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81.
This study compared the sensitivity of acetate tape impression and skin squeezing with that of deep skin scraping for the diagnosis of demodicosis in dogs. Demodex canis was detected in 100% of acetate tape impressions obtained after skin squeezing and in 90% of deep skin scrapings. There was a significant difference (P < 0.001) between the techniques in the total number of mites detected. Acetate tape impression with skin squeezing was found to be more sensitive than deep skin scraping and is an alternative diagnostic method for canine demodicosis.  相似文献   
82.
秸秆还田是培肥地力、改良土壤的重要措施。内蒙古高原向松辽平原过渡地带春玉米区,玉米长期连作导致了耕层变薄、土壤次生盐渍化等土壤退化问题。采用田间定位试验的方法,研究连续多年(8、5、2年)秸秆旋耕还田条件下对土壤微生物的影响。结果表明,秸秆还田土壤中最丰富的细菌类型为变形菌门(Proteobac-teria),其次为放线菌门(Actinobacteria)、芽单胞菌门(Gemmatimonadetes)、拟杆菌门(Bacteroidetes);真菌类型为子囊菌门(Ascomycota)和担子菌门(Basidiomycota)。随着秸秆还田年限的增加,变形菌门和酸杆菌门(Acidobacteria)相对丰度增加、放线菌门相对丰度下降,拟杆菌门相对丰度较稳定;子囊菌门、担子菌门、接合菌门(Zygomycota)相对丰度先下降后上升,而球囊菌门(Glomeromycota)和壶菌门(Chytridiomycota)相对丰度变化规律相反;属水平上Sphingomonas、Lysobacter、Hannaella相对丰度先上升后下降,而Leptosphaeria和Mono-dictys相对丰度变化规律相反;Pseudarthrobacter、Fusarium相对丰度下降,Gaiella相对丰度较稳定;Guehomyces相对丰度增加;并且细菌和真菌相对丰度拐点均出现在秸秆还田5年后。随着秸秆还田年限的增加,土壤细菌和真菌多样性均有所降低;秸秆还田与秸秆不还田土壤的差异物种有Aquicella、Fusicolla和Spizellomyces;由此可推测,秸秆还田增加土壤氮和钾含量,减少病害;试验区连续多年的玉米秸秆还田改变了土壤微生物群落组成,玉米秸秆连续还田5年后土壤微生物多样性有下降趋势。  相似文献   
83.
Protein fractions of cerebral spinal fluid samples were analyzed in an effort to find a reliable, minimally invasive and cost effective method of diagnosing cervical vertebral myelopathy. There were six separate protein fractions analyzed by electrophoresis. In this study we specifically looked for a post beta spike in horses with spinal cord compression. There was no correlation in our study between horses with a post beta spike and CVM as diagnosed by a myelogram.  相似文献   
84.
85.
额济纳胡杨林土壤含水量时空变化的研究   总被引:10,自引:0,他引:10  
使用管状土壤水分仪,对额济纳胡杨林、沙枣林、柽柳林以及其它不同样地的土壤含水量时空变化进行了调查研究。结果表明,大部分样地有大约20CM的干沙层,使表层土壤含水量最低;土壤剖面的30~150CM土层内,随土壤深度的增加,土壤含水量逐渐增大;沙枣林和柽柳林的土壤含水量明显高于胡杨林土壤含水量;土壤质地的变化和三种林型耗水量的差异是土壤含水量高低变化的原因;2004年5月份的土壤含水量明显高于2003年7月份的土壤含水量。  相似文献   
86.
米易县核桃产业发展的思考   总被引:1,自引:0,他引:1  
在论述了米易县核桃产业发展现状的基础上,分析了米易县发展核桃产业的必要性和存在的问题,针时存在问题提出了相应的对策和建议:一是以核桃基地建设为重点,合理规划核桃种植;二是以科技为依托,强化技术支撑体系;三是引进龙头企业,带动核桃产、工、销一体化发展;四是拓宽核桃产业发展的融资渠道;五是建立苗圃基地,确保良种供应;六是制定一系列的优惠政策,促进核桃产业健康快速发展。  相似文献   
87.
