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81.
选用24头长白×荣昌杂交仔猪进行2×2因子的代谢试验,试验设2个有效磷水平(0.36%和0.26%)、2个植酸酶添加水平(0、750FTU/kg),共4个处理组,每个处理组设6个重复仔猪起始均重16.9kg,饲粮DE12.8MJ/kg,试验期2周。结果表明:饲粮添加植酸酶,仔猪平均日增重(ADG)、增重/kgW0.75(GPW)、F/G、增重/代谢能(GPM)、蛋白质物质价值(BV)、净蛋白效率比(PER)、钙消化率(CD)、钙沉积率(CR)、磷消化率(PD)和磷沉积率(PR)分别提高10.6%、7.2%、7.9%、7.7%、11.6%、6.7%、4.3%、4.9%、19.6%(P<0.01)、21.3%(P<0.01),每千克增重的饲粮成本(CPG)降低6.6%;植酸酶对仔猪血清理化指标无显著影响,但血清磷浓度趋于升高,血清钙、血清尿素氮浓度趋于降低。降低饲粮有效磷,ADG、GPW、F/G、GPM、BV、PER、PD和PR分别降低3.8%、3.3%、3.2%、4.6%、9.6%、3.2%、7.7%、6.9%,CD、CR和CPG分别增加11.1%、11.6%、3.0%(P>0.05)。  相似文献   
82.
不同生长模型估计籽鹅早期体重发育规律及遗传参数   总被引:8,自引:0,他引:8  
陈清  赵文明  吴信生  陈国宏 《中国家禽》2006,28(24):146-147
运用Logistic,Gompertz,VonBertalanfy和Cubic4种非线性生长模型对籽鹅1~1周龄的平均体重进行拟合,并分析生长发育规律及遗传参数。结果表明:虽然4个模型都能描述籽鹅的生长过程,拟合度均超过额0.99;但Logistic模型更符合实际饲养情况,能更好地预测体重,为最佳模型,其相应的体重极限参数A为2267.63g,调节参数B为16.27,瞬时相对生长率C为0.47,生长的拐点时间为6.48周龄,拐点体重为1136.81g。  相似文献   
83.
灵芝多糖液体发酵条件优化   总被引:3,自引:0,他引:3  
从一系列灵芝(Ganoderma sp.)菌种中筛选出多糖产量高、生长快的紫灵芝菌株(G.japoncium),研究了不同氮源、碳源及金属离子对紫灵芝产多糖的影响。结果表明,以2%的蔗糖为碳源,0.2%的豆饼粉为氮源,0.2%的FeSO4为培养基可获得较高多糖。发酵罐放大实验表明,采用同样的培养基,每100mL发酵液胞外粗多糖含量可高达181.7mg,每100mL发酵液菌丝体含量可高达151.0mg,发酵过程中pH值的变化比较缓和,相对摇瓶生长,发酵生产可获得更多的灵芝多糖。  相似文献   
84.
研究了C源、N源、pH、温度和料水比及不同培养基对勺状亚侧耳(Hohenbuehelia petaloides)Hp.831菌丝生长的影响。试验结果表明,该菌丝生长的最适温度、pH、C源、N源和含水量分别为25~30℃、6~7、羧甲基纤维素钠、蛋白胨和60%~70%;马铃薯和松针的热水提取液可促进该菌菌丝生长;该菌菌丝在配方7培养料上长势最好,菌丝生长动态符合logistic方程:Y=109.6/(1 60.1131e-0.1894x)(y=菌丝生长长度mm,x=培养时间d)。  相似文献   
85.
Deltamethrin (DM) is a pyrethroid insecticide widely used in Brazilian crops and in pest-control programs because of its low environmental persistence and toxicity. It has been shown to exert a wide range of effects on non-targeted organisms including fishes. The aim of this study to evaluate the effects of deltamethrin through the hematological and biochemical parameters using Ancistrus multispinis as animal model. First, blood of A. multispinis was collected by cardiac puncture in order to evaluate the basal values of the total cell counts, hemoglobin and hematocrit rates. A. multispinis showed low number leukocytes, red blood cells and hemoglobin compared to other species. The intoxication with DM (0.1 or 0.3 mg kg−1) induced leukocytosis and increases the number of erythrocytes and hemoglobin levels 96 h after the injection when compared to vehicle-injected animals. The injection of lipopolysaccharide (LPS) also induced a significant leukocytosis and increased the erythrocytes number 4 h after the injection. The combination of the higher dose of DM with LPS showed an additional effect in the number of leukocytes and erythrocytes. The GST and EROD activities were also evaluated in the gills and liver, respectively, 96 h after intoxication with both doses of DM. The GST activity decreased after DM intoxication in both doses while EROD activity was not significantly different. These results suggest that A. multispinis is a valuable model for ecotoxicological studies. Also, DM can affect the metabolizing system (GST) and immunologic system of A. multispinis, a condition that can be worsened in the presence of inflammation or infection.  相似文献   
86.
