of this paper is to provide explanations of how dietary phospholipid (PL) globally improves fish larval development, including growth and survival, digestive functions and skeletal development, and to propose optimal PL levels and sources in fish larval diets. Dietary incorporation of 8–12% PL related to dry matter (d.m.) promotes growth and enhanced survival in various species. Marine source PL, incorporating highly unsaturated fatty acids, was most efficient than soybean lecithin. This beneficial effect was explained by an enhancement in digestive functions, assessed by digestive enzyme activities and histomorphology. Nevertheless, 1.5–2.5% highly unsaturated fatty acids related to diet d.m. supplied by PL improved growth, survival and skeletal development, while 5% induced different skeletal deformities. The high incidence of deformities was associated with the down-regulation of genes involved in development, such as RXRα, RARα, RARβ and BMP-4, observed in the early stages in larvae fed a high highly unsaturated fatty acids level.     

岩原鲤肌肉营养成分分析

岩原鲤(Procypris rabaudi)蛋白质含量为19.60%,与鲤、草鱼相当,高于斑点叉尾鲴、斑鱯、中华倒刺鲃、鲫;其脂肪含量为1.80%,低于斑点叉尾鮰、斑鱯、草鱼,与中华倒刺钯相当,明显高于鲤、鲫;16种氨基酸含量为15.65 g/kg,较鲫低,比斑鳠、草鱼和鲤高,与中华倒刺鲃相当.5种鲜味氨基酸含量为5.85 g/ks.岩原鲤具有良好的开发利用前景.     

花鳗鲡的基础生物学研究

采用摄影技术和直接测量等方法对花鳗鲡的基础生物学进行研究。花鳗鲡的形态测定、内脏解剖、耗氧率及肌肉生化成分分析结果为:D-A/D-头后缘=1.465±0.028,为发育中的稳定形态比例性状,W=1.76×10-3L3.11;肠近中部有一个“V”型小弯曲;生殖腺出现时间明显晚于日本鳗鲡和欧洲鳗鲡;昼夜平均耗氧率为73.49 mg/kg.h;蛋白质、脂肪、水分含量百分比为11.44、5.08、77.94,氨基酸有18种,脂质以甘油三脂为主,无机元素、EPA和DHA含量高,DHA>EPA,营养价值优于日本鳗鲡和欧洲鳗鲡。     

罗氏沼虾诺达病毒单克隆抗体的制备及应用

罗氏沼虾肌肉白浊病（whitish muscle disease of Macrobrachium rosenbergii）是一种发生在罗氏沼虾苗种阶段的流行病,发病虾苗出现肌肉白浊、白斑或白尾症状,死亡率高达60％以上,作者所在实验室在确定其病原是罗氏沼虾诺达病毒（Macrobrachiium rosenbergii Nodavirus,MrNV）的基础上,用MrNV免疫BALB／c小鼠,取小鼠脾细胞与SP2／0鼠骨髓瘤细胞融合,用间接ELISA筛选阳性孔,经有限稀释法克隆,得到12株能特异分泌抗MrNV的单兜隆抗体（Mab）的杂交瘤细胞。注射小鼠,制备腹水单克隆抗体,ELISA效价为1：10^5～10^6。亚型鉴定结果表明,有6株单抗为IgG1型,4株甲抗为IgG2a型,2株单抗为IgG2b型。12株单抗与对虾白斑综合征病毒（WSSV）和桃拉综合征病毒（TSV）均无交叉反应：挑选效价高的腹水单抗2B5,建立了检测罗氏沼虾诺达病毒的三抗体夹心酶联免疫吸附测定（TAS—ELISA）法,该方法检测灵敏度达0．98ng左右。Wesrtem blot分析表明,2B5能与MrNV 43kD的外膜蛋白特异性结合。     

