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为研究利用不同纯化浓缩方法制备的新城疫疫苗对SPF鸡免疫效果的影响,试验取经过纯化浓缩的新城疫抗原制备的疫苗、经离心未经浓缩的抗原制备成的疫苗和经浓缩未离心的抗原制备成的疫苗分别免疫30日龄SPF鸡,免疫后分别在第7d、14 d、21 d、28 d、35 d、45 d、70 d、90 d采集血清检测新城疫抗体水平。结果表明,经浓缩纯化后抗原制备的疫苗与其他两组抗原制备的疫苗相比,物理外观性状基本相同,浓缩纯化后抗原制备的疫苗其单位抗原含量更高、杂质更少,抗体水平更高,统计数据显示差异显著。因此研究得出,浓缩倍数(即抗原含量)越高,抗体水平越高,持续的时间也越长。 相似文献
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Terzić S Jemersić L Lojkić M Madić J Grom J Toplak I Sver L Valpotić I 《Veterinary research communications》2003,27(4):329-339
Ten pigs, aged 85 days, were vaccinated with a subunit vaccine containing 32 g of classical swine fever virus glycoprotein E2 (gp E2) (group 1), and a further 10 pigs were vaccinated with a C strain vaccine (104±0.15 TCID50/ml), produced by amplification in minipig kidney (MPK) cell culture (group 2). Nine non-vaccinated pigs served as a control group (group 3). Serum samples were collected before (day 0) and at 4, 10, 21 and 28 days after vaccination and were analysed by two commercially available enzyme immunoassays and by a neutralizing peroxidase-linked assay (NPLA). At the same times, peripheral blood was taken for determining the total leukocyte count and the body temperature was taken daily. Antibodies were not detected in serum samples collected before vaccination (day 0), and no side-effects that could be connected with vaccination were observed during the trial. Ten days after vaccination 6/10 pigs vaccinated with the subunit vaccine were seropositive. On days 21 and 28, the ratios of serologically positive to vaccinated pigs were 9/10 and 10/10, respectively. Four of the ten pigs that were vaccinated with the C strain vaccine were positive on day 21 and 9/10 on day 28. However, the results of the NPLA showed that only 4/10 pigs had an antibody titre >1:32 at the end of the trial in both the vaccinated groups, even though the subunit vaccine initiated an earlier and higher level of neutralizing antibodies than the vaccine produced from the C strain. Challenge was performed 28 days after vaccination on four randomly selected pigs from both vaccinated groups. The pigs survived the challenge without showing any clinical signs of classical swine fever (CSF), while two nonvaccinated control pigs died on the 10th and 12th days after infection. 相似文献
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本试验旨在研究布鲁菌侵染小鼠过程中一氧化氮(NO)的作用,以及NO和非对称性二甲基精氨酸(ADMA)在此过程的相互作用关系。以布鲁菌标准疫苗株M5侵染小鼠,首先用小鼠的血清进行虎红平板凝集(RBPT)和试管凝集试验(SAT),再用Griess试剂法和ELISA法测定对照组和侵染组不同组织和血清中的NO和ADMA含量,对小鼠肝脏和脾脏的各个侵染时间段进行CFU计数观察。结果显示,用布鲁菌M5侵染小鼠后,RBPT和SAT在14d时检测到有阳性反应。侵染组和空白对照组NO总含量上变化不大,但侵染组血清中的NO含量随时间出现下降,而肝脾中NO含量随时间出现上升,其他各组织NO含量波动不明显。而ADMA的总趋势与NO相反。CFU计数结果显示,小鼠肝脾内布鲁菌的数量在14d时一直处于增长状态,28d时布鲁菌的数量下降,表明布鲁菌的分裂繁殖和机体NO的含量存在一定的关系。 相似文献
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C. C. Whitehead 《The Veterinary quarterly》2013,33(3):150-157
Summary There are two metabolic disorders of major commercial importance in poultry that involve the occurrence of fatty deposits in the liver. Fatty Liver and Kidney Syndrome (FLKS) affects young birds and the main manifestations, lipid infiltrations into liver and many other organs, are apparently secondary effects of the primary lesion that lies in carbohydrate metabolism. Although several nutritional and environmental factors influence FLKS, the main factor is the vitamin, biotin. In the absence of an adequate supply of biotin, the hepatic activity of pyruvate carboxylase, a biotin‐dependent enzyme, becomes so low that gluconeogenesis in the liver via pyruvate becomes negligible. When the bird is then subject to a mild stress and 1or short term fasting, liver glycogen reserves become rapidly depleted and a progressive hypoglycaemia develops that ultimately proves fatal. Supplementing diets with adequate amounts of biotin can prevent the syndrome. Fatty Liver Haemorrhagic Syndrome (FLHS) is brought about by an excessive accumulation of fat in the livers of adult hens which weakens the cellular structure of the liver and allows fatal haemorrhaging to occur. The aetiology of the syndrome is not clear, but a major factor is an excessive intake of dietary energy. However, Me involvement of hormonal and toxicological factors, as well as other nutritional factors, is also possible. 相似文献
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将40只10日龄海兰褐蛋雏鸡,随机分成试验组和对照组,每组20只,分别皮下注射ND-La Sota弱毒疫苗0.2ml/只。同时给试验组雏鸡投服缓释复方免疫增强剂1粒/只,对照组不投服。在免疫前、免疫后10、20、30和40d,每组随机取10只鸡采血,测定ND-HI抗体效价、T淋巴细胞ERFC形成率和ANAE阳性率。结果免疫后10、20、30、40d,试验组与对照组比较,鸡ND-HI抗体效价、T淋巴细胞ERFC形成率和ANAE阳性率差异极显著(P〈0.01)或显著(P〈0.05),三项指标具有相同的消涨趋势,表明缓释复方免疫增强剂可以提高鸡的体液免疫功能和细胞免疫功能。 相似文献
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腐蹄病C型节瘤拟杆菌纤毛蛋白基因T程疫苗对家兔的免疫试验 总被引:1,自引:0,他引:1
将转化C型节瘤拟杆菌纤毛蛋白基因表达子粒的工程菌PAK/2pfsC在含羧苄青霉素营养肉汤培养基中培养,用MgCl2法在培养物上清中提取表达产物(纤毛蛋白).将表达的纤毛蛋白产物用弗氏完全佐剂乳化,制成疫苗.用疫苗免疫3只健康家兔,21 d后再次接种;定期采血,用对流免疫电泳和K凝集实验检测试验家兔的体液免疫应答及抗体水平.结果发现,免疫7 d即可产生相应抗体,21 d后抗体效价达到8 000×以上,而且高滴度抗体可维持6个月以上.试验表明,腐蹄病C型节瘤拟杆菌纤毛蛋白基因工程疫苗具有较好的免疫应答和免疫原性. 相似文献