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41.
360只商品代Abor Acre肉用公鸡随机分为2组,每组4个重复,对照组金霉素的添加量为0mg/kg,处理组金霉素的添加量为150mg/kg,研究金霉素对肉仔鸡肠道微生物、血氨、尿酸和生产性能的影响。每隔7d检测肉仔鸡直肠和空肠中大肠杆菌、乳酸菌和双歧杆菌的变化情况,每隔2检测血液中氨和尿酸含量,每隔2周记录肉仔鸡体重和饲料消耗。试验结果表明,150mg/kg的金霉素对肉仔鸡的生长显著的促进作用,在3以前促进生长作用极显著(P<0.01),3周之后作用显著(P<0.05);在33日龄前,对直肠中的大肠杆菌具有显著的抑制作用(P<0.05),之后抑制作用消失(P>0.05),对空肠中大肠杆菌的抑制作用在19日龄前显著(P<0.05),之后作用消失(P>0.05);在12日龄前,对直肠和空肠中乳酸菌具有明显抑制作用(P<0.05),之后作用消失(P>0.05);对直肠和空肠中双歧杆菌均无显著影响(P>0.05);极显著降低35日龄以前肉仔鸡血氨浓度(P<0.05),之后作用效果降低,但仍显著(P<0.05);在21日龄前,显著降低血液尿酸含量(<0.05),49日龄时作用效果不显著(P>0.05)。研究表明,金霉素以低剂量、持续在饲料中添加时,对肉仔鸡的生长和采食具有显著的促进作用,这种促进作用与其抑制肠道中大肠杆菌、延缓肠道微生物的定植过程,以及降低血氨浓度有关。金霉素对肠道微生物的影响因菌种不同而有明显差异,而且对大肠杆菌不产生永久性抑制。血液尿酸含量的降低说明金霉素具有促进肉仔鸡氮沉积的作用。  相似文献   
42.
牦牛血清氟含量测定   总被引:1,自引:0,他引:1  
采用氟离子选择电极对37头青海牦牛血清氟含量进行测定,结果为0.015±0.007(0.005-0.026)mmol/L。同时还对该方法的准确度、精密度做了检测。  相似文献   
43.
Abstract— Humoral antibody responses to experimental Sarcoptes scabiei var. vulpes infection in 10 beagle dogs were demonstrated by an ELISA in three experiments. In the first experiment, four dogs, infected with a relatively high dose of S. scabiei, seroconverted 2 weeks post infection. All four animals showed clinical signs of sarcoptic mange. In the second experiment, six dogs were infected with a relatively low dose of S. scabiei. Three of the dogs developed clinical signs of sarcoptic mange and only in these three were antibodies to S. scabiei demonstrated. Seroconversion occurred 4–5 weeks post infection. The six dogs infected with a low dose of Sarcoptes were re-infected with a relatively low dose of mites 7 weeks after the spontaneous clinical recovery of the three dogs that had exhibited mange following the primary infection. The later three dogs showed a specific antibody response within 1 week and the other three dogs within 2 weeks following the re-infection. Resumen En tres experimentos se demostraron las respuestas humorales de anticuerpos a la infección con Sarcoptes scabiei var. vulpes en 10 perros de la raza Beagle por medio de pruebas ELISA. En el primer experimento cuatro de los perros infectados con una dosis relativamente alta de Sarcoptes, seroconvirtieron 2 semanas despues de la infección. Estos cuatro animales mostraban cuadro clínico de infección. En un segundo experimento seis de los perros se sometieron a una dosis relativamente baja del ácaro. Solo tres de estos perros demostraron cuadro clínico de la infección, y en éstos animales exclusivamente se encontraron anticuerpos de S. scabiei. Cinco o seis semanas después de la infección se produjo la seroconversión de los mismos. Los seis perros infectados con una dosis baja se volvieron a re-infectar con otra dosis relativamente baja siete semanas después de la recuperatión clínica espontánea de los tres perros que habían padecido el cuadro clínico de la sarna, después de la infección previa. Los últimos tres perros produjeron una respuesta de anticuerpos específica en una semana, y los otros tres perros en dos semanas después de la infección.  相似文献   
44.
青海黄牛血清运铁蛋白多态性研究   总被引:2,自引:1,他引:1  
采用聚丙烯酰胺凝胶电泳法对100头青海黄牛的血清运铁蛋白多态性进行了研究。结果发现:青海黄牛血清运铁蛋白位点存在TF ̄A,TF ̄B,TF ̄D1,TF ̄D2,TF ̄F,TF ̄E6个等位基因,总共构成13个基因型。与国内12个品种黄牛的遗传距离和聚类分析表明,青海黄牛与蒙古牛的亲缘关系最近(Dm=0.1178)。  相似文献   
45.
通过对禽霍乱菌苗免疫产蛋母鸡的血清和蛋黄的抗体定时检测后发现,免疫母鸡的血清抗体和蛋黄抗体的升降趋势基本一致(r=0.94),但后者较前者迟后3~6d;血清抗体和蛋黄抗体的滴度分别在加强免疫后的1~3d和3~6d都有不同程度下降,加强免疫前的滴度越高,免疫后的滴度下降幅度越大;蛋黄抗体水平普遍比血清抗体水平低,两者间的差异极显著(P<0.01),这可能是与禽多杀性巴氏杆菌本身的主要抗原成分(TI抗原)在鸡体内主要产金IgM有关。  相似文献   
46.
