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141.
针对免耕播种机开沟器工作中容易出现缠草堵塞、草土混杂及干湿土混杂影响播种质量的问题,设计了一种新型梯形组合刀盘,制作了试验装置,并进行了土槽和田间试验。试验表明:梯形组合刀盘在秸秆覆盖量不大于1.2kg/m2时,通过性满足要求;梯形组合刀盘工作时组合刀盘和开沟器先后开出"W"沟和"V"沟,草土分离系数达95%,干湿土分离系数可达91.7%。梯形组合刀盘破茬防堵性能可靠,实现了草土分离及干湿土分离,可为种子萌发及出苗创造良好条件。  相似文献   
142.
To study the effect of weaning stress on dairy buffalo calves,5 healthy calves were chosen and weaned,and the blood samples were collected at 1 day before weaning,and 1,14 and 21 days after weaning to analysis blood physiology and biochemistry indexes and immune function.The results showed that the count of white blood cell,lymphocyte,erythrocyte,monocytes and hematocrit,aspartate aminotransferase activity,blood glucose,cortisol and immunoglobulin G contents of dairy buffalo calves were no significant difference between before and after weaning treatments (P > 0.05).The count of neutrophils at 21 d after weaning were significantly lower than that of 1 d before weaning of dairy buffalo calves (P < 0.05).However,lactate dehydrogenase and alanine aminotransferase activity in weaned treatments were significantly higher than those of animals in the treatment before weaning (P < 0.05).The serum urea nitrogen of dairy buffalo calves at 21 d after weaning was significantly higher than that of 1 d before weaning (P < 0.05) and hemoglobin content at 21 d after weaning was significantly lower than that at 1 day before weaning (P < 0.05).It indicated that the physiological and immunity function of dairy buffalo calves were challenged under weaning stress.  相似文献   
143.
The Small-tail Han ewes with 3 years old, (48.7±2.0)kg body weight, carring the multi-lamb gene, were fed with the same diet, mating after one month.18 pregnant ewes were selected and divided into 3 groups(groups 1(control group), 2 and 3).From 90 days of pregnancy, groups 2 and 3 were supplemented with aerosol OT(800 mg/kg) and paraformaldehyde(300 mg/kg), respectively, and the experiments of digestion and metabolism were carried on from 121 to 130 days of pregnancy to study the effect of aerosol OT and paraformaldehyde supplements on the voluntary intake, digestion and metabolism, lambing of late-pregnant ewes.The results showed that when fed with aerosol OT, the voluntary intake of dry matter was increased by 13.0%(P<0.01);The amount of digestion of DM, OM, CP, cellulose and GE was increased by 12.4%(P<0.05), 14.4%(P<0.01), 23.2%(P<0.01), 15.2%(P>0.05) and 27.4%(P<0.01), respectively;The retention of N, Ca and P was increased by 31.1%(P<0.01), 48.5%(P<0.01) and 31.9%(P<0.01), respectively;The serum triglyceride and free fatty acid content tended to decrease;but the apparent digestibility of the dietary nutrients were not significantly affected(P>0.05);The loss of ewe postpartum weight was reduced by 61.9%(P<0.01), a nest of lamb weight was increased by 4.2%(P>0.05).In the condition of feeding paraformaldehyde, the voluntary intake of dry matter was increased by 12.6%(P<0.01);The amount of digestion of DM, OM, CP, cellulose and GE was increased by 15.4%(P<0.01), 16.2%(P<0.01), 22.4%(P<0.01), 14.2%(P>0.05) and 29.0%(P<0.01), respectively;The retention of N, Ca and P was increased by 33.5%(P<0.01), 48.9%(P<0.01) and 36.3%(P<0.01), respectively;But the apparent digestibility of the dietary nutrients were no significantly affected(P>0.05);The serum β-hydroxybutrate and free fatty acid content tended to decrease;The loss of ewe postpartum weight was reduced by 57.1%(P<0.01), a nest of lamb weight was increased by 11.1%(P<0.05).This study showed that by feeding aerosol OT or paraformaldehyde, the intake, digestibility of Ca, P and N could be improved in late-pregnant ewe, the body weight loss, body fat mobilization could be reduced, and the birth weight of litter could be increased.  相似文献   
144.
To investigate the epidemic situation of H6N6 subtype avian influenza virus (AIV) in Guizhou province,A/duck/Guizhou/013/2014 was isolated from Sansui duck in live poultry market of Guizhou in 2014,the hemagglutinin (HA) and neuraminidase (NA) genes of DK/GZ/14 were subjected to clone and sequence analysis.The results showed that HA gene had the highest nucleotide homologies (97.5%) with the duck-origin H6N6 subtype AIV isolated from Eastern China in 2009,and the strains of HA gene proteolytic cleavage sites was P-Q-I-E-T-R-G,which accordeol with the molecular characteristic of low pathogenic AIV (LPAIV).However,NA gene of A/duck/Guizhou/013/2014 had the highest nucleotide homologies (98.2%) with the duck-origin H6N6 subtype AIV isolated from Fujian in 2007.The phylogenetic tree showed that A/duck/Guizhou/013/2014 and Hunan strains located in the same branch,while three duck-origin H6N6 subtype AIV isolated from Guizhou in 2007 and A/duck/Guizhou/013/2014 located in the different branch for HA and NA genes in genetic evolution,which suggested that A/duck/Guizhou/013/2014 was far with the local H6N6 subtype.The results also clearly indicated that duck-origin H6N6 subtype AIV had genetic diversity in duck population in Guizhou.  相似文献   
145.