PSMB5蛋白对牛骨骼肌卫星细胞增殖与成肌分化的影响

【目的】探究蛋白酶体β5亚基（proteasome subunit beta type-5, PSMB5）对牛骨骼肌卫星细胞增殖与成肌分化的影响,为进一步研究蛋白酶体亚基PSMB5在细胞分化和肌肉发育过程中的调控作用提供依据。【方法】利用牛骨骼肌卫星细胞体外诱导成肌分化模型,模拟牛骨骼肌生长发育过程,首先检测牛骨骼肌卫星细胞分化前后PSMB5的表达变化,采用qRT-PCR法检测PSMB5在牛骨骼肌卫星细胞分化前后基因表达水平的差异,采用Western blotting 法检测PSMB5在牛骨骼肌卫星细胞分化前后蛋白表达水平的差异。然后设计合成PSMB5的小干扰RNA si-RNA-PSMB5（si-PSMB5）,构建PSMB5过表达质粒载体pcDNA3.1-PSMB5（pcDNA-PSMB5）,采用（Lipofectamine）3000转染试剂将si-PSMB5和pcDNA-PSMB5转染牛骨骼肌卫星细胞,qRT-PCR法及Western blotting法检测转染效果。最后采用EdU染色的方法检测干扰和过表达PSMB5对牛骨骼肌卫星增殖的影响;进一步对牛骨骼肌卫星细胞进行体外成肌诱导分化,光学显微镜观察牛骨骼肌卫星细胞肌管形成状态,Western blotting检测分化标志因子肌球蛋白重链（MyHC）蛋白水平的表达变化,分析干扰和过表达PSMB5对牛骨骼肌卫星细胞成肌分化的影响,综合分析PSMB5蛋白对牛骨骼肌卫星细胞增殖与成肌分化的影响。【结果】PSMB5在牛骨骼肌卫星细胞分化前后表达水平存在显著差异,牛骨骼肌卫星细胞诱导分化后PSMB5的mRNA和蛋白表达量均显著高于增殖期（P<0.05）。干扰或过表达PSMB5后,牛骨骼肌卫星细胞EdU阳性细胞率与对照组相比,差异均不显著（P>0.05）。干扰PSMB5的表达后,细胞分化形成的肌管数量明显少于对照组,分化标志因子MyHC的蛋白表达水平显著低于对照组（P<0.05）;而过表达PSMB5后,细胞分化形成的肌管数量明显多于对照组,分化标志因子MyHC的蛋白表达水平显著高于对照组（P<0.05）。【结论】PSMB5蛋白对牛骨骼肌卫星细胞的增殖没有明显影响,但对牛骨骼肌卫星细胞的成肌分化过程具有显著的调控作用。干扰PSMB5表达可以抑制牛骨骼肌卫星细胞的成肌分化进程,而过表达PSMB5可以促进牛骨骼肌卫星细胞体外成肌分化进程。探明PSMB5蛋白对牛骨骼肌卫星细胞增殖和成肌分化的具体调控作用,为进一步开展PSMB5在牛成肌分化中的调控机制研究奠定了基础。     

神蜂精的药效学试验 Ⅱ.神蜂精对虎斑蛙神经传导和肌肉收缩力的影响

神蜂精对虎斑蛙的神经电位传导有很强的阻滞作用． ２５％ 的神蜂精溶液在给药后４ ｍ ｉｎ 对蛙坐骨神经动作电位的传导开始有明显的阻滞作用（Ｐ＜ ０．０５）; ５０％ 以上神蜂精溶液在２ ｍ ｉｎ 内就开始有显著阻滞作用（Ｐ＜ ０．０５）,并随给药时间推移,阻滞作用不断加强,表现出明显的时程效应．此外,不同剂量的神蜂精组间还表现出明显的剂量依赖性阻滞效应（ｒ＝ ０．９８）,而对照组１０ ｍ ｉｎ 内仍无阻滞作用．神蜂精对蛙的肌肉收缩力也有抑制作用．在给药后２～４ ｍ ｉｎ, ２００％ 的神蜂精（指内含２００个蜂单位蜂毒）与对照组对蛙缝匠肌收缩力均有抑制作用,但前者明显高于后者（２ ｍ ｉｎ 时, Ｐ＜ ０．０１; ４ ｍ ｉｎ 时, Ｐ＜ ０．００１）,且１０ ｍ ｉｎ 后肌肉收缩完全受抑制．上述试验表明神蜂精具有较强的阻滞神经动作电位传导和抑制肌肉收缩作用,证明了神蜂精对椎间盘突出症等病症引起的神经酸痛和肌肉犟痉痉挛具有较好的缓解治疗作用．     

