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21.
为了解江苏常州地区肉鸡禽白血病病毒(ALV)感染情况,本研究采集了该地区2019年7-12月、2020年1-4月肉鸡血清样本1257份,通过ELISA试剂盒检测ALV-A/B、ALV-J、抗原p27阳性率。结果显示:在接受调查的两个地区均存在ALV感染及混合感染,且ALV-A/B感染率(13.13%)均高于ALV-J(5.01%);不同月份阳性率存在一定差异,ALV-A/B、ALV-J均为春夏季阳性率较高,秋冬季逐渐下降趋势;抗体阳性样本中有54.39%的p27抗原阳性率。本次调查为江苏常州地区商品肉鸡ALV净化及防控提供一定的参考依据。 相似文献
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作者综述了2008-2009年维生素在反刍动物中的研究进展。维生素A可提高反刍动物的免疫功能,影响反刍动物脂肪组织的发育,具有抗氧化作用;维生素D3能提高奶牛血浆中钙、磷水平,提高血清中25-(OH)D3的浓度,影响牛肉品质;维生素E能提高肉牛的生产性能、奶牛的产奶量,降低繁殖疾病的发病率,刺激生殖器官发育,改善繁殖性能。烟酸能提高牛的生产性能,提高T3、T4水平;叶酸和维生素B12合用能增加牛奶中乳糖、蛋白质及总固形物的产量;胆碱可缓解奶牛产后能量负平衡状态。 相似文献
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P.M.Y. Smets E. Meyer B.E.J. Maddens L. Duchateau S. Daminet 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2010,24(1):65-72
Background: Blood urea nitrogen and serum creatinine concentrations only detect a decrease of >75% of renal functional mass. Therefore, there is a need for markers that allow early detection and localization of renal damage.
Hypothesis: Urinary albumin (uALB), C-reactive protein (uCRP), retinol binding protein (uRBP), and N -acetyl-β- d -glucosaminidase (uNAG) concentrations are increased in dogs with chronic kidney disease (CKD) compared with healthy controls and in healthy older dogs compared with young dogs.
Animals: Ten dogs with CKD, 10 healthy young dogs (age 1–3 years), and 10 healthy older dogs (age > 7 years) without clinically relevant abnormalities on physical examination, hematology, biochemistry, and urinalysis.
Methods: Urinary markers were determined using an ELISA (uALB, uCRP, and uRBP) or a colorimetric test (uNAG). Results were related to urinary creatinine (c). The fixed effects model or the Wilcoxon rank sum test were used to compare the different groups of dogs.
Results: uALB/c, uRBP/c, and uNAG/c were significantly higher in CKD dogs than in healthy dogs. No significant difference was found for uCRP, which was not detectable in the healthy dogs and only in 3 of the CKD dogs. Between the healthy young and older dogs, no significant difference was detected for any of the markers.
Conclusion: The urinary markers uALB/c, uRBP/c, and uNAG/c were significantly increased in dogs with CKD compared with healthy controls. Additional studies are needed to evaluate the ability of these markers to detect renal disease before the onset of azotemia. 相似文献
Hypothesis: Urinary albumin (uALB), C-reactive protein (uCRP), retinol binding protein (uRBP), and N -acetyl-β- d -glucosaminidase (uNAG) concentrations are increased in dogs with chronic kidney disease (CKD) compared with healthy controls and in healthy older dogs compared with young dogs.
Animals: Ten dogs with CKD, 10 healthy young dogs (age 1–3 years), and 10 healthy older dogs (age > 7 years) without clinically relevant abnormalities on physical examination, hematology, biochemistry, and urinalysis.
Methods: Urinary markers were determined using an ELISA (uALB, uCRP, and uRBP) or a colorimetric test (uNAG). Results were related to urinary creatinine (c). The fixed effects model or the Wilcoxon rank sum test were used to compare the different groups of dogs.
Results: uALB/c, uRBP/c, and uNAG/c were significantly higher in CKD dogs than in healthy dogs. No significant difference was found for uCRP, which was not detectable in the healthy dogs and only in 3 of the CKD dogs. Between the healthy young and older dogs, no significant difference was detected for any of the markers.
Conclusion: The urinary markers uALB/c, uRBP/c, and uNAG/c were significantly increased in dogs with CKD compared with healthy controls. Additional studies are needed to evaluate the ability of these markers to detect renal disease before the onset of azotemia. 相似文献
26.
目的预测猪链球菌2型(SS2)溶血素(SLY)B细胞表位。方法以DNAstar分析为主,综合分析二级结构、亲水性、表面可及性及抗原性指数,辅以吴玉章氨基酸抗原指数计算方法进行SS2溶血素B细胞表位预测。结果推测最有可能的B细胞表位位于溶血素N端第74~85、231~244区域位。结论应用多参数预测SS2溶血素的特征,为表位疫苗的研制奠定了基础。 相似文献
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G. Fernandes de Queiroz M. Lúcia Zaidan Dagli S. Aparecida Meira J. Maria Matera 《Veterinary and comparative oncology》2013,11(3):230-235
This work aimed to evaluate serum vascular endothelial growth factor (VEGF) in 25 dogs with soft tissue sarcoma, and in 30 healthy dogs. Blood was collected once time from the control animals and three times, in the same way, from animals with sarcoma. Blood count was performed in the blood collected, and serum VEGF was measured by enzyme‐linked immunosorbent assay quantitative method. Serum VEGF in control animals was similar to patients with soft tissue sarcoma. There was a reduction in serum VEGF after the sarcoma resection. There was positive correlation between serum VEGF and neutrophil counts, and negative between VEGF and hemoglobin content in animals with sarcoma. Animals with hemangiopericytoma showed higher serum VEGF levels compared to the patients with malignant peripheral nerve sheath. Circulating blood cells can contribute to elevate VEGF serum concentrations in dogs with soft tissue sarcomas and a possible role of VEGF in the angiogenesis of these tumors. 相似文献
28.