The aim of this study was to evaluate an enzyme-linked immunosorbent assay (ELISA), for determination of serum thymidine kinase 1 (sTK1) activity in dogs with malignant lymphoma (ML) and compare it with a thymidine kinase (TK) radioenzymatic assay (TK-REA). The TK-REA has recently been shown to be useful in determining the clinical stage and prognosis in canine ML. In addition, serum lactate dehydrogenase (LDH) was measured. Forty-five dogs were included in the study. Sixty serum samples from these dogs, stored in a tumour serum sample bank (stored at -20 degrees C), were analysed. Apart from 37 dogs with ML, four normal dogs as well as two dogs with mammary carcinomas, one dog with bladder carcinoma, and one dog with malignant fibrous histiocytoma were included. Staging of ML was based on the modified World Health Organization (WHO) staging system for canine ML. The diagnosis of all tumours was verified by histopathology. The TK activity (units per litre [U/L]) ranged from 1.0 to 607.9 in the TK-REA analysis and from 1.1 to 510 in the TK-ELISA (normal reference value <7U/L). The range for LDH was between 12 and 1194 U/L (normal reference value <228 U/L). There was a significant correlation between the TK-REA and the TK-ELISA. The correlation coefficient (CC) was 0.97 and the standard error of the estimate (SEE) was 3.7 U/L. There was no correlation between LDH and either the TK-REA or the TK-ELISA (CC=0.53 for both assays; SEE=26.7 and 12.7 U/L, respectively). Most of the variation in LDH was still within the normal reference range. The mean LDH in dogs with high-stage (stage IV+V) disease was 201.9 U/L. The corresponding values for the TK-REA and TK-ELISA were 109 and 109.9 U/L, respectively. The significant relation between the TK-REA and the TK-ELISA was confirmed by Bland-Altman analysis. The TK-ELISA assay, because of its relative simplicity, will permit measurement of TK in cases of ML in dogs to become a routine procedure.  相似文献   
47.
The aim of the study was to determine the intraarticular serum amyloid A (SAA) response pattern in horses with inflammatory arthritis. Inflammatory arthritis was induced by injection of lipopolysaccharide (LPS) into the radiocarpal joint of four horses. Serum and synovial fluid (SF) samples were collected before and at 4, 8, 12, 24, 48, 72, 96, and 144 h after injection. Concentrations of SAA were measured by immunoturbidometry, and expression of SAA isoforms was visualized by denaturing isoelectric focusing and Western blotting. The LPS injection caused systemic and local clinical signs of inflammation. Serum amyloid A appeared in serum and SF within 8 h after LPS injection. Isoelectric focusing showed three major SAA bands with apparent isoelectric points (pI) of 7.9, 8.6, and >9.3 in serum and SF. Synovial fluid contained two additional isoforms with highly alkaline apparent pI values (apparent pI value extrapolated from standard curve = 10.0 and 10.2), which were not present in any of the serum samples. In conclusion, intraarticular injection of LPS induced systemic and local inflammatory responses in the horses. By demonstrating SF-specific SAA isoforms the results of the present study suggest that SAA is synthesized locally in the equine inflamed joint, similar to what has been demonstrated in humans previously. The marked local SAA synthesis suggests an important pathophysiological role in inflammatory arthritis.  相似文献   
48.
49.
青海省湟源县本地黄牛四项血清钙指标的测定   总被引:2,自引:0,他引:2  
对30头湟源县本地黄牛的4项血清钙指标进行了测定。结果表明:犊牛的血清总钙、血清结合钙和血清游离钙含量均显著高于成年牛(P<0.01),而两者的血清游离钙百分率相似(P>0.05)。  相似文献   
50.
Daily fluctuations of cortisol concentration in the blood or saliva have been repeatedly reported. However, several contradictions in the existing literature appear on this subject. The present study was performed to definitively establish options for testing adrenocortical function. To the best of our knowledge, this is the first study to evaluate parallel circadian rhythms in salivary and serum cortisol concentrations during a 24-h period. Twenty horses were examined under the same conditions. Blood and saliva samples were taken every 2 h for 24 h to determine the daily changes in cortisol concentrations of saliva and serum at rest and to determine the relationship between salivary and serum cortisol levels. Cosinor analysis of group mean data confirmed a significant circadian component for both serum and salivary cortisol concentrations (P < 0.001 in both cases). The serum cortisol circadian rhythm had an acrophase at 10:50 AM (95% CI, 10:00 AM–11:40 AM), a MESOR of 22.67 ng/mL, and an amplitude of 11.93 ng/mL. The salivary cortisol circadian rhythm had an acrophase at 10:00 AM (95% CI, 9:00 AM–11:00 AM), a MESOR of 0.52 ng/mL, and an amplitude of 0.12 ng/mL. We found a significant but weak association between salivary and serum cortisol concentrations; the Pearson correlation coefficient was 0.32 (P < 0.001). The use of salivary cortisol level as an indicator of hypothalamic-pituitary-adrenal axis activity may be warranted. However, the salivary cortisol levels are more likely to be correlated with free plasma cortisol than with the total plasma cortisol concentration.  相似文献   
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