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61.
通过在Google Earth中采集公共点的WGS84经纬度坐标、在DRG上采集北京54和西安80平面坐标,本文采用布尔莎七参数模型,估算出当阳市WGS84转北京54、西安80坐标和北京54转西安80坐标的转换参数,并用公共点坐标和影像叠合两种方法进行了转换精度检验,结果表明:WGS84转北京54、西安80坐标的误差〈2.5m,北京54转西安80坐标的误差〈0.3m,能满足林业调查规划的精度要求,所求参数可以在林业调查规划中使用。 相似文献
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63.
烟酸对未去势湘中公牛生长性能、肉品质和血清生化指标的影响 总被引:1,自引:0,他引:1
本研究旨在研究烟酸对未去势湘中公牛生长性能、肉品质和血清生化指标的影响。选择1.5岁左右体重[(385.08±15.20)kg]匀称的未去势湘中黑公牛21头,随机分成3组,每组7头,各组分别在基础饲粮中添加0、800、1 200 mg/kg烟酸。预试期14 d,正试期120 d。结果表明:烟酸对公牛的平均日增重、日均采食量、饲料转化率、背膘厚、眼肌面积均没有显著影响(P0.05)。烟酸对背最长肌的p H、肉色亮度和红度值、剪切力、滴水损失以及水分、粗脂肪和粗蛋白质含量均没有显著影响(P0.05)。1 200 mg/kg烟酸显著降低血清总胆固醇和高密度脂蛋白胆固醇(HDL-C)含量(P0.05),800 mg/kg烟酸显著降低血清HDL-C含量(P0.05),烟酸对低密度脂蛋白胆固醇含量没有显著影响(P0.05)。1 200 mg/kg烟酸可以提高血清非酯化脂肪酸(P0.05)和葡萄糖含量(P=0.06),降低血清尿素氮含量(P=0.07)。综上,本研究并没有观察到烟酸对未去势湘中公牛生长性能和肉品质等指标有影响,但对血脂指标有一定调节作用,推测可能是未去势公牛的雄性激素的作用覆盖了烟酸的作用。 相似文献
64.
White spot syndrome virus (WSSV), a rod-shaped double-stranded DNA virus, is an infectious agent causing fatal disease in shrimp farming around the globe. Within shrimp populations WSSV is transmitted very fast, however, the modes and dynamics of transmission of this virus are not well understood. In the current study the dynamics of disease transmission of WSSV were investigated in small, closed populations of Penaeus monodon and Penaeus vannamei. Pair cohabitation experiments using PCR as a readout for virus infection were used to estimate transmission parameters for WSSV in these two species. The mortality rate of contact-infected shrimp in P. monodon was higher than the rate in P. vannamei. The transmission rate parameters for WSSV were not different between the two species. The relative contribution of direct and indirect transmission rates of WSSV differed between the two species. For P. vannamei the direct contact transmission rate of WSSV was significantly lower than the indirect environmental transmission rate, but for P. monodon, the opposite was found. The reproduction ratio R0 for WSSV for these two species of shrimp was estimated to be above one: 2.07 (95%CI 1.53, 2.79) for P. monodon and 1.51 (95%CI 1.12, 2.03) for P. vannamei. The difference in R0 between the two species is due to a lower host mortality and hence a longer infectious period of WSSV in P. monodon. 相似文献
65.
《Journal of Equine Veterinary Science》2014,34(11-12):1324-1328
The experiment was performed to evaluate the ameliorative effect of ascorbic acid (AA) on some hematological parameters and erythrocyte osmotic fragility (EOF) in horses transported by road. A total of 14 horses, consisting of seven experimental and seven control horses, were used for the experiment. Before the transportation, blood samples were obtained by jugular venipuncture from all the horses. Experimental horses were administered with AA (200 mg/kg dissolved in 20 mL of distilled water per os), whereas the control horses were given 20 mL of distilled water per os. Thereafter, the animals were transported for 6 hours and blood samples collected after transportation. Packed cell volume and hemoglobin concentration were higher (P < .05) in experimental than the control group, whereas total leukocytes reduced significantly (P < .05) in experimental in comparison with the control horses. Lymphocyte, neutrophil counts, neutrophil/lymphocyte ratio, and total protein decreased in experimental horses in comparison with control, but they were not significant (P > .05). Erythrocyte osmotic fragility was lower in experimental than the control at 0.3% NaCl concentration (P < .05). The result of the present study revealed that AA ameliorated changes in hematological parameters and EOF induced by road transport stress, partly because of its antioxidant properties. 相似文献
66.
