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141.
This study was designed to examine the effects of glycinin on growth, digestive ability, immune responses, antioxidant capacity and gene expression levels of golden crucian carp. Golden crucian carp were fed diets containing glycinin at 0, 30, 60, 90 and 120 g/kg, respectively, for 8 weeks. Body weight, weight gain percentage, specific growth rate and feed efficiency ratio were negatively related to the content of glycinin in diet. Activities of protease, acid phosphatase, alkaline phosphatase, lysozyme in hepatopancreas, and activities of catalase, glutathione peroxidase, superoxide dismutase, and total antioxidant capacity in the proximal intestine, mid intestine, distal intestine and hepatopancreas were negatively related to the content of glycinin in diet, whereas malondialdehyde in proximal intestine, mid intestine, distal intestine and hepatopancreas increased directly with the content of glycinin in diet. Furthermore, the relative expressions of TNF‐α and IL‐1β in proximal intestine, mid intestine and distal intestine increased directly with the content of glycinin in diet, whereas the relative expressions of TNF‐α and IL‐1β in hepatopancreas were negatively related to the content of glycinin in diets. The relative expressions of IL‐10 in proximal intestine, mid intestine, distal intestine and hepatopancreas all were negatively related to the content of glycinin in diets. In conclusion, reductions in growth, immunity and antioxidant capacity, intestine inflammation with dysfunction of digestive system occurred in golden crucian carp that fed a diet containing glycinin at 30 g/kg or higher after 8 weeks.  相似文献   
142.
A growth experiment was conducted to investigate the effects of replacement of fish meal (FM) by meat and bone meal (MBM) in diets on the growth and body composition of large yellow croaker (Pseudosciaena crocea). Six isonitrogenous (43% crude protein) and isoenergetic (20 kJ g− 1) diets replacing 0, 15, 30, 45, 60 and 75% FM protein by MBM protein were formulated. Each diet was randomly allocated to triplicate groups of fish in sea floating cages (1.0 × 1.0 × 1.5 m), and each cage was stocked with 180 fish (initial average weight of 1.88 ± 0.02 g). Fish were fed twice daily (05:00 and 17:30) to apparent satiation for 8 weeks. The water temperature ranged from 26.5 to 32.5 °C, salinity from 32 to 36‰, and dissolved oxygen content was approximately 7 mg l− 1 during the experimental period. Survival decreased with increasing dietary MBM and the survival in the fish fed the diet with 75% protein from MBM was significantly lower than other groups (P < 0.05). There were no significant differences in specific growth rate (SGR) among the fish fed the diets with 0 (the control group), 15, 30 and 45% protein from MBM. However, SGR in the fish fed the diets with 60 and 75% protein from MBM were significantly lower than other groups (P < 0.05). No significant differences in feeding rate were observed among dietary treatments. The digestibility experiment showed that the apparent digestibility coefficients (ADC) of dry matter, protein, lipid and energy of MBM were significantly lower compared with those of FM (P < 0.05). Essential amino acid index was found to be correlated positively with SGR in the present study, suggesting that essential amino acid balance was important. Body composition analysis showed that the carcass protein and essential amino acids were not significantly affected by dietary MBM. The lipid and n-3 highly unsaturated fatty acid (n-3 HUFA) in fish muscle, however, significantly decreased with increasing dietary MBM. These results showed that 45% of FM protein could be replaced by MBM protein in diets of large yellow croaker without significantly reducing growth. It was suggested that the reduced growth with higher MBM was due to lower digestibility and imbalance of essential amino acids.  相似文献   
143.
The study assessed the effects of surgically implanted dummy ultrasonic transmitters on physiological response of bighead carp Hypophthalmichthys nobilis in April 2011. Before the surgery, 15 blood samples were extracted randomly from 195 bighead carp samples, and then the rest of the fish were divided into three groups: (1) control group, handing but no tagging, (2) sham group, surgical procedure without implantation of transmitter and (3) surgery group, surgical implantation of transmitters. In 3 h, 24 h, 7 days and 14 days after surgery, 15 fish were extracted randomly from the three groups, respectively, for sampling. Then the plasma samples were analyzed, and physiological measures of stress response (cortisol, glucose), tissue damage [alanine aminotransferase (ALT) and aspartate aminotransferase (AST)] and nutritional status [total protein, globulin, albumin, triglyceride, cholesterol, and alkaline phosphatase (ALP)] were compared. The result showed that there was no significant difference between sham and surgery groups in 3 h, 24 h, 7 days and 14 days after surgery. When compared to the control group, there were significant increases in concentrations of plasma cortisol, glucose, ALT, AST, total protein and globulin of sham and surgery groups in 3 h after surgery. After 24 h, the levels of plasma cortisol, ALT, AST, total protein, globulin and ALP were elevated in both sham and surgery groups, whereas the levels of plasma glucose had declined to normal level and plasma albumin, cholesterol and triglyceride were significantly decreased in both sham and surgery groups. After 7 days, the levels of plasma glucose, albumin and cholesterol continued to decline, while the level of plasma ALT, globulin and ALP had declined but still remained higher for sham and surgery groups than control group; however, the plasma total protein level had returned to normal. After 14 days, there was no significant difference between the three groups. The above results showed that surgical implantation of ultrasonic transmitters had indeed caused significantly negative effects on the physiological response of bighead carp. However, all the negative influences on stress response, tissue damage and nutritional status had disappeared in 14 days after surgery, and the presence of transmitters had no significant negative impact. Therefore, the bighead carp should be temporary cultured at least 14 days for the recovery of physiological response and then released into the free water for the ultrasonic telemetry research.  相似文献   
144.