The present study in which 42 female rats, each weighing 200−250 g, were used covered a period of 21 days. The animals were divided into six groups. The first group served as the control group, whereas Group 2 was administered propolis at a dose of 200 mg/kg/bw in drinking water for 21 days. Group 3 was first provided with normal drinking water for a period of 14 days, and was subsequently administered propolis at a dose of 200 mg/kg/bw in drinking water for 7 days. Group 4 was first given normal drinking water for 14 days, and was secondly administered 100 ppm fluoride as a sodium fluoride in drinking water for 7 days. Group 5 was first administered propolis alone at a dose of 200 mg/kg/bw in drinking water for 14 days, and was secondly administered 100 ppm fluoride in association with 200 mg/kg/bw propolis for 7 days. Finally, Group 6 was first provided with normal drinking water for 14 days, and was secondly administered 100 ppm fluoride in association 200 mg/kg/bw propolis for a period of 7 days. At the end of the 21st day, blood samples were collected from the heart of each animal into both heparinised tubes and tubes without anticoagulants. Glucose, triglyceride, cholesterol, total protein, and uric acid levels, and aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP) activities in the serum, as well as malondialdehyde (MDA) levels, glutathione peroxidase (GSH-Px) in the plasma, erythrocyte superoxide dismutase (SOD) and catalase (CAT) activities were measured. When compared to the control group, statistical differences were determined to exist with respect to oxidative stress parameters which involved increase in MDA levels in Groups 4−6, decrease in SOD activity in Groups 4 and 6, increase in CAT activity in Groups 5 and 6, and decrease in GSH-Px activity in Groups 4 and 6. Furthermore, in comparison to the control group, significant differences were observed with respect to certain serum biochemical parameters, including decrease in glucose levels in Groups 5 and 6, decrease in triglyceride levels in Groups 2 and 4, decrease in cholesterol levels in Groups 2 and 5, decrease in the total protein level of Groups 4−6, decrease in the ALT activity of Groups 5 and 6, increase in the AST activity of Group 4, decrease in the ALP activity of Groups 2−6 and increase in the uric acid level of Group 2. In the groups that were administered propolis in association with fluoride, improvement was observed in some oxidative stress parameters and certain other biochemical parameters. Changes determined in the oxidative stress parameters (especially MDA and SOD) were indicative of the anti-radical activity of propolis on the free radicals generated by sodium fluoride. However, the values not drawing completely close to those of the control group can be explained with propolis not being able to completely eliminate the free radicals and the other adverse effects generated by fluoride.  相似文献   
87.
本文旨在研究微生物发酵豆粕对仔猪生长及血清指标的影响,并且根据肠道组织形态学的微观变化,评价了不同处理的豆粕对早期断奶仔猪肠道形态的影响.选用60头35日龄断奶体重为(8.62±0.21)kg的同窝杜×长×大仔猪,分为试验组和对照组,每组3个重复,每个重复10头,分别饲喂以普通豆粕为对照组,微生物发酵豆粕为试验组的日粮.试验结果表明:饲喂微生物发酵豆粕使仔猪料重比降低8.39%(P<0.05),腹泻指数降低39.96%(P<0.01),血清尿素氮含量降低39.47%(P<0.01),血清IgG含量降低6.35%(P<0.05).豆粕经微生物发酵后减轻饲粮中大豆蛋白对肠道的过敏损伤,使肠道维持良好的结构形态,从而促进营养物质的消化吸收.  相似文献   
88.
通过单因子试验和正交试验,研究了碳源、氮源、温度和酸碱度对白灵侧耳菌丝生长的影响。结果表明,实验范围内玉米粉为最佳碳源,蛋白胨为最适氮源,菌丝生长的最适温度为28℃,最适pH值为6.5~7.5。正交试验表明,白灵侧耳菌丝生长的最佳营养因素组合为:2%玉米粉、0.5%蛋白胨、0.3%磷酸二氢钾和0.1%硫酸镁。  相似文献   
89.
“中苜一号”紫花苜蓿耐盐遗传特性初步研究   总被引:5,自引:1,他引:4  
杨青川  苏加楷 《草地学报》1998,6(3):162-170
以“中苜号”紫花苜蓿耐盐新品种为材料,应用NCⅡ杂交试验方案,研究其耐盐遗传参数,旨在为今后苜蓿耐盐育种提供理论依据。结果表明,在直 迫下,苜蓿的干重、株高和分枝数诸性状的加性产应大于显性效应,狭义跗力较大,分别为0.425、0.387和0.484,具有通过选择进一步提高耐盐性的遗传潜力。  相似文献   
90.
This study was designed to compare the blood physiological and biochemical parameters between plateau Juema minipigs and plain Bama minipigs,and provide a theoretical basis for Juema minipigs served as experimental animals in the future.The blood samples of Juema minipigs were taken in Gannan,and the blood samples of the Bama minipigs were taken in Xi'an,24 blood physiological and biochemical parameters were tested using an automatic analyzer of blood cells and biochemistry.Between the plateau Juema minipigs and Bama minipigs,there were significant differences in PLT,RDW-CV and RDW-SD (P< 0.05) and extremely significant differences in RBC,HGB,HCT,MCH,MCMH,GGT,GLU and CRE (P< 0.01).The plateau Juema minipig had an altitude acclimatization,so it was better than Bama minipig in plateau medical science.  相似文献   
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