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101.
A quantification system for huanglongbing pathogen using a competitive polymerase chain reaction method and image-analyzing software were developed to obtain precise results. Significant differences in the quantity of pathogen were thus determined in leaves of two citrus cultivars commonly cultivated in southern Vietnam. Less pathogen-related DNA was detected from the tissue of citrus cultivars that are believed to be more tolerant than susceptible cultivars. The quantification system will be used in studies on pathogen proliferation and movement inside citrus tissue.  相似文献   
102.
The experiment was aimed to investigate the effects of dietary alfalfa powder on the growth performance,body size,slaughter performance,organ index and meat quality of Siji geese.A total of 256 15-day-old geese (half male and half female) with similar body weight were randomly divided into four groups with 4 replicates of 16 geese each.The geese in control group were fed with corn-soybean meal-based diet (control diet),and geese in the experimental groups were fed the basal diet replaced with 10%,20% and 30% alfalfa powder,respectively.The results showed that,compared with the control group,dietary alfalfa powder supplementation had no significant effect on the average daily intake,average daily gain,feed conversion ratio,body oblique length,keel length,shin circumference,semi diving length,chest width and shin length (P>0.05),and also had no effect on the carcass ratio,half-eviscerated carcass ratio and pectoral muscle ratio (P>0.05).However,dietary 20% and 30% alfalfa powder supplementation significantly increased the chest depth (P<0.05),dietary 30% alfalfa powder significantly decreased the full-eviscerated carcass ratio (P<0.05),and dietary 10% alfalfa powder significantly increased the leg muscle ratio (P<0.05) of geese.In addition,dietary alfalfa powder significantly decreased the abdominal fat ratio (P<0.05),raised the growth index of liver,jejunum,ileum,and cecum (P<0.05),and increased the water loss rate of pectoral muscle and leg muscle (P<0.05) compared with the control group.Dietary 10% and 30% alfalfa powder significantly increased duodenal growth index (P<0.05) of geese.In conclusion,dietary alfalfa powder supplementation might improve the slaughter performance (increase chest depth and leg muscle ratio,reduce abdominal fat rate) and organ growth index (increase the growth index of liver,duodenum,jejunum,ileum and cecum).However,dietary alfalfa powder increased water loss rates in pectoral muscle and leg muscle,and 30% alfalfa powder reduced the full-eviscerated carcass ratio of geese.The appropriate supplementation level of alfalfa powder was recommended at 10% in the present study.  相似文献   
103.
研究采用专用微生物发酵制剂生产的生物饲料对奶牛产奶性能的影响。将20头产奶牛随机分成试验组和对照组,以生物发酵料和全价混合精料分别作试验组和对照组奶牛日粮精料,青、粗饲料以及饲养管理条件试验组与对照组相同。结果表明:试验组奶牛头日平均产奶量比对照组多2.61kg,增加11.57%,(p〈0.05),每头增收27.38元。与对照组相比,用生物饲料饲喂奶牛可提高产奶量,经济效益明显。  相似文献   
104.
在实战中使用缉毒犬进行高位搜索是非常必要的,我们现在常见的大中型客货车,车内外高度都超过了1.5米,有的货物在房间内、行李房和货场物品放置高  相似文献   
105.
AA肉鸡腿肌重活体估测方法的探讨   总被引:1,自引:0,他引:1  
以AA肉鸡商品代为试验材料,分析0、7、14、21、28、35、42日龄公、母鸡整体和腿肌的累积生长,建立腿肌重(y)与活重(x)之间的直线回归、幂回归、指数回归、对数回归及多项式回归方程,探讨腿肌重的活体估测方法。结果表明,AA肉鸡的腿肌在后期生长迅速,尤其是公鸡在35~42日龄时期表现突出;腿肌重(y)与活重(x)的幂回归、直线回归、多项式回归方程的拟合精度均在0.95左右,效果较好。  相似文献   
106.
107.
蕨类植物的综合利用价值   总被引:7,自引:0,他引:7  
为更好地开发和利用我国的蕨类植物资源,从蕨类植物的食用、药用、园林绿化和观赏,生产上的指示作用、绿肥、饲料用途及工业用途等多方面作了初步阐述。  相似文献   
108.
AIM:To investigate the changes of expression of P-selectin (Ps) in ischemia-reperfusion myocardium and to observe the effects of heat shock protein (HSP) on the expression of Ps and apoptosis. METHODS:Mature female Wistar rats (n=40) were divided into three groups at random. Under general anesthesia, the rats in heat-shock group were subjected to whole-body hyperthermia, and those in the other two groups were treated with anesthetic alone. Twenty-four hours later, the animals in heat-shock group and in control group were subjected to surgical operative ligation of coronary left anterior descending branch (LAD) for 1 h, then accepted reperfusion for 2 h. Those in sham operation group were also performed surgical operation without LAD ligation for 3 h. After operation, the CK-MB in blood serum, infarct size of left ventricles, HSP70, Bax, Bcl-2, Ps and apoptosis cells were measured. RESULTS:The amount of HSP70 in heat-shock group was significant higher than that in control group and in sham operation group (P<0.05). There was no difference between control group and sham operation group (P>0.05). Compared with control group, the infarct size, CK-MB, apoptosis cells, Bax and Ps in heat-shock group were significantly reduced (P<0.05). However, expression of Bcl-2 was similar (P>0.05). No expression of Ps in sham operation group was detected. CONCLUSIONS:HSP70 may reduce myocardial apoptosis during ischemia-reperfusion. One of the mechanisms is that HSP70 restraines the expression of Bax and Bax/Bcl-2. Ps plays an injurious role in ischemia-reperfusion myocardium. HSP70 is likely to restrain Ps from expression, which may be one of the mechanisms by which heat-shock pretreatment plays a protective role in ischemia- reperfusion myocardium.  相似文献   
109.
以常用熏蒸剂溴甲烷为研究实验对象,采用计算机远程控制技术,通过公用交换电话网(PSTN),利用组态软件和调制解调器(MODEM)将检验检疫机关的监控中心和出口加工厂的熏蒸处理仓库连接,组成仓库熏蒸处理计算机远程监控系统。系统主要由熏蒸专用仓库、监控中心、现场检测、监控软件、MODEM和PSTN等部分组成。实现了远距离、多用途、低成本、高效率的熏蒸处理实时监控。  相似文献   
110.
广西不同甜菜夜蛾种群对杀虫剂的敏感性   总被引:2,自引:0,他引:2  
应用室内浸叶法测定了广西3个甜菜夜蛾种群对杀虫剂的敏感性,结果表明,广西不同菜区甜菜夜蛾种群对杀虫剂的敏感性不同。柳江甜菜夜蛾种群对氟啶脲、溴虫腈和氟虫脲的敏感性最高,分别是南宁种群的3.06、5.90、5.17倍,是桂林种群的2.28、2.56、4.93倍;桂林甜菜夜蛾种群对虫酰肼和多杀菌素的敏感性最高,分别是柳江种群的3.82、10.62倍,是南宁种群的4.91、4.36倍;南宁甜菜夜蛾种群对毒死蜱的敏感性几乎与桂林种群一样,是柳江种群的2.80倍;广西3个甜菜夜蛾种群对氟虫腈、高效氯氰菊酯、阿维菌素和溴氰菊酯的敏感性均相当低,无法求出毒力回归方程。  相似文献   
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