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Effects of guanidinoacetic acid supplementation in all‐plant protein diets on growth,antioxidant capacity and muscle energy metabolism of bullfrog Rana (Lithobates) catesbeiana 下载免费PDF全文
Qiu‐Hui Zeng Samad Rahimnejad Ling Wang Kai Song Kangle Lu Chun‐Xiao Zhang 《Aquaculture Research》2018,49(2):748-756
Effects of guanidinoacetic acid (GAA) supplementation in all‐plant protein diets were evaluated on growth, antioxidant capacity and muscle energy metabolism of Rana (Lithobates) catesbeiana. Six diets were prepared: a basal fish meal diet (FM), an all soybean meal diet (SM) and four GAA‐supplemented diets by adding 0.2, 0.4, 0.6 and 0.8 g GAA/kg to the SM diet (GAA2, GAA4, GAA6 and GAA8 diets). Triplicate groups of bullfrog (45 ± 0.2 g) were fed the diets to apparent satiation for 8 weeks. Total substitution of FM with SM led to significantly (p < .05) reduced growth and feed utilization. Adding 0.4 g GAA/kg to the SM diet significantly improved growth performance, and the values were comparable to those of FM group. SM and GAA2 groups showed drastically lower serum total antioxidant capacity than FM, GAA4 and GAA6 groups. Also, SM and GAA2 groups showed significantly lower catalase activity than FM and GAA8 groups. A remarkable increase in serum malondialdehyde concentration was detected in SM and GAA2 groups. FM and GAA6 groups exhibited significantly higher serum creatinine concentration than other groups. Muscle creatine kinase activity and glycogen content were significantly decreased in SM group and application of 0.4–0.6 g GAA/kg significantly improved their values. GAA4 group showed significantly lower pyruvate kinase activity than FM and GAA6 groups. Also, GAA2 and GAA4 groups had significantly lower succinate dehydrogenase (SDH) activity than other treatments. These findings show that supplementing 0.4 g/kg GAA to SM‐based diets improves growth, antioxidant capacity and muscle energy metabolism. 相似文献
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加快现代植保技术体系建设的对策研究 总被引:3,自引:0,他引:3
植保技术体系呈现出病虫害预测预报能力明显提高,防控技术体系日臻完善,农药与药械应用技术稳步发展,植物检疫监管技术基础更加牢固的现状;承载着为领导部门和农民提供病虫灾害防控信息、病虫害科学防控技术指导、农药与药械科学使用监管、依法开展植物疫情管控的重大任务。发展现代植保技术体系,要突出病虫害测报公益性,着力病虫害防控的防灾性,确保农药与药械应用的安全性,关切植物疫情蔓延的毁灭性。建设现代植保技术体系的对策措施是:强化病虫害测报体系与信息网络建设,提升测报技术水平;加强病虫害防控技术支撑与推广能力建设,创新推广模式,大力推进绿色防控;推进农药与药械产品应用技术研发推广和专业化统防统治;加大植物检疫技术研发和执法监管力度。 相似文献
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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
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Nan‐Nan Zeng Ming Jiang Hua Wen Wei Liu Fan Wu Juan Tian Li‐Juan Yu Xing Lu Zhong‐Bao Guo 《Aquaculture Nutrition》2021,27(1):240-251
This study was carried out to evaluate the effects of water temperature (WT) and dietary protein levels on growth, body composition and blood biochemistry of GIFT tilapia (Oreochromis niloticus; initial average body weight: 38.75 ± 0.61g, n = 20). The fish were fed with six diets contained graded levels of protein (209.6, 251.0, 302.4, 354.3, 401.9 and 456.8 g/kg) and raised in each of WT (22°C, 28°C and 34°C) for 8 weeks. Results showed that the growth, feed utilization and protein efficiency were significantly increased with the increase of dietary protein level and followed by the latter platform at each WT. The fish raised at 28 and 34°C showed similar growth performance, and their values were significantly higher than the fish raised at 22°C (p < 0.05). The lipid contents in whole body were decreases with the increase of dietary protein level at each WT. However, the whole‐body protein, ash and moisture contents were not affected by dietary protein level or WT (p > 0.05). The values of serum biochemical indices (ALP, ALT, AST and TCHO) were all decreased with the increase of dietary protein. The optimal dietary protein requirement for GIFT tilapia to achieve maximal growth performance is 374.4, 301.7 and 304.9 g protein/kg diet at 22, 28 and 34°C, respectively. 相似文献
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研制了2CZD-1型段茎式甘蔗种植机,可一次性完成甘蔗种植的开沟、施肥、自动取种、自动排种、覆土和覆膜等工序,适用于宽窄行甘蔗种植。设计了机架、取送种机构、转盘施肥机构、旋耕覆土机构、覆膜机构和液压传动系统等结构,其中取送种机构采用排冗结构实现均匀排种。利用有限元分析软件ANSYS对甘蔗种植机的机架进行模态分析,并通过田间试验获得甘蔗种植机的覆土厚度合格率、种植密度、伤芽率、漏植率及总排肥量稳定性变异系数等性能参数。模拟结果表明,当激励频率为8~80 Hz时,机架容易发生共振,且最大位移可达28.12 mm。田间试验表明,该种植机的种植密度为142325芽/hm^2,覆土厚度合格率为93.6%,伤芽率为2.8%,漏植率为4.7%,种植深度合格率为89.3%,总排肥量稳定性变异系数为5.8%,工作生产率为0.32 hm2/h,符合甘蔗种植机的设计要求,能够显著提高甘蔗种植的效率。 相似文献