Abstract— A12-wk feeding experiment was conducted to study the feasibility of utilizing cluster bean seed meal (CBM) as a replacement for fishmeal in the diets for common carp Cyprnus carpio fingerlings. The replacement levels of cluster bean meal protein in the diets were 25, 50, 75, and 100% of the total fishmeal protein. All diets were isonitrogenous at 33.1% crude protein and isocaloric at 4.8 Kcal/g. There were significant differences in the final individual weights, weight gains, specific growth rates (SGR %/d), feed conversion ratios (FCR), feed efficiency ratio (FER), protein efficiency ratios (PER), and feed intake among fish group ( P × 0.05). Common carp fed the diet containing 50% (CBM) exhibited comparable growth to those fed a fishmeal-based diet. Digestibility of protein, energy and lipid decreased with increasing levels of CBM above 50% of total fishmeal replacement in the diet. Incorporation of CBM in diets significantly affected the dry matter, protein, and energy of whole fish body. These results suggest that CBM can replace 50% of the fishmeal in diet for common carp.  相似文献   
88.
OBJECTIVE: To determine the survival time of Mycobacterium avium subsp paratuberculosis in amitraz-based cattle dip fluid derived from an active dip site in northern New South Wales. PROCEDURE: Following inoculation of triplicate 5 L containers with faeces (0.5 g/L) from a clinical case of bovine paratuberculosis, samples collected up to 8 weeks after inoculation were examined by conventional and radiometric culture. M a paratuberculosis colonies were enumerated on solid media. RESULTS AND CONCLUSIONS: M a paratuberculosis survived in amitraz cattle dip fluid for up to 2 weeks, but not 3 weeks. Where 1% of solids in dip fluid is derived from a clinical case of paratuberculosis, dip fluid may contain viable M a paratuberculosis for at least 2 weeks. These findings have implications for the management of cattle dip sites.  相似文献   
89.
The purpose of this experiment was to study the effects of Gymnadenia conopsea polysaccharide (GCP) extract on growth performance, meat quality and antioxidant function house-fed mutton sheep under oxidative stress, so as to provide experimental basis for extensive research and development of Gymnadenia conopsea and its extracts. Twenty 6-month-old healthy male Small-Tailed Han sheep with body weight of (35.0 ±4.0) kg were randomly divided into two groups. The experimental group (n=10) and control group(n=10). The whole experiment lasted for 42 d and was divided into 3 periods: the first 15 days were the blank period; the middle 15 days were the treatment period; the last 12 days were the observation period ofter modeling. From the first day of the treatment period, the control group was fed with basal diet, and the experimental group was fed pellet basal diet containing 30 mg·kg-1 GCP extract. On the 15th day of the treatment period, the sheep in each group were intraperitoneally injected with 10 mg·kg-1 Diquat solution according to sheep body weight(BW), and then fed for another 12 days. On the 1 st, 15th, 30th, 33rd, 36th, 39th and 42nd morning of the whole experimental period, fasting weight and blood samples were collected before feeding. The serum was separated and the antioxidant indexes (SOD, GSH-Px, T-AOC, MDA) in serum were determined. On the 42nd day of the whole experimental period, 5 sheep randomly selected from each group were slaughtered and meat samples were collected to determine the meat quality. The results showed that the addition of GCP extract to the diet of the sheep could increase the average daily feed intake (P<0.05). When the body was subjected to oxidative stress, the indexes of daily gain and antioxidant enzymes recovered rapidly on experimental group, the mutton drip loss decreased significantly, and the mutton sheer force increased significantly(P<0.05). The results indicated that GCP extract could improve the growth performance of mutton sheep, and alleviated the decline of growth performance and antioxidant performance caused by oxidative stress, and had a certain effect of antioxidant stress.  相似文献   
90.
对黄土沟壑区旱地条件下"龙王帽"、"白玉扁"的不同花型数量分布及遗传力进行了分析,结果表明:"龙王帽"的有效花比例高达91.8,具有较大的丰产潜力,宜作为旱地主栽品种;"白玉扁"有效花比例仅为41.2,雌蕊败育率较高,丰产潜力小,仅宜作为授粉品种;花型主要受遗传因素控制(遗传力高达0.99),环境影响较小.  相似文献   
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