Limited information is available regarding horse-associated antimicrobial resistant (AR) Escherichia (E.) coli. This study was designed to evaluate the frequency and characterize the pattern of AR E. coli from healthy horse-associated samples. A total of 143 E. coli (4.6%) were isolated from 3,078 samples collected from three national racetracks and 14 private horse-riding courses in Korea. Thirty of the E. coli isolates (21%) showed antimicrobial resistance to at least one antimicrobial agent, and four of the AR E. coli (13.3%) were defined as multi-drug resistance. Most of the AR E. coli harbored AR genes corresponding to their antimicrobial resistance phenotypes. Four of the AR E. coli carried class 1 integrase gene (intI1), a gene associated with multi-drug resistance. Pulsed-field gel electrophoretic analysis showed no genetic relatedness among AR E. coli isolated from different facilities; however, cross-transmissions between horses or horses and environments were detected in two facilities. Although cross-transmission of AR E. coli in horses and their environments was generally low, our study suggests a risk of transmission of AR bacteria between horses and humans. Further studies are needed to evaluate the risk of possible transmission of horse-associated AR bacteria to human communities through horse riders and horse-care workers.  相似文献   
146.
桑枝屑香菇与杂木屑香菇的品质比较   总被引:3,自引:0,他引:3  
以桑枝屑和杂木屑为试材,采用标准及实验室常用方法对香菇营养成分进行测定,研究桑枝屑和杂木屑2种培养料对香菇产量和营养成分(蛋白质、氨基酸、脂肪、多糖、纤维、部分矿质元素)含量的影响。结果表明:桑枝屑栽培的单袋香菇产量比杂木屑的低6.4%,但生物转化率比木屑的高1.7%,粗蛋白质含量是杂木屑栽培的1.03倍,但总氨基酸含量和必需氨基酸含量都比杂木屑香菇中的略低一些;脂肪含量是杂木屑栽培的1.82倍,纤维含量是杂木屑栽培的1.01倍,多糖含量是杂木屑栽培的1.34倍;重金属铅含量仅为杂木屑的11.3%,均达到国家绿色食品标准;矿质元素除钾元素外,钙、镁、铁、锌均高于杂木屑栽培的香菇。可见,用桑枝屑栽培的香菇子实体的营养性和药用保健性优于杂木屑栽培的香菇。  相似文献   
147.
我国黑果枸杞研究进展   总被引:4,自引:0,他引:4  
黑果枸杞集药用价值、经济价值、生态价值于一体,开发应用潜力巨大。现从资源分布、栽培育种、化学成分、遗传学及产品加工等方面,对近年来我国黑果枸杞研究进行了综述,以期为黑果枸杞的进一步开发和利用提供参考依据。  相似文献   
148.
为解决新疆吐鲁番地区甜瓜工厂化育苗当中遇到的容易出现徒长苗,不易培育出适龄壮苗等问题,选用甜瓜品种"西州密十七号"为试材,研究不同浓度植物生长延缓剂多效唑(PP333)和比久(B9)浸种处理对甜瓜幼苗质量的影响。结果表明:甜瓜幼苗发芽势随着PP333溶液浓度的增大而降低,幼苗的株高和下胚轴长显著小于对照;浓度为60mg/L的PP333溶液浸种处理下的幼苗叶片厚度和幼苗壮苗指数最大;60mg/L和80mg/L的PP333溶液浸种处理下幼苗根冠比最大。PP333溶液浸种处理对甜瓜幼苗的株高、下胚轴长、叶片大小和厚度的抑制作用大于B9溶液,可以用于防止幼苗徒长,培育壮苗。  相似文献   
149.
以驻马店市农业科学院园艺所近年来培育的7个辣椒组合(品种)为试材,利用遮阳网模拟弱光胁迫,调查了在弱光胁迫下辣椒植物学性状及产量性状,以株高、茎粗作为参考指标,以叶面积、比叶干质量作为重要指标,以产量、叶绿素a/b值作为主要指标,对其弱光耐受性进行了综合评价。结果表明:弱光逆境胁迫导致辣椒植株增高、茎秆变细、叶面积增大、比叶干质量降低、产量及叶绿素a/b值均降低;且叶绿素a/b值与产量的变化幅度基本一致,该方法可用来鉴定辣椒不同组合的耐弱光性能。  相似文献   
150.
基于"3S"技术的甘肃子午岭自然保护区土地利用变化研究   总被引:1,自引:0,他引:1  
以甘肃省子午岭自然保护区为研究对象,运用"3S"技术,对研究区的地形图、不同时相的TM遥感影像进行数据预处理,并分类提取了研究区2个时段的土地利用信息.对分类信息进行统计分析后并与实地调查数据进行比较,结果表明,近20年来甘肃子午岭自然保护区的森林覆盖面积在稳步提高,乔木林面积明显增加.为甘肃子午岭自然保护区工程的建设提供了基础信息,为林区植物种群生长及分布调查研究提供了宏观数据,并且输出了研究区不同时相土地利用专题图.  相似文献   
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