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91.
3种淡水鱼肌肉脂质的组成及营养评价   总被引:4,自引:0,他引:4  
以拉萨河拉萨裸裂尻鱼(Schizopygopsis younghusbandi)、拉萨裂腹鱼(Schizothorax waltoni)、双须叶须鱼Ptychobarbus dipogon)为材料,研究了其肌肉中脂质的组成和含量。结果显示:10种含量最丰富的脂肪酸分别是饱和脂肪酸16∶0和18∶0;单不饱和和脂肪酸16∶1n-9、18∶1n-9和18∶1n-7;n-3型多不饱和脂肪酸20∶5n-3,22∶5n-3和22∶6n-3和n-6型多不饱和脂肪酸18∶2n-6和20∶4n-6。结果表明拉萨河鱼类的脂肪酸模型跟深海鱼类相似,而且n-3型多不饱和脂肪酸的含量相对较高。  相似文献   
92.
Given the universal presence of antagonism between arginine and lysine, determining the optimal dietary arginine/lysine level is of great importance. In this study, eight diets were formulated to contain different arginine/lysine level, followed by a 9‐week feeding trial with shrimps of 2.10 ± 0.01 cm in length and 0.38 ± 0.02 g in weight to determine the effect of dietary arginine/lysine level on growth performance, body composition and enzyme activity. The results showed that the Diet 6 (arginine/lysine level of 29.4/21.0 g/kg) group had significantly higher weight gain rate, and specific growth rate than the control group and most of the other groups (< .05) did. Similarly, the retention efficiency of arginine and lysine in the Diet 6 group was significantly higher than the control group and most of the other groups (< .05). Moreover, most digestive enzymes had higher activity levels in the Diet 6 group, and evident antagonism between dietary arginine and lysine was detected. In summary, dietary arginine/lysine level of 29.4/21.0 g/kg produced the best growth performance, suggesting that a better growth performance in Macrobrachium rosenbergii culture can be obtained by adjusting the dietary arginine/lysine level.  相似文献   
93.
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   
94.
‘糯米糍’荔枝碳素营养储备动态与坐果的关系   总被引:2,自引:1,他引:1  
 以10~12年生的‘糯米糍’荔枝(Litchi chinensis Sonn. ) 为材料, 研究了高产树(60~65 kg·株- 1 ) 和低产树(5~10 kg·株- 1 ) 不同部位(叶片、各级枝条和主干) 碳素营养储备(淀粉) 的差异及季节动态; 分析了不同果实发育阶段树体碳素营养水平与坐果率的关系。结果表明, 果实成熟时高产树各部位的淀粉含量均低于低产树, 而可溶性糖含量高于低产树。果实采收后, 低产树早于高产树抽发新梢。入冬季前(11月底前) , 低产树和高产树分别抽发了3次和2次秋梢。7~11月秋梢生长发育期间, 高产树和低产树均无显著淀粉积累, 11月中旬以后枝梢生长停滞期间, 各部位, 尤其是4 cm直径以内的枝条大量积累淀粉, 在花穗发育前达到高峰。之后, 随花穗发育、开花及坐果而持续降低。高产树和低产树各部位淀粉高峰并无明显差异, 表明坐果量对树体碳素营养储备的累积并无明显的长期影响。叶片、主枝和主干积累的淀粉含量较低, 总体相对稳定; 而4 cm直径以下的枝梢淀粉含量变化剧烈, 说明这些枝梢是更为活跃的碳素储备库。本研究还表明, 坐果早期(花后3周内) 枝条(2 cm直径) 的淀粉含量与该枝条上最终坐果率呈显著正相关, 而果实发育中期(花后8周) 枝条淀粉含量与坐果率无关, 说明早期果实发 育一定程度依赖树体碳素营养储备, 而中后期果实发育几乎不依赖树体储备。  相似文献   
95.
Two field experiments (Experiment I in 2003–2005 and Experiment II in 2004–2005) with carrot c.v. ‘Kazan F1’ were conducted at Trzciana village (50°06′N, 21°85′E). The experiments were arranged in a split-plot design with four replications. Two sub-blocks were identified in both experiments: I, without foliar nutrition; II, receiving plant foliar nutrition. The plants were sprayed three times alternately with: 2% urea solution, 1% solution of multi-component ‘Supervit R’ fertilizer (produced by Intermag, Poland) and again with 2% urea solution. Combinations with diversified nitrogen fertilization were distinguished within both sub-blocks. Experiment I comprised of: (1) Control, (2) Ca(NO3)2 70, (3) Ca(NO3)2 70 + 70, (4) (NH4)2SO4 70 and (5) (NH4)2SO4 70 + 70. Experiment II included: (1) Control, (2) ENTEC-26 35 + 35, (3) ENTEC-26 70 + 70, (4) ENTEC 26 105 + 105, (5) NH4NO3 35 + 35, (6) NH4NO3 70 + 70, (7) NH4NO3 105 + 105. Where 70 kg N ha−1 was used before sowing, whereas 35 + 35, 70 + 70 and 105 + 105 kg N ha−1 were applied before sowing and as top dressing. Solid nitrogen fertilizer was added to the soil (produced by): Ca(NO3)2, Yara International ASA (Hydro); (NH4)2SO4, Zak?ady Azotowe in Tarnów, Poland; NH4NO3, Zak?ady Azotowe in Pu?awy, Poland; and ENTEC-26, COMPO GmbH & Co. KG, Germany. The research aimed at determining the effect of diversified nitrogen fertilization and foliar nutrition on NO3, NH4+, N-total and dry matter (d.m.) concentrations in carrot, and N uptake by storage roots. In Experiment I, nitrogen fertilization did not affect NO3 concentration, whereas in Experiment II, the applied N treatment increased NO3 concentration in carrot in relation to the control, except for the storage roots of plants fertilized with ENTEC-26 35 + 35. Nitrogen fertilization applied in both experiments caused a significant increase in N-total concentration in carrot and N uptake by storage roots in comparison with the control plants. In both experiments, nitrogen fertilization had a different effect on the concentrations of NH4+ and d.m. in carrot. What is more, foliar nutrition treatments in both experiments had a different effect on the concentrations on NO3, N-total, d.m. in carrot and N uptake by carrot storage roots.  相似文献   
96.
