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81.
工厂化养殖仿刺参营养品质分析与评价   总被引:1,自引:0,他引:1  
为了更好地了解工厂化养殖仿刺参的营养成分和品质,本研究采用国标等方法,分别对工厂化养殖、池塘养殖、底播自然生长和海捕野生仿刺参的各项营养成分进行了分析和评价。结果显示,工厂化养殖仿刺参出皮率为62.7%~65.8%,煮后出皮率为24.8%~31.1%,显著高于其他来源仿刺参。工厂化养殖仿刺参的必需氨基酸/非必需氨基酸为0.46~0.50,氨基酸营养价值平均得分为87.89~90.42,均高于其他来源仿刺参,说明其氨基酸营养价值水平较高。在其他营养成分方面,工厂化养殖仿刺参与池塘养殖仿刺参较为相近。自然环境生长仿刺参由于摄食来源广泛、生长周期较长,其蛋白质与脂肪水平普遍高于其他来源仿刺参。综合分析认为,工厂化养殖仿刺参的营养价值与池塘养殖仿刺参相近,在出皮率和氨基酸营养水平上优于池塘养殖和自然环境生长仿刺参,说明工厂化养殖仿刺参具有较好的品质和营养价值。  相似文献   
82.
The effects of cytokinins, carbohydrate sources and cold pretreatment on the conversion of protocorm-like bodies (PLBs) to shoots were investigated for the enhancement of micropropagation of Dendrobium huoshanense C.Z. Tang et S.J. Cheng, an endangered medicinal plant in China. The effects of cytokinins and carbohydrate sources on the conversion of PLBs to shoots depended on their types and concentrations. The best results in terms of shoot development from PLBs occurred on 1/2 MS medium supplemented with 20 μM kinetin and 10 g l−1 maltose. Cold pretreatment at 10 °C for 1–2 weeks significantly enhanced the conversion of PLBs to shoots, and over 1300 shoots were obtained from one gram of PLBs after 3 months of culture. The developed shoots were rooted on growth regulator-free MS medium supplemented with 8 g/l banana paste to give complete plantlets, which were successfully acclimatized with a survival rate of approximately 65%. The results indicate that a suitable cold pretreatment (10 °C for 1 week) followed by the use of 20 μM kinetin and 10 g/l maltose in 1/2 MS medium would produce a large number of shoots from PLBs for plantlet regeneration of D. huoshanense.  相似文献   
83.
送春与多花兰杂种的非共生萌发与快速繁殖   总被引:3,自引:0,他引:3  
用地生兰送春和附生兰多花兰进行种间杂交,对杂交种子进行非共生萌发和快速繁殖研究.结果表明:胚龄7个月、0.1 mol/L KOH处理10 min的种子萌发率最高;种子萌发后原球茎的增殖以Z4 (KC+BA 0.4 mg/L+NAA 0.6 mg/L+KT 0.2 mg/L ) 培养基为最好,增殖系数可达到12.8;在原球茎增殖和分化成苗过程中加入活性碳能够有效地防止切口褐化.  相似文献   
84.
试验结果表明,温度和规格对硬壳蛤同化率的影响不显著(P>0.05);饵料种类对硬壳蛤同化率影响显著(P<0.05).其中小球藻和湛江等鞭金藻的同化率显著高于小新月菱形藻(P<0.05),而小新月菱形藻又显著高于扁藻(P<0.05).  相似文献   
85.
Effects of dietary l ‐carnitine were studied in juvenile black sea bream (Sparus macrocephalus). The semipurified basal diet [crude protein 450 g kg?1 dry matter (DM); crude lipid 126 g kg?1 DM] was formulated to choose white fishmeal as the protein source and fish oil plus corn oil (1 : 1) as the lipid source. Six diets (control + diets 1–5) containing 0.1, 0.12, 0.16, 0.24, 0.39 and 1.1 g of l ‐carnitine kg?1 diet were fed to triplicate groups of black sea bream (initial weight 13.10 ± 0.05 g) for 8 weeks. At the end of the feeding trial, growth performance, body composition and antioxidant status were determined. The results showed that relative growth rate (RGR) was significantly improved by the elevation of dietary l ‐carnitine level from 0.1 to 0.24 g kg?1, but decreased with further increment (P < 0.05). Lipid content decreased significantly (P < 0.05) in the dorsal muscle whereas increased (P < 0.05) in the liver with the addition of dietary l ‐carnitine. Dietary l ‐carnitine supplements elevated enzymatic antioxidants (superoxide dismutase, SOD; catalase, CAT; glutathione‐S‐transferase, GST) activities (P < 0.05) yet decreased the content of non‐enzymatic factor, total sulphydryl groups (TSH) (P < 0.05). In summary, the optimum dietary l ‐carnitine level was 0.284 g kg?1 diet by second‐polynomial regression analysis based on RGR (y = ?647.4x2 +367.97x + 234.55; R2 = 0.977, x = dietary l ‐carnitine levels, y = RGR), and dietary l ‐carnitine addition within the levels adopted in our study could depress lipid peroxidation in tissues of juvenile black sea bream.  相似文献   
86.
