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61.
The effect was studied of an acute and non-persistent hyperglycaemia on the serum fructosamine and blood glycated haemoglobin concentrations in canine samples. Five dogs were given glucose solution intravenously and blood samples were taken from each dog before and at 5, 15, 30, 60 and 120 min and 24 h after the infusion. There was an intense hyperglycaemia 5 min after the injection was given, but no statistically significant differences in the serum fructosamine and glycated haemoglobin were observed. It was concluded that an acute and transient hyperglycaemia does not cause significant changes in the glycated haemoglobin and fructosamine concentrations in healthy dogs.  相似文献   
62.
在保存家蚕突变基因资源过程中调查发现:黄血蚕蛾翅在羽化之初呈鲜黄色,白血蚕均不然。通过与白血蚕(非黄翅)和黄血抑制基因(I)进行杂交试验,分析黄翅的遗传规律,结合普查家蚕突变系统蛾翅色性状,证明黄翅性状与幼虫黄脚一样,为黄血基因支配。进而记录了因黄血基因的多效作用在卵、幼虫、茧、成虫各阶段表现的形态特征。  相似文献   
63.
Whole blood has been compared with erythrocytes and plasma for spectrophotometric cholinesterase determination in the dog. Cholinesterase activity was characterized using two substrates: acetylthiocholine and butyrylthiocholine. Acetylcholinesterase was the only form of cholinesterase present on erythrocytes and hydrolysed only acetylthiocholine. Butyrylcholinesterase (pseudocholinesterase) was predominant in plasma, hydrolysing mainly butyrylthiocholine. Based on these results, a method based on the use of two substrates (acetylthiocholine for monitoring acetylcholinesterase and butyrylthiocholine for determining butyrylcholinesterase) in the same whole blood sample is recommended for canine cholinesterase analysis. This way of monitoring both enzymes can be easily automated, yielding good within (CVs < 5%) and between-run (CVs < 7%) precision.  相似文献   
64.
铬对泌乳期奶牛的生产性能和主要生理指标的影响   总被引:6,自引:0,他引:6  
研究了泌乳期奶牛日粮中添加吡啶羧酸铬或赖氨酸铬对其生产性能和血液主要生理指标的影响。选择75头泌乳前期(〈80d)的荷斯坦奶牛随机分为试验组A、B和对照组C。试验组A和B每天日粮中分别补充吡啶羧酸铬和赖氨酸铬,供试期间对照组C不添加有机铬。结果表明:铬可提高泌乳期奶牛的生产性能,增强和改善泌乳奶牛的免疫力和应激状态。试验组A和试验组B泌乳量高于对照组C(P〈0.01);试验组B血清中的甘油三酯的浓度低于对照组C(P〈0.05);试验组A血清中胰岛素浓度低于对照组C(P〈0.01);试验组A和试验组B血清中葡萄糖浓度都高于对照组C(P〈0.01);试验组A和试验组B血清中皮质醇的浓度分别比对照组C低7.21nmol/L和4.92nmol/L,试验组A和试验组B血清中IgG的浓度分别比对照组C高2.1g/L和3.1g/L。  相似文献   
65.
本试验对白萨福克羊(White Suffolk)和特克塞尔羊(Texel)的6项生理指标、10项生化指标按冬春季、夏季和秋季三个不同阶段进行了全面测定。白萨福克羊和特克塞尔羊的生理指标随季节变化而变化。白萨福克公、母羊夏季的体温和呼吸极显著高于冬春季、秋季的体温和呼吸,特克塞尔公、母羊夏季的体温和呼吸极显著高于冬春季的体温和呼吸(P<0.01);两个品种公、母羊各种类型的白细胞变化均在正常范围内。两个品种羊在秋季和冬春季葡萄糖含量都较高,略高于藏羊含量,是对寒冷适应性的表现;血液钙水平较高,表明对较高海拔的代谢适应性。  相似文献   
66.
Hosam J. Al-Tamimi   《Livestock Science》2007,106(2-3):254-260
Unlike poikilotherms, homeotherms resist wide amplitudes of core body temperature (Tcore) fluctuation when exposed to reasonably variant ambient temperature (Ta) extremes. The degree of cold/heat thermotolerance varies tremendously amongst mammalian species. Thermotolerance can be partially inferred by the extent of resistance in body temperature displacement from normothermia when subjected to thermal stress. Regulation of thyroid calorigenic hormones is primarily contingent upon thermal homeostasis. Thyrosuppression generally exacerbates cold stress and hence may be a useful tool to examine the extent of cold-tolerance. An experiment was conducted to examine the extent of cold-tolerance on artificially goitrous Black Bedouin goats. Ten goat kids (initial Avg. BW = 30.6 ± 0.4 kg) were fitted with two miniature temperature data loggers, intraperitoneally and subcutaneously to identify core (Tcore) and subcutaneous (Tsq) temperature responses, respectively, to chronically (47 days) cold (< 10 °C) environment along with or without oral administration of the thyreostat propylthiouracil (PTU 20 mg/kg BW/day). Five animals served as controls (CON) whereas the remaining five were treated with PTU for 31 out of the overall 47-day observation period. Despite its 74.5%-evoked transient depression of circulating free thyroxine (FT4), PTU-treatment failed (P > 0.10) to cause significant displacements in Tcore or Tsq as compared to CON values throughout the 52-day trial period. As a function of Ta, Tcore − Tsq thermal gradient revealed a significantly (P < 0.01) linear regression (r2 = 0.41), to indirectly infer a graded blood redistribution from peripheral to splanchnic vascular beds with the fall in Ta. In the light of the current findings, it can be deduced that– in addition to the fact that it is superior in terms of heat-tolerance– the Black Bedouin goat is also profoundly cold-tolerant. Furthermore, our recently developed technique in concurrently recording Tcore and Tsq proves efficient and feasible to simultaneously record temperatures of different body sites in free-roaming animals, thereby overcoming potentially erroneous artifacts caused by frequent experimenter intrusion.  相似文献   
67.
