不同配打模块中各尺寸片烟化学成分的变化

【目的】明确不同配打模块烟叶在打叶后片烟质量的变化规律。【方法】以河南中烟工业有限责任公司4个浓香型多等级配打模块片烟为研究对象,从常规化学成分、糖类物质、多酚类物质、非挥发性有机酸4个方面进行分析,研究不同尺寸片烟化学成分的差异。【结果】①不同配打模块中,不同尺寸片烟的还原糖、总糖、烟碱含量存在一定差异,其中25.40 mm片烟和≤25.40～12.70 mm片烟的常规化学成分相对较为协调。②不同配打模块中,不同尺寸片烟的葡萄糖、果糖含量和糖类物质总量存在一定差异,其中25.40 mm片烟和≤25.40～12.70 mm片烟的糖类物质含量较高,≤2.36 mm片烟的糖类物质含量最低。③不同配打模块中,不同尺寸片烟的绿原酸含量和多酚类物质总量存在一定差异,25.40 mm片烟和≤25.40～12.70 mm片烟的多酚类物质含量较高,≤2.36 mm片烟的多酚类物质含量最低。④不同配打模块中,不同尺寸片烟的草酸、苹果酸、柠檬酸含量和非挥发性有机酸总量存在一定差异,其中25.40 mm片烟和≤25.40～12.70 mm片烟的非挥发性有机酸含量较低,≤2.36 mm片烟的非挥发性有机酸含量最高。⑤由主成分分析可知,不同配打模块中,不同尺寸片烟主要化学成分综合得分的变化规律相同,均表现为25.40 mm片烟得分最高,≤25.40～12.70 mm片烟得分仅次于25.40 mm片烟,≤2.36 mm片烟得分最低。【结论】不同尺寸片烟主要化学成分的变化规律不受地区和部位两个因素的影响,且在不同配打模块烟叶中变化规律表现一致,均以25.40 mm片烟的化学成分最协调,综合得分最高,可将该尺寸片烟作为中高档卷烟产品的原料;≤2.36 mm片烟的内在化学品质较差,化学成分综合得分最低,在生产加工过程中可将该尺寸片烟筛分后用作烟草薄片的原料。     

黑斑侧褶蛙变态前后身体大小的变化 及对植物血凝素的反应模式

为了解不同发育阶段黑斑侧褶蛙（Pelophylax nigromaculatus）身体大小和对植物血凝素（Phytohemagglutinin-P,PHA-P）溶液的反应,在室温为（25±2）℃条件下,戈斯纳37、38～39、40～41、42～43、44～45和46期蝌蚪被取样,测定了体重、体长、尾长、体全长和重长比,以及注射PHA-P溶液前（0 h）和注射后3,6,9和12 h被注射部位皮肤组织的增厚程度的变化。不同发育阶段蝌蚪的体重无显著差异（P>0.05）,体长、尾长和体全长均随发育进程推进而缩短（P<0.05）,但重长比在登陆前后明显增大（P<0.05）。登陆前（37～43期）蝌蚪对PHA-P的反应的峰值出现于注射后3 h（P<0.05）,登陆后（44～45期和46期）出现于注射后6 h（P<0.05）,但不同发育阶段的最大PHA-P反应无明显的组间差异（P>0.05）。黑斑侧褶蛙登陆后尾部萎缩,重长比明显增加,这些特征有利于提高其对陆生环境的适应性,但对PHA-P的反应的峰值被延迟,这可能是造成蝌蚪登陆后存活率低的主要原因之一。     

绵羊SPP1和PLCB3基因多态性与产羔数的关联分析

试验旨在探究SPP1基因g.36651870T>C位点多态性、PLCB3基因g.41871219T>C位点多态性与绵羊产羔数之间的关系,以期寻找绵羊产羔数性状相关的分子标记.利用全基因组重测序结合Sequenom MassARRAY?SNP技术对多羔羊(小尾寒羊、湖羊、策勒黑羊)和单羔羊(滩羊、苏尼特羊、萨福克羊和草原...     

单叶刺槐半同胞子代叶片的滞尘能力及叶表SEM特征分析

以单叶刺槐母本(A1-1)及6个叶形产生明显变异的半同胞子代无性系(A20-5、B24-3、C24-2、B23-1、C24-1、C23-1)新鲜叶片为材料,测定各样本的单位叶面积总颗粒物滞留量、颗粒物粒径分析及叶表微观结构SEM特征,通过相关性分析,筛选与滞尘能力相关的叶形及SEM指标,运用隶属函数法,依据各样本滞尘指...     