A 10‐week feeding experiment was conducted to evaluate the effect of different protein to energy ratios on growth and body composition of juvenile Litopenaeus vannamei (initial average weight of 0.09 ± 0.002 g, mean ± SE). Twelve practical test diets were formulated to contain four protein levels (300, 340, 380 and 420 g kg?1) and three lipid levels (50, 75 and 100 g kg?1). Each diet was randomly fed to triplicate groups of 30 shrimps per tank (260 L). The water temperature was 28.5 ± 2 °C and the salinity was 28 ± 1 g L?1 during the experimental period. The results showed that the growth was significantly (P < 0.05) affected by dietary treatments. Shrimps fed the diets containing 300 g kg?1 protein showed the poorest growth. However, shrimp fed the 75 g kg?1 lipid diets had only slightly higher growth than that fed 50 g kg?1 lipid diets at the same dietary protein level, and even a little decline in growth with the further increase of dietary lipid to 100 g kg?1. Shrimp fed the diet with 420 g kg?1protein and 75 g kg?1 lipid had the highest specific growth rate. However, shrimp fed the diet with 340 g kg?1 protein and 75 g kg?1 lipid showed comparable growth, and had the highest protein efficiency ratio, energy retention and feed efficiency ratio among dietary treatments. Triglycerides and total cholesterol in the serum of shrimp increased with increasing dietary lipid level at the same dietary protein level. Body lipid and energy increased with increasing dietary lipid level irrespective of dietary protein. Results of the present study showed that the diet containing 340 g kg?1 protein and 75 g kg?1 lipid with digestible protein/digestible energy of 21.1 mg kJ?1 is optimum for L. vannamei, and the increase of dietary lipid level has not efficient protein‐sparing effect.  相似文献   
87.
88.
育珠期三角帆蚌的生长及其与珍珠增长的关系   总被引:4,自引:3,他引:1  
通过对三角帆蚌壳长、壳宽、蚌总重(整体湿重)、内脏团湿重、壳重和珍珠重等指标在5-11月间的逐月连续测定,研究了常规养殖模式下育珠期2龄三角帆蚌在主要生长季节的生长规律及其与珍珠生长的相关性。结果表明:珍珠重(PW)与壳长(SL)、壳宽(SW)的关系分别为PW=0.0008SL3.3946 (R2=0.6948)和PW=0.7809SW1.0227 (R2=0.6888);而珍珠重(PW)与蚌重(TW)、内脏团重(BW)和壳重(W)的关系分别为PW=0.0021TW1.5434 (R2=0.7337),PW=0.107BW0.9125 (R2=0.7158)和PW=0.0324W1.1259 (R2=0.7101);三角帆蚌总重(TW)与壳长(SL)、 壳宽(SW)的关系最适合用指数函数进行拟合,其关系式分别为TW=16.003e0.1681SL,(R2=0.7961),和TW=64.311e0.1372SW (R2=0.6822);而内脏团重(BW)和壳重(W)与壳长(SL)、壳宽(SW)的关系则适合为幂函数曲线拟合,关系式分别为BW=0.0188SL3.1427,(R2=0.6927);W=0.0656SL2.7721, (R2=0.8271)和BW=12.446SW0.8974 (R2=0.617);W=19.876SW0.802 (R2=0.7563)。本研究结果发现,珍珠生长与蚌总重、壳长和壳宽等外部测量指标之间的相关性显著,从而无须通过杀蚌取珠而直接通过这些外部生长指标的测定就能较好地了解珍珠的生长,更好地为珍珠养殖生产和管理提供指导。  相似文献   
89.
In order to change for the good flavor in green tea of middle or low grade,roast naked barley (miner ingredient) was added to it.To make tea having functional property,mixed roast naked barley-green tea with one medicinal herb (MH,miner ingredient).This study was performed to investigate the effect of drinking extracts of naked barley-MH-green tea (A group) and adlay-Angelica gigas Nakai-green tea (B group) on the body weights of rats,and volatile flavor components of best effective extract on weight reduction.Forty-eight male Sprague-Dawley rats divided into six groups were fed five different green tea extracts for 8 weeks.The result obtained in the experiment indicated that the change of body weights of rats was affected by A group,B group and others.A group showed highest reduction rate of body weights (36.40%).Reduction rate of body weights on the B group (10.10%) was much lower than A group (36.40%).Aroma compounds were extracted by the SDE method.The concentrated aroma extracts were analyzed and identified by GC and GC-MS.The main aroma components of the green tea blended with naked barley and MH were 12 pyrazines having roasty note,methyl butanals having sweet note,hexanal having briskness greenish note,and nerolidol and3-ionone having floral note.  相似文献   
90.
施氮时期对扬稻6号颖果发育及稻米品质的影响   总被引:8,自引:0,他引:8  
通过盆栽试验研究了相同施氮量下不同施氮时期(分蘖期和孕穗期)对扬稻6号颖果发育及稻米品质的影响。与对照相比,增施氮肥(尿素)特别是孕穗肥能显著提高稻米精米率、整精米率、蛋白质含量,降低垩白粒率和直链淀粉含量;在分蘖期和孕穗期施氮肥能明显影响颖果发育,提高粒重,而后者的效果更为明显;在颖果发育过程中不同时期增施氮肥能显著降低颖果的总淀粉和直链淀粉含量,但对支链淀粉含量影响较小;不同时期增施氮肥特别是孕穗肥对淀粉体和蛋白质体的发育及结构均有显著影响,能显著改变籽粒中不同部位特别是腹部淀粉体和蛋白质的分布、数目和形状。与对照相比,淀粉体和蛋白质体的排列更紧密、相互间空隙较少、数量增加、密度增大,淀粉体形状多数呈晶状体。  相似文献   
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