从外观诊断、化学诊断、无损测试技术3个方面,总结了目前马铃薯氮素营养诊断的若干方法.对各种方法的应用原理、发展现状进行了阐述,同时,对其他可用于马铃薯氮素营养诊断,但目前仍未采用的方法进行了简要的说明和论述.  相似文献   
97.
血浆蛋白粉和血球蛋白粉在早期断奶仔猪日粮中的应用   总被引:1,自引:0,他引:1  
综述了血浆蛋白粉和血球蛋白粉的营养特点以及在早期断奶仔猪生产中的应用效果,为这2种动物蛋白饲料的合理利用提供一定的理论基础。  相似文献   
98.
The nutritional quality of biofilm, a microbial community associated to an organic matrix, was evaluated in artificial substrate (polyethylene screen) in net cages during 30 days in the Patos Lagoon estuary, Southern Brazil. During this period, samples of biofilm were collected each 5 days for analysis of chlorophyll a, microorganisms abundance, dry weight, protein and lipid contents. During the study, chlorophyll a varied from 0.38 to 2.75 μg cm?2; dry weight between 7.16 and 17.63 mg cm?2; protein content from 0.43 to 1.76 mg cm?2 and lipid concentration between 1.21 and 4.23 mg cm?2. The variation of lipid in the biofilm was closely related to the abundance of free heterotrophic bacteria (34.25–56.54 × 106 cells cm?2), filamentous cyanobacteria (7.5–15.9 × 106 filaments cm?2), flagellates (6.92–12.89 × 106 cells cm?2) and mainly nematodes (29–1,414 organisms cm?2), while protein content varied similarly to the abundance of unicellular centric diatoms (52.10–179.81 × 103 cells cm?2), and nematodes. This information will allow a better management of food supply to raised aquatic organism with the utilization of natural productivity in the culture systems, with considerable decrease in production costs.  相似文献   
99.
A 30‐day feeding experiment was conducted in blue tanks (70 × 50 × 60 cm, water volume 180 L) to determine the effects of dietary lipid levels on the survival, growth and body composition of large yellow croaker (Pseudosciaena crocea) larvae (12 days after hatchery, with initial average weight 1.93 ± 0.11 mg). Five practical microdiets, containing 83 g kg?1 (Diet 1), 126 g kg?1 (Diet 2), 164 g kg?1 (Diet 3), 204 g kg?1 (Diet 4) and 248 g kg?1 lipid (Diet 5), were formulated. Live feeds (Artemia sinicia nauplii and live copepods) were used as the control diet (Diet 6). Each diet was randomly assigned to triplicate groups of tanks, and each tank was stocked with 3500 larvae. During the experiment, water temperature was maintained at 23(±1) °C, pH 8.0 (±0.2) and salinity 25 (±2) g L?1. The results showed that dietary lipid significantly influenced the survival and growth of large yellow croaker larvae. Survival increased with the increase of dietary lipid from 83 to 164 g kg?1, and then decreased. The survival of larvae fed the diet with 83 g kg?1 lipid (16.1%) was significantly lower than that of larvae fed other diets. However, the survival in larvae fed the diet with 16.4 g kg?1 lipid was the highest compared with other artificial microdiets. Specific growth rate (SGR) significantly increased with increasing dietary lipid level from 83 to 164 g kg?1 (P < 0.05), and then decreased. The SGR in larvae fed the diet with 164 g kg?1 lipid (10.0% per day) was comparable with 204 g kg?1 lipid (9.6% per day), but were significantly higher than other microdiets (P < 0.05). On the basis of survival and SGR, the optimum dietary lipid level was estimated to be 172 and 177 g kg?1 of diet using second‐order polynomial regression analysis respectively.  相似文献   
100.
Two parallel experiments were conducted to evaluate the effect of partial substitution of fish meal by two different animal protein sources, blood meal (B) and haemoglobin meal (H) at 0, 50 and 100 g kg−1 of level inclusion in diets for gilthead sea bream, considering a long feeding period for juveniles (Trial 1) and a short feeding period (Trial 2) for on-growing fish. In Trial 1, 33 g juveniles were fed for 242 days and the fish fed with 5% and 10% of haemoglobin dietary inclusion obtained less growth, although feed efficiency, protein efficiency ratio and muscle composition were similar in all diets. In Trial 2, 179 g initial weight fish were fed for 164 days and growth of fish fed H10 showed the lowest growth, although nutrient efficiency and muscle composition were not affected significantly. The results of these experiments demonstrated that blood meal can substitute fish meal (up to 10%) with no effect on performance, but may lead to sensory differences compared with fish fed diet 0, while the inclusion of 5% blood meal had no effect on growth or sensory characteristics. Fish fed 10% haemoglobin inclusion had the poorest growth values.  相似文献   
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