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991.
992.
993.
Yongju Zhao Jiahua Zhang Hong Wei Xinming Sun Biao Mu Mingju Yu Lingbing Wang 《Tropical animal health and production》2010,42(6):1257-1262
Two experiments were undertaken to select the efficient method applied for goat estrous synchronization. In experiment 1,
a total of 120 does (Capra hircus) were divided into five groups with a randomized block design, and the does of treatment 1 were synchronized by intravaginal
sponges impregnated with 30 mg Levonorgestrel inserted for 10 days. Does of treatments 2, 3, and 4 were treated with further
injection of 25 IU follicle-stimulating hormone (FSH), 0.05 mg prostaglandin F2 alpha (PGF2α), and 25 IU FSH + 0.05 mg PGF2α at sponge withdrawal, respectively. The does in the control group (n = 40) without estrous synchronization treatment and natural estrous does were observed. In experiment 2, a total of 140 does
in five goat farms in breeding and non-breeding seasons were treated with the selective efficient procedure. The results presented
that all the employed treatments were capable of inducing and synchronizing estrous goats. According to estrous response and
economy, the use of intravaginal sponges impregnated with 30 mg Levonorgestrel and 0.05 mg PGF2α (treatment 3) is the first choice for estrous synchronization, and 95.0% of synchronized does demonstrated estrus, which
was significantly higher than that of treatment 1 (P < 0.05) and control group (P < 0.01). The percentages of ovulating of treatments 3 and 4 were the same (95.0%), which were significantly higher than that
of treatment 1 (P < 0.01). The ovulation rates among different groups were not significant (P > 0.05). When the selective procedure was applied to five goat farms, 85.7% (120/140) of does demonstrated estrus, and the
kidding percentage, litter size, and prolificacy rate were 53.6%, 0.95, and 177%, respectively. 相似文献
994.
995.
George Rigos Alexandros Samartzis Morgane Henry Eleni Fountoulaki Efthimia Cotou John Sweetman Simon Davies Ioannis Nengas 《Aquaculture International》2010,18(6):1093-1104
The comparative effects of iron-supplemented levels on growth, tissue distribution, haematology and immunology of gilthead
sea bream, Sparus aurata (2 g) were investigated, using four organic (50, 100, 200, 300 mg ORG/kg diet) and one inorganic iron source (200 INOR mg/kg diet).
Fish were treated for 12 weeks with the experimental diets and maintained at a water temperature of 19–22°C. Growth (final
weight and specific growth rate), tissue distribution (spleen, liver and muscle), haematological parameters (red blood cells,
haematocrit, haemoglobin and mean corpuscular haemoglobin concentration) and non-specific immune indexes (respiratory burst
activity and antibacterial activity of serum) were analysed. No significant differences were found in growth and iron tissue
distribution among the tested groups. Red blood cell counting was statistically higher in fish given 50 ORG, 100 ORG, 200
ORG and 200 INOR feeds. However, haematocrit, haemoglobin and mean corpuscular haemoglobin concentration were not significantly
affected by increasing dietary iron. Fish receiving the 100 ORG diet had the best performance with respect to the respiratory
burst activity and significantly higher values for antibacterial activity of serum were obtained in fish fed with the 300
ORG diet. The present findings provided no clear evidence of the optimum iron concentration. However, there was adequate indication
that iron supplementation enhanced the performance of gilthead sea bream, mainly from a haematological and immunological point
of view. 相似文献
996.
997.
通过采用均匀试验设计,在近似于生产的高温贮藏条件(37℃)下,以4%的仔猪预混料为对象,研究不同水平组合的甲酸亚铁、碱式碳酸锌、碱式碳酸铜、硫酸锰对烟酰胺稳定性的影响,并在试验中增设2个对照组(硫酸盐对照组和不添加铁、铜、锰、锌对照组)。贮藏试验期60天。试验结果表明:预混料中添加微量元素导致了烟酰胺的额外损失,随微量元素添加量的增加,烟酰胺的损失率也显著增加(P<0.05)。在贮藏15天和30天烟酰胺损失率分别比硫酸盐组降低了36.16%、11.21%。碱式碳酸盐不同组合对烟酰胺的最大损失率为7.33%。甲酸亚铁、碱式碳酸铜、碱式碳酸锌、硫酸锰与烟酰胺的损失率无显著相关性(P>0.05)。烟酰胺损失率随时间延长显著增加(P<0.05)。烟酰胺的损失率在贮藏前30天占全期损失的74.85%。 相似文献
998.
999.
预警是对中国大豆市场的波动情况进行预报的有效手段。采用中国大豆的需求量增长率作为警情指标,利用1995~2010年的经济数据,选择49个警兆指标。通过时差相关分析法,去除无效指标后,将警兆分为先行、同步和滞后指标,并计算各类指标的权重。利用扩散指数编制先行、同步、滞后指标的预警波动曲线,与大豆需求量增长率曲线比较后发现,先行与同步指标有效,滞后指标稳定性稍差。通过先行指标对2011、2012中国大豆需求量增长率进行验证,证明方法有效性,及为未来的2~3年中国大豆需求量增长率预警奠定理论基础。 相似文献
1000.
Cang Jing Yu Jing Liu Li-jie Yang Yang Cui Hong Hao Zai-bin Li Zhuo-fu 《东北农业大学学报(英文版)》2012,19(1):27-35
The overwintering survival ratio of the cultivar Dongnongdongmai 1 with strong cold-resistance in paramos of Heilongjiang Province in China are over 85%. The tillering nodes are the most important organs for overwintering survival of winter wheat, because there are more substances associated with cold resistance in tillering nodes than those in leaves and roots. Proteins in the tillering nodes of the cold-resistant cultivar Dongnongdongmai 1 grown under field conditions with or without any low-temperature stress were analyzed by 2–dimensional electrophoresis and identified by mass spectrometry. In the range of pH 4–7, the expression of 37 proteins showed obvious difference (±more than two fold) in the proteomic maps of cold-stressed and non-stressed tillering nodes, including a new protein spot. All proteins exhibiting the difference in expression were identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, followed by a database search for protein identification and function prediction. Five groups of proteins were confirmed, namely stress-related proteins (22%), metabolism-associated proteins (35%), and signaling molecules (24%), cell wall-binding proteins (5%), unclear proteins (14%). This indicated that tillering node cells supported the energy requirements of plant growth and stress resistance by signal transduction adapting to metabolism and structure. 相似文献