Effects of body size and water temperature on food consumption and growth in the sea cucumber Apostichopus japonicus (Selenka) with special reference to aestivation

To investigate the effects of body size and water temperature on feeding and growth in the sea cucumber Apostichopus japonicus (Selenka), the maximum rate of food consumption in terms of energy (C_maxe; J day^?1) and the specific growth rate in terms of energy (SGRe; % day^?1) in animals of three body sizes (mean±SE) – large (134.0±3.5 g), medium (73.6±2.2 g) and small (36.5±1.2 g) – were determined at water temperatures of 10, 15, 20, 25 and 30°C. Maximum rate of food consumption in terms of energy increased and SGRe decreased with increasing body weight at 10, 15 and 20°C. This trend, however, was not apparent at 25 and 30°C, which could be influenced by aestivation. High water temperatures (above 20°C) were disadvantageous to feeding and growth of this animal; SGRe of A. japonicus during aestivation was negative. The optimum temperatures for food consumption and for growth were similar and were between 14 and 15°C, and body size seemed to have a slight effect on the optimal temperature for food consumption or growth. Because aestivation of A. japonicus was temperature dependent, the present paper also documented the threshold temperatures to aestivation as indicated by feeding cessation. Deduced from daily food consumption of individuals, the threshold temperature to aestivation for large and medium animals (73.3–139.3 g) was 24.5?25.5°C, while that for small animals (28.9–40.7 g) was between 25.5 and 30.5°C. These values are higher than previous reports; differences in sign of aestivation, experimental condition and dwelling district of test animals could be the reasons.     

Observations on growth, sexual maturity and spawning performance of pond-reared Penaeus merguiensis

This 12‐month preliminary study investigated the development of sexual characters, primary sexual maturity, ovarian maturity and spawning performance of pond‐reared Penaeus merguiensis in relation to culture conditions in south‐east Queensland, Australia. Post‐larvae of P. merguiensis were produced and cultured in two 60‐m³ tanks during the first 14 weeks. Before winter, they were harvested and stocked in three different overwintering facilities: a 200‐m² covered pond, two 60‐m³ outdoor tanks and a 15‐m³ indoor, recirculated tank at a stocking density of 10 individuals m^?2. The development of sexual characters was found to be similar to that reported previously in wild P. merguiensis. Males matured at younger ages and smaller sizes than females. Overall, the average size at primary sexual maturity of pond‐reared P. merguiensis was 23.1 mm carapace length for males (possessed spermatophores) and 29.3 mm for females (being impregnated). Water temperature and the availability of natural food strongly influenced prawn growth, maturity rate and their subsequent spawning performance. Growth, maturity rate and spawning performance of prawns in the covered pond were significantly higher than in the other overwintering facilities. Prawns started mating at 6–7 months, reached full ovarian maturation and spawned as early as about 8 (peaked at 9–11) months from hatching, producing high fecundity and viable larvae. There was a strong relationship (P < 0.001) between prawn size and fecundity. The results of this study suggest a potential for using pond‐reared broodstock P. merguiensis for hatchery production and for domestication or selective breeding programmes.     

Tailoring codend mesh size to improve the size selectivity of undifferentiated trawl species

Tiger flathead, Neoplatycephalus richardsoni (Castelnau), and sand flathead, Platycephalus bassensis Cuvier, are undifferentiated and managed with a common legal minimum length (LML). The Commonwealth Trawl Sector (CTS) and the Tasmanian Danish‐seine fishery (TDSF) use a minimum codend mesh sizes of 90 and 70 mm, respectively. The codend mesh size should be tailored to the LML, which is based on the length of first maturity of females (M₅₀). This study found the length–girth relationship of N. richardsoni and P. bassensis was not significantly different. Using the covered codend method, these two species had 50% retention lengths (L₅₀) of 294 ± 2 and 307 ± 3 mm, in 70‐mm and 90‐mm codends, respectively. L₅₀ estimates for mesh sizes from this study and others produced a curvilinear relationship: y = 120 ln(x) ? 214, with an r² of 0.8504. The size at maturity (M₅₀) for female N. richardsoni was 337 mm, which is larger than the estimate for female P. bassensis (247 mm). There is a mismatch between the estimates of L_50, the estimates of M₅₀ and the LMLs in each fishery, leading to suboptimal exploitation of female Platycephalus. The model produced in this paper recommends a codend mesh size of 98 mm for both fisheries to exploit Platycephalus species sustainably.     

