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211.
The purpose of this experiment was to study the immunization rule of the egg yolk antibody affected by different vaccines,immunization dose and injection ways and further to discuss the optimal immunization procedures of the laying hens for the preparation of egg yolk antibody against swine Japanese encephalitis virus.180 brown laying hens without any vaccines were selected and divided into 18 groups randomly,each group of 10 hens.Groups 1,2 were the control groups,injected with the sterile saline;Groups 3 to 10 were injected with subcutaneous or intramuscular injection,and the vaccine was injected with 0.2,0.5,1.0 and 1.5 mL successively.Groups 11 to 18 were also adopted two kinds of injection,followed by the same dose of vaccine immunization.Six eggs of each experimental group were gathered before immune day and after 3,7,10,14,18,21 and 28 days,the egg yolk antibody was extracted and the titer was determined.As a result,the egg yolk antibody titers of groups 1 to 6,11 and 12 were all 0,and no significant immune response produced;The hens from 7 to 10 groups were injected with the inactivated vaccine.After 7 days,the average antibody titer reached the peak,and the duration of the antibody was 14 days.The hens from 13 to 18 groups were injected with the attenuated virus vaccine.After 14 days,the average antibody titer reached the highest value,and the duration of the antibody was 21 days.The egg yolk antibody titers were not significantly different in the two compared experiment groups with the same injection dose but with different injection ways (P>0.05).With the same injection way of each experiment group,and the difference was significant (P>0.05).Compared with some groups with the same injection and vaccine,the titer of yolk antibody was gradually increased with the increase of the immune dose,and the difference was significant (P<0.05).The results showed that,no matter intramuscular or subcutaneous injection,in order to produce a significant immune response to hens,the immune antigen dose was 1.0 mL inactivated vaccine or 0.5 mL attenuated vaccine at least.Compared with the attenuated and inactivated vaccine,inactivated vaccine stimulated the body to produce the antibody faster,but the maintenance time was shorter;The lower dose of attenuated vaccine could stimulate the body to produce antibodies,but the speed was slower,the maintenance time was longer. 相似文献
212.
SHI Li-guang ZHOU Xiong XUN Wen-juan HOU Guan-yu ZHOU Han-lin HUANG Xian-zhou 《中国畜牧兽医》2016,43(1):101-107
This experiment was conducted to study the effect of selenium and vitamin E supplement on semen quality, antioxidant enzyme activities and heat shock protein expression of goat in Hainan high temperature season.16 adult Hainan Black goat with good health and approximate weight were randomly divided into 4 groups, fed with basal diet(control group), basal diet+0.5 mg/kg Se(Se group), basal diet+100 mg/kg VE(VE group), and basal diet+0.5 mg/kg Se+100 mg/kg VE(Se+VE group), respectively.The experimental period was 93 d.Semen samples were collected in the last week of the experiment on two consecutive days.The semen quality, antioxidant enzyme activities and heat shock protein expression were analyzed.The results showed that compared with control group, the ejaculate volume was not significantly affected by Se or VE supplement(P>0.05).Sperm density and sperm motility were increased significantly by Se and VE supplement(P<0.05), and the abnormal rate was decreased extremely significantly(P<0.01).The goats fed with Se and VE also had higher activities of GSH-Px(P<0.01), SOD(P<0.05), CAT(P<0.05) and T-AOC(P<0.01), and lower MDA concentration in seminal plasma(P<0.05).The relative expression levels of HSP70 and HSP90 mRNA in supplement groups were decreased extremely significantly(P<0.01).However, there were some certain differences between the Se and VE supplement groups on semen quality and heat shock protein expression.In conclusion, the supplementation of Se and VE could help to improve goat semen quality by increasing the sperm density, sperm motility, the antioxidant enzyme activities, and decreasing the abnormal rate in hot season of Hainan.Finally, Se and VE supplement had good effects on relieving the environment heat stress. 相似文献
213.
以新鲜小松菜为试材,采用小苏打复合液、乙酸锌复合液2种不同保绿途径对其冻藏前进行烫漂处理,并对小松菜钙、钠、锌元素含量进行测定,比较了2种不同前处理消解方法精确性,研究了不同处理方法对冻藏期小松菜相关品质指标的影响。结果表明:2种保绿途径均显著延缓了小松菜总叶绿素含量的损失(P0.05),不同程度增加了样品中钙、钠、锌离子含量,其中金属离子保绿途径的乙酸锌复合液处理样品的锌离子残留量超标,相比而言,碱保绿途径的小苏打复合液处理对冻藏期小松菜相关元素残留安全性及护绿效果较好,处理时应避免长时间、高温烫漂对产品硬脆度的破坏而抵消复合液中钙离子的保脆效应。 相似文献
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本研究旨在分析猪源ST9型耐甲氧西林金黄色葡萄球菌(Staphylococcus aureus,MRSA)中前噬菌体的流行情况、结构特点和转导能力,探究前噬菌体在猪源MRSA流行克隆形成中的作用。基于全基因组信息,分析了近年来从我国多省分离的131株ST9型MRSA中前噬菌体的流行率、分型、亲缘关系和结构特征;选取含不同分型前噬菌体的菌株进行诱导,对诱导获得的噬菌体颗粒进行转导,测定转导子的耐药表型及体外适应性。研究结果显示:猪源ST9型MRSA的前噬菌体携带率为78.6%(103/131株),其中,63株携带完整前噬菌体序列,所有前噬菌体序列均不含耐药基因,仅2.9%(3/103株)的前噬菌体序列含毒力基因;前噬菌体谱型丰富,其整合酶分型主要为Sa2int和Sa4int;各型别前噬菌体结构同源性较高,完整前噬菌体可被诱导为长尾噬菌体;噬菌体颗粒可包装供体菌的aadD、tet(L)耐药基因并转导至受体菌中;转导子可获得卡那霉素、四环素耐药表型,体外生长能力与受体菌株无明显差异(P>0.05)。研究结果表明:猪源ST9型MRSA的前噬菌体携带率较高,谱型丰富,不携带耐药基因,部分噬菌体可包装供体菌的耐药基因转导至受体菌,产生的适应性代价小。 相似文献
217.
对砌石拱坝的加高倍厚中新、老坝体结构面,用有限元软件ANSYS结合接触理论进行计算,并分析结果得出:温升、水压力和淤沙压力使结合面上的接触压力增大,从而接触摩擦应力较大,有利于结合面的结合,而结合面在温降的作用下有脱离的趋势。 相似文献
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Jinshajiang River, which has a drainage area of 485,100 Km 2, average flux of 142.9 billion m 3, and soil conveyance of 247 million t/a, is the largest branch of Changjiang river. It is also the largest soil resource of the Three Gorges reservoir and upper reach of Changjiang River. To research the development and trend of Jinshajiang sediment not only has a relation to Jinshajiang water resource strategy, but also has important meaning to control the silt in Three Gorges reservoir and the Changjiang water resource development. The paper statistically analyses the flux and sediment conveyance of the Pingshan station, which is the primary hydrological station in the Jinshajiang River Drainage Area. Through several non-parameter statistical methods such as Spearman order correlativity check, Kendell order correlativity check, and linear regression check, the paper concludes that the sediment evolvement trend of Pingshan station is not distinct. 相似文献