采用垂直板高pH值不连续聚丙烯酰胺凝胶电泳对21只杜泊羊的血红蛋白(Hb)、转铁蛋白(Tf)、白蛋白(Alb)、前白蛋白(Pa)和慢α2球蛋白(Sα2)5个基因座的多态性进行了分析。结果表明杜泊羊的Hb、Tf位点存在多态性,Hb位点共检测到HbA和HbB2个等位基因,构成HbAA、HbBB、HbAB3种基因型,其中HbBB和HbB为优势基因型和优势基因;Tf位点共检测到TfDD、TfCC、TfBD、TfCD4种基因型,受TfB、TfC、TfD3个复等位基因控制,其中TfCC、TfDD基因型和TfC、TfD基因为优势基因型和优势基因。试验未在Alb、Pa和Sα2位点检测出多态性,它们均呈现单态。  相似文献   
68.
AIM:To study the isolation,expansion and purification of mesenchymal stem cells (MSCs) from human umbilical cord blood (UCB),and investigate some biological identities of MSCs.METHODS:(1) MSCs of UCB,adult bone marrow (BM) and fetus BM were isolated by centrifugation with Ficoll,and the different kinds of MSCs were observed everyday.(2) Surface markers of MSCs were identified by flow cytometry.(3) The level of HGFs (TPO,SCF,FLT-3L,IL-6) secreted by different sources of MSCs was checked by ELISA method.RESULTS:(1) No difference in morphology of the colonies between UCB MSCs and BM MSCs was observed.However,the mononuclear cells needed in culture of UCB MSCs was about 3 times more than that in culture of BM MSCs.The times of UCB MSCs colony formation and confluencing were longer than that of BM in primary culture.(2) After passaged,there was no significant difference in the proliferation rates of 3 kinds of MSCs.Only 4 of 15 UCB samples contained a homogeneous population of MSCs.(3) UCB MSCs shared the same markers with BM MSCs.Neither hematopoietic marker nor immunologic recognition antigens were expressed.(4) The level of hematopoietic growth factors (HGFs) secreted by 3 kinds of MSCs was similar.CONCLUSIONS:(1) MSCs were isolated from UCB,but the amount of MSCs in UCB was smaller than that in BM,and just seldom samples of UCB contained homogeneous MSCs.(2) MSCs from UCB and BM shared the same biological characteristics,such as proliferation ability,surface markers,immunophenotypes and HGFs secretion.  相似文献   
69.
The antioxidant status of the red blood cells of buffaloes (n = 20) suffering from post-parturient haemoglobinuria (PPH) was assessed by comparing their tocopherol (vitamin E) and reduced glutathione contents with those of red blood cells from apparently healthy buffaloes (n = 20). The red cell tocopherol content of the diseased buffaloes (1.76±0.11 g/ml) was significantly (p<0.01) lower than that of healthy buffaloes (2.45±0.14 g/ml). This may be the first report comparing the concentration of tocopherol in the red blood cells of buffaloes suffering from PPH and apparently healthy buffaloes.There was a drastic reduction in the reduced glutathione content in the red cells of haemoglobinuric buffaloes (23.74±2.86 mg%) compared to the healthy control buffaloes (73.71±3.87 mg%). The diseased buffaloes also exhibited severe hypophosphataemia. These findings suggest that an impaired or insufficient antioxidant potential of the red blood cells in this disease in buffaloes is associated with the phosphorus deficiency.  相似文献   
70.
An enzyme-linked immunosorbent assay to detect thyroglobulin autoantibodies (TGAB) in canine serum was developed and validated. The test result for each sample was derived from the optical density readings (OD) and expressed as an Ab-score(%) calculated from three in-house calibrators. The assay specifically detected TGAB as judged from lack of response in the assay after samples had been incubated with specific antigen. Intra- and interassay coefficients of variation ranged from 2.0–4.9% and 4.6–9.9%, respectively. The detection limit, an Ab-score of 5.6%, was close to the median Ab-score of 10% observed in healthy dogs (n = 132). The median Ab-score of dogs with primary hypothyroidism and lymphocytic thyroiditis (n = 11), skin diseases (n = 35), and non-thyroidal diseases (n = 63) was 340%, 12%, and 8%, respectively. The prevalence of TGAB in hypothyroid dogs with lymphocytic thyroiditis (sensitivity) was 91% (95% confidence limits: 59%–99%). In dogs with dermatological diseases without lymphocytic thyroiditis the prevalence of TGAB was 3% corresponding to a specificity of 97% (95% confidence limit: 85%–100%). In dogs with non-thyroidal diseases and healthy dogs the prevalence of TGAB was 5% and 6%, respectively. The diagnostic accuracy of serum TGAB was evaluated by subjecting the data from 11 dogs with lymphocytic thyroiditis and 35 control dogs without lymphocytic thyroiditis to receiver-operating characteristic curve analysis. The area under the receiver-operating characteristic curve (W = 0.966; 95% confidence limit 87%–100%) was significantly higher than that of a worthless test (0.5) (P < 0.0001), thereby indicating that serum TGAB measurements distinguished between dogs with and without lymphocytic thyroiditis.  相似文献   
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