胶州湾鱼类生物量粒径谱特征

为了解胶州湾海域鱼类群落粒径结构特征,本研究根据2016-2017年4次底拖网调查数据构建了胶州湾鱼类生物量粒径谱,比较分析了各季节鱼类生物量粒径谱特征参数的异质性。结果显示,胶州湾Sheldon型鱼类生物量粒径谱呈现单峰模式,鱼类粒径范围为-3~10粒径级,粒径分布相对均匀,且峰值位于5~6粒径级,主要由大泷六线鱼和褐菖鲉等小型鱼类构成。各季节鱼类标准化生物量粒径谱曲率和曲度差异显著,其中春季曲率最大且曲线较平缓,夏季曲率最小且曲线相对陡峭。谱线曲度和曲率的季节变化主要与粒径小的细纹狮子鱼、大泷六线鱼、玉筋鱼及长丝虾虎鱼等地方常栖性种类和赤鼻棱鳀、白姑鱼等季节洄游性种类的出现有关。Abundance-biomass comparison(ABC)曲线表明,春季处于未干扰状态,冬季处于中度干扰状态,夏秋季处于严重干扰状态。研究表明,胶州湾鱼类群落总体处于严重干扰状态,鱼类生物量谱呈现单峰型,粒径结构以小型粒径鱼类为主,且地方常栖性和季节洄游性鱼类等补充群体的数量和粒径大小影响鱼类生物量粒径谱的峰型和曲率。     

The effect of hepatic passage on postprandial plasma lipid profile of rainbow trout (Oncorhynchus mykiss) after a single meal

For the first time, pre‐ and post‐hepatic plasma lipid profiles were monitored following a single meal in a free‐swimming, non‐anaesthetized fish. Rainbow trout (Oncorhynchus mykiss; 700–1500 g; 10 °C) were equipped with cannulae in the dorsal aorta (DA) and hepatic portal vein (HPV). Simultaneous blood samples, taken from both cannulae at 0, 3, 6, 12, 24 and 48 h postprandial, revealed the time course of the plasma lipid profiles following a single meal (1% of body mass). Primarily monounsaturated fatty acids with the exception of 18:1n ? 9, increased significantly from baseline by 12 h postprandial without greatly affecting total plasma lipid concentrations. Total plasma lipids then showed a small peak at 24 h postprandial, coinciding with a peak in triacylglycerols. We conclude that assimilation of lipids from the digest into the plasma is slower than reported for proteins and carbohydrates in the same species. Furthermore, as there were no significant differences between the HPV and DA, no measurable effect of hepatic passage on plasma lipid levels was resolved. Therefore, we also conclude that, in contrast to that in higher vertebrates, hepatic passage does not seem to have a major role in rainbow trout for modulating the postprandial plasma profile of lipids.     

南太平洋延绳钓长鳍金枪鱼生物学组成及其与栖息环境关系

长鳍金枪鱼(Thunnus alalunga)经济价值高,是我国延绳钓渔业重要的目标鱼种。根据2013年9月~2014年1月和2014年4~8月我国金枪鱼观察员在南太平洋东部海域收集的长鳍金枪鱼样本和海洋环境数据,对其生物学组成和栖息环境进行了研究。结果表明:叉长(FL,cm)与体质量(WW,kg)的关系为:WW=3×10-5×FL2.909 9(雌雄性,R2=0.915 3);体长(TL,cm)与叉长(FL,cm)关系为:TL=1.033 6FL+2.555(R2=0.961 4);叉长(FL,cm)与两背鳍间距(LD1D2,cm)的关系为:LD1D2=0.248 5FL+1.238 1(R2=0.815 1);利用各水层长鳍金枪鱼渔获率(catch per unit effort,CPUE)推测其主要的栖息水层为150~270 m,栖息水层温度范围16~22℃,盐度范围35.0~35.6,其中最高资源丰度主要分布在190~230 m的水层,对应的温度为18~20℃,盐度为35.2~35.4。研究结果可为掌握南太平洋长鳍金枪鱼栖息环境提供基础数据。