加减四君子汤对仔猪免疫机能及生产性能的影响 总被引:1,自引:0,他引:1
将72头(16.56±0.37)kg长大二元猪随机分为对照组、加减四君子汤组、抗生素组,每组4个重复,每个重复6头(公母各半)。对照组饲喂基础日粮,试验1组在基础日粮中添加中草药加减四君子汤,试验2组基础日粮中添加抗生素和高铜,于试验的第14天和第30天分别称重和采血,测定仔猪的生长性能、免疫指标和生理生化指标。结果显示,在试验第一阶段,中草药加减四君子汤组的平均日增重显著低于抗生素组(P〈0.05),日粮粗蛋白质消化率极显著低于抗生素组(P〈0.01),料肉比显著高于抗生素组(P〈0.05),中草药加减四君子汤组的平均日增重、日粮粗蛋白质的消化率、料肉比与对照组相比差异不显著(P〉0.05);而在试验第二阶段,中草药加减四君子汤组日增重和料肉比与抗生素组差异不显著(P〉0.05),显著优于对照组(P〉0.05);中草药加减四君子汤组粗蛋白质消化率显著低于抗生素组(P〈0.05),与对照组相比差异不显著(P〉0.05);中草药加减四君子汤组淋巴细胞ANAE阳性率在试验的两个阶段均显著高于抗生素组和对照组(P〈0.05),对照组和抗生素组差异不显著;淋巴细胞转化率LTT(PHA)在第一阶段3个处理组之间差异不显著(P〉0.05),在第二阶段中草药加减四君子汤极显著高于抗生素组和对照组(P〈0.01),而对照组和抗生素组之间差异不显著(P〉0.05);血清生化指标各处理组在整个试验期间差异均不显著(P〉0.05)。该结果表明,加减四君子汤具有明显的促生长作用,可提高断奶仔猪免疫力,增强机体抗病力,在猪饲料中添加一定剂量的加减四君子汤对动物健康无不良影响。 相似文献
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68.
为探究取食不同猎物对异色瓢虫实验种群动态的影响,本文利用生命表技术研究了桃蚜、豆蚜和豌豆修尾蚜对异色瓢虫生长发育和繁殖的影响。结果表明,异色瓢虫取食豌豆修尾蚜的整个成虫前期历时最长,为20.20d,雌虫寿命最短,为51.70d,单雌产卵量最低,为704.00粒;而取食豆蚜的成虫前期历时最短,为17.89d,雌虫寿命最长,为69.87d,单雌产卵量最高,为1 175.48粒;取食桃蚜的异色瓢虫各生物学参数与取食豆蚜的结果相类似。根据取食不同猎物异色瓢虫各发育阶段的存活率和成虫的繁殖力,组建了生殖力生命表,发现取食豌豆修尾蚜的内禀增长率(rm)、净增殖率(R0)和周限增长率(λ)最低,分别为0.006、300.312和1.123;取食豆蚜和桃蚜的rm、R0和λ均高于取食豌豆修尾蚜的结果。综合试验结果和实际饲养情况,豆蚜可作为饲养异色瓢虫更适宜的食物。 相似文献
69.
Effect of yeast with bacteriocin from rumen bacteria on laying performance,blood biochemistry,faecal microbiota and egg quality of laying hens 下载免费PDF全文
H. T. Wang W. Y. Shih S. W. Chen S. Y. Wang 《Journal of animal physiology and animal nutrition》2015,99(6):1105-1115
The purpose of this study was to evaluate the effect of yeast with bacteriocin from Ruminococcus albus 7 (albusin B) on physiological state and production performance of laying hens. One hundred and twenty 26‐week‐old Single Comb White Leghorn (Hyline) laying hens were assigned into five groups including: (i) control group, (ii) yeast control (YC), (iii) 0.125% yeast with bacteriocin (0.125B), (iv) 0.25% yeast with bacteriocin (0.25B) and (v) 0.5% yeast with bacteriocin (0.5B). All supplements were added to the experimental diets of the hens from 26 to 46 weeks of age. Samples were collected every 4 weeks. Blood samples were collected from the wing vein for blood biochemical parameters assay, and faecal samples were collected by swab for the microbiota test. The egg production performance was recorded daily, and fresh eggs were collected for quality test. The blood biochemical assay results indicated that the addition of yeast with bacteriocin decreased the AST (aspartate aminotransferase) activity and it also affects the lactate concentration in laying hen blood. The result of egg quality indicated that yeast with bacteriocin supplementation had no effect on the mass of yolk and the strength of eggshell, but it had positive effect on the laying performance under hot environment. Low concentration bacteriocin (0.125B) supplementation could decrease total yolk cholesterol. The faecal microbiota result indicated that the supplementation of bacteriocin increased the lactobacilli counts. The yeast with bacteriocin supplementation significantly decreased the clostridia counts under hot environment condition, especially in hens receiving 0.25B. Combining the data from clinic chemistry, faecal microbiota, egg production and egg quality, the 0.25B supplementation may result in the best physiological parameter and egg production performance of laying hen. 相似文献
70.