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   
145.
党的第三代领导集体创造性地运用邓小平的社会发展战略思想,提出了“科教兴国” 和“可持续发展”战略,推动着邓小平提出的“三步走”战略向着既定的目标前进。这是第三代领导集体对社会主义发展战略的新贡献。  相似文献   
146.
皂荚提取物对植物病原菌的抑制作用   总被引:8,自引:0,他引:8  
 豆科植物皂荚是一种传统药用植物,为我国特有种。本文在室内测定了皂荚叶和棘刺乙醇提取物对枯草芽孢杆菌、胡萝卜软腐欧文氏杆菌、番茄疮痂病菌、番茄灰霉病菌、番茄叶霉病菌、棉花枯萎病菌、瓜果腐霉的抑制作用。叶提取物未检测出抗菌活性。棘刺提取物对枯草芽孢杆菌和番茄疮痂病菌都表现出一定的抗菌活性,最低抑菌浓度(MIC)分别为2.5 mg/mL和10 mg/mL。棘刺乙醇提取物在浓度为1 mg/mL时,对4种植物病原真菌的生长都表现出抑制活性,其中对瓜果腐霉生长的抑制率为28.4%。将棘刺乙醇提取物分为石油醚等5个极性不同的萃取部分,其中乙酸乙酯部分对枯草芽孢杆菌、番茄疮痂病菌、欧文氏杆菌都具有明显的抑制作用,且活性强于其它的极性段,对枯草芽孢杆菌和番茄疮痂病菌的MIC分别为1.25 mg/mL和5 mg/mL。乙酸乙酯部分对瓜果腐霉和棉花枯萎病菌的生长也有较强的抑制作用,在1mg/mL时抑制率分别为45.8%和23.9%。研究结果表明,皂英抗菌活性成分主要存在于棘刺中的乙酸乙酯极性段和正丁醇极性段中。  相似文献   
147.
2003年7月中旬开始.某猪场接连发生青年母猪死流产综合症及青年公猪睾丸炎.死流产综合症发生率高达45%以上。经过流行病学调查、乙型脑炎病毒(JEV)血凝抑制试验二次采血检测等.综合诊断为猪乙型脑炎。采用湖北农科院研制的猪乙型脑炎油乳剂灭活疫苗(农业部96新兽药证字第30号)进行免疫接种.之后未再发生青年公猪的睾丸炎,青年母猪(一、二胎)死流产综合症发生率降低至7%以下。现将具体情况介绍如下:  相似文献   
148.
中国土地沙漠化对大气CO_2含量的影响   总被引:4,自引:0,他引:4  
本文根据我国不同地区沙漠化类型的面积、土壤有机碳的含量及沙漠化的正逆转速率,计算了我国沙漠化土地中有机碳的变动。结果表明,我国沙漠化土地0-50cm土层中有机碳的,总贮量为753.143Mt,近40年来因土地沙漠化而释放到大气中的CO2,总量达173.286Mt,而逆转过程中固定的CO2量为59.124Mt碳,所以,近40年来我国沙漠化土地净释放到大气中的CO2量为124.475Mt碳,占全球温带和寒带土地每年释放CO2量133Mt碳的93.5%。  相似文献   
149.
沙坡头地区土壤结皮形成机理的研究   总被引:33,自引:1,他引:33  
本文通过大量的事实和依据论述了结皮形成的物质来源和结皮的形成与土壤性质的关系,表明了粉粒(0.05-0.01mm)含量是结皮形成的关键,并从结皮的发育过程、剖面变化、地理位置和养分含量等方面说明了粉粒的分选和聚积过程,进而论述了粉粒的累积机理、结皮的形成过程及结皮形成-破碎的动态变化。  相似文献   
150.
植物叶面结露时间长短及露量与农作物病虫害,特别是真菌病害的发生有密切的关系。为监测叶露情况我们设计制作了叶露仪。该仪器适合在植物病虫害发生规律的科学研究和大田作物病害预测预报工作中使用。  相似文献   
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