我国部分地方鸡种羽性伴性遗传观察

对我国部分地方鸡种泰和鸡、仙居鸡、固始鸡、萧山鸡、油鸡、狼山鸡（Ｎ系）等进行了羽性伴性遗传观察。结果表明,泰和鸡、仙居鸡为快羽型,固始鸡、萧山鸡、油鸡为慢羽型,狼山鸡（Ｎ系）为快慢羽型。这些鸡种按快慢羽伴性遗传配套杂交,Ｆ１代均能自别雌雄。     

鲢鱼肌肉热变性特点的研究

本文报告了鲢鱼肌肉受热时,其Vp值、失水率以及过氧化物酶活力的变化特点。指出在75℃和80℃下加热时,其肌肉过氧化物酶完全失活时对应的Vp值差异较小,分别为51min和55min;而对应的失水率相差较大,为18.2％和24.2％。     

Response of rainbow trout (Oncorhynchus mykiss) to varying dietary astaxanthin/canthaxanthin ratio: colour and carotenoid retention of the muscle

Rainbow trout with an average initial weight of 160 g were fed during 42 days diets containing varied keto‐carotenoids astaxanthin (Ax)/canthaxanthin (Cx) ratio, as follows: Ax 100% : Cx 0%; Ax 75% : Cx 25%; Ax 50% : Cx 50%; Ax 25% : Cx 75% and Ax 0% : Cx 100%. Muscle colour and carotenoid muscle retention were studied. Colour parameter values for mixed astaxanthin–canthaxanthin‐fed fish were intermediate between those obtained for Ax 0% : Cx 100% fed fish group and for Ax 100% : Cx 0% fed fish group. Concerning muscle carotenoid retention, it has been observed that as the level of canthaxanthin in diet increased, the muscle total carotenoid retention decreased. In the mean time, as the level of canthaxanthin in diet increased, the muscle astaxanthin retention decreased while that of canthaxanthin increased. The results reported here provide further evidence of non‐beneficial effects in terms of muscle colour and muscle carotenoid retention of the use of varying dietary astaxanthin/canthaxanthin ratio for feeding rainbow trout compared to values obtained for astaxanthin‐only feed.     

Effect of triploidy on muscle cellularity and flesh quality of turbot (Scophthalmus maximus)

Production of triploid turbot is a relevant goal for the aquaculture industry due to the benefits associated with their sterility and growth. In order for a better understanding of the final quality of the species, muscle cellularity and quality parameters of the flesh were studied in seven diploid and seven triploid turbot after sexual maturation. White muscle cellularity was evaluated throughout white muscle cross‐sectional area from the epaxial left muscle section of each fish. To ascertain the flesh quality, several physico‐chemical parameters (moisture, ash, protein, total fat, fatty acids and minerals) were analysed, and textural mechanical properties (springiness, hardness, chewiness, cohesiveness, gumminess and adhesiveness) were determined objectively with a texturometer. Muscle cellularity was different between both groups, such that muscle fibre density was higher for diploid specimens (P < 0.001) and muscle fibres diameters were higher for triploids (P < 0.001). Both ploidy groups showed no significant differences in moisture, ash, protein and total fat content (P > 0.05). All textural properties analysed showed no significant differences between both ploidy groups (P > 0.05). In both ploidy groups, fibre density and fibre diameter showed no significant correlations (P > 0.05) with textural parameters such as springiness, cohesiveness, chewiness and adhesiveness. Ploidy did not affect fatty acid composition, with the exception of eicosapentaenoic acid (C_20:5ω3) which was higher in the triploid group. No significant differences (P > 0.05) existed between diploid and triploid turbot in content of all minerals analysed. According to our results, the ploidy status determines significant variations on muscle cellularity but does not influence the flesh quality of the turbot.