表达大肠杆菌K88ac-ST1-LTB融合蛋白工程菌株的免疫原性研究 总被引:2,自引:0,他引:2
已构建的能表达大肠杆菌K88ac-ST1-LTB融合蛋白的工程菌株BL21(DE3)(pXKST3LT5)及其表达产物经动物试验证实没有毒性反应。用从IPTG诱导的工程菌中提取的包涵体或经甲醛灭活的工程菌制成抗原,免疫小鼠,结果免疫小鼠至少能抵抗2MLD的大肠杆菌强毒株C83902(K88ac,ST^ ,L^ )的攻击,用提取的包涵体免疫家兔后,采集的血清能够中和天然ST1的毒性,这表明构建的工程菌株BL21(DE3)(pXKST3LT5)可以作为预防幼畜大肠杆菌性腹泻基因工程菌苗的候选株。 相似文献
29.
Objective To determine a reference range for serum cobalamin concentration in healthy cats in Australia using a chemiluminescent enzyme immunoassay and to prospectively investigate the prevalence of hypocobalaminaemia in cats with non-alimentary tract disease.
Design Prospective study measuring serum cobalamin concentrations in clinically healthy cats and cats with non-alimentary tract illness.
Procedure Blood was collected from 50 clinically healthy cats that were owned by staff and associates of Veterinary Specialist Services or were owned animals presented to Creek Road Cat Clinic for routine vaccination. Blood was collected from 47 cats with non-alimentary tract illness presented at either clinic. Serum cobalamin concentration was determined for each group using a chemiluminescent enzyme immunoassay.
Results A reference range for Australian cats calculated using the central 95th percentile in the 50 clinically healthy cats was 345 to 3668 pg/mL. Median serum cobalamin concentration in 47 cats with non-alimentary tract illness (1186 pg/mL; range 117–3480) was not significantly different to the median serum cobalamin of the 50 healthy cats (1213 pg/mL, range 311–3688). Using the calculated reference range one sick cat with non-alimentary tract illness had a markedly low serum cobalamin concentration.
Conclusion Although hypocobalaminaemia is uncommon in sick cats with non-alimentary tract illness in Australia, its occurrence in this study warrants further investigation. 相似文献
Design Prospective study measuring serum cobalamin concentrations in clinically healthy cats and cats with non-alimentary tract illness.
Procedure Blood was collected from 50 clinically healthy cats that were owned by staff and associates of Veterinary Specialist Services or were owned animals presented to Creek Road Cat Clinic for routine vaccination. Blood was collected from 47 cats with non-alimentary tract illness presented at either clinic. Serum cobalamin concentration was determined for each group using a chemiluminescent enzyme immunoassay.
Results A reference range for Australian cats calculated using the central 95th percentile in the 50 clinically healthy cats was 345 to 3668 pg/mL. Median serum cobalamin concentration in 47 cats with non-alimentary tract illness (1186 pg/mL; range 117–3480) was not significantly different to the median serum cobalamin of the 50 healthy cats (1213 pg/mL, range 311–3688). Using the calculated reference range one sick cat with non-alimentary tract illness had a markedly low serum cobalamin concentration.
Conclusion Although hypocobalaminaemia is uncommon in sick cats with non-alimentary tract illness in Australia, its occurrence in this study warrants further investigation. 相似文献
30.
为探明2014年-2015年在福建省流行的羊传染性脓疱病毒(ORFV)遗传变异情况,对10株ORFV流行毒株的F1L、B2L和VIR基因进行克隆、测序及分析。结果表明,10株ORFV F1L基因之间的核苷酸序列同源性为97.6%~100%,与国内株的核苷酸序列同源性为96.8%~99.7%,与NZ2参考株的核苷酸序列同源性为96.3%~97.1%;同NZ2参考株比较,FJ-YT2014缺失2个氨基酸;10株ORFV B2L基因之间核苷酸序列同源性为97.5%~99.9%,与国内株的核苷酸序列同源性为96.7%~99.5%,与NZ2参考株的核苷酸序列同源性为96.7%~97.7%;10株ORFV VIR基因之间的核苷酸序列同源性为95.8%~99.5%,与国内株的核苷酸序列同源性为94.6%~99.6%,与NZ2参考株的核苷酸序列同源性为94.6%~96.4%。基于基因核苷酸序列的遗传进化分析表明,10株ORFV F1L基因与福建省分离株、山西株和新疆株亲缘关系较近;10株ORFV B2L基因与新疆、山西、德国毒株亲缘关系较近;10株ORFV VIR基因与台湾、新疆株亲缘关系较近。结果提示,当前福建省流行的ORFV F1L、B2L和VIR基因尚未出现明显变异,但是其F1L、B2L和VIR基因核苷酸序列之间普遍存在异质性。 相似文献