冷应激对海兰雏鸡某些血相变化的影响

采用100只雄性海兰雏鸡进行急性（24h以内）、慢性冷应激（低5℃）及冷适应实验，通过瑞氏染色和脂酶染色法观察外周血白细胞分类及T淋巴细胞数目的变化。结果表明：急性冷应激期间，嗜碱性细胞数目增加，异嗜性细胞／淋巴细胞（H／L）明显增加，应激24h后，淋巴细胞明显减少（P＜0．05），冷适应后淋巴细胞数目显著增加（P＜0．01）、T淋巴细胞数目极显著增加（P＜0．001）、H／L明显减少（P＜0．01）。结果提示低5℃冷应激使雏鸡细胞免疫水平增加。冷应激15d后雏鸡已经开始适应。     

重度冷应激对贵妃雏鸡部分消化器官肥大细胞数目的影响

笔者通过对切片中肥大细胞数目的观察及计数,研究在同一低温(低10℃)条件下不同时间段120只贵妃雏鸡部分消化器官肥大细胞数目的变化,结果发现,重度冷应激组相对于对照组数目增加,其中肝脏的急性应激组的2 h、4 h极显著增加(P0.01),24 h极显著减少(P0.01);腺胃急性应激组的4 h极显著增加(P0.01),24 h显著增加(P0.05)。十二指肠肌层15 d应激组极显著增加(P0.01),绒毛层4 h与15 d应激组显著增加(P0.05)。说明重度冷应激加强了贵妃雏鸡的局部消化能力。     

冷应激对白羽黑凤雏鸡外周血白细胞分类及T淋巴细胞变化的影响

选用190只黑凤健雏在较正常饲养温度低5℃和10℃的条件下进行急性、慢性冷应激及冷适应实验,通过瑞氏和酯酶染色法观察外周血白细胞分类及T淋巴细胞数目的变化,结果表明:在低于5℃实验中,H/L值在急性冷应激期间明显增加;T-淋巴细胞数目显著增加.在低于10℃实验中,H/L值变化规律同5℃实验组,T-淋巴细胞数目先增加后减少.冷适应后,低于5℃实验中,淋巴细胞数目明显升高,提示低5℃冷应激对提高黑凤雏鸡免疫水平是有利的.     

乳酸杆菌LA-LA-5对雏鸡溃疡性结肠炎的影响

为探究乳酸杆菌LA-5对雏鸡溃疡性结肠炎的预防及治疗作用,试验以1日龄SPF雏鸡为研究对象,连续灌服益生菌微胶囊3 d,在10日龄时用100 mg/kg体重的2,4,6-三硝基苯磺酸乙醇混合液灌肠,通过灌肠途径,建立2,4,6-三硝基苯磺酸诱导的雏鸡溃疡性结肠炎动物模型。对血液中白细胞总数、嗜酸性粒细胞和盲肠扁桃体中树突状细胞数量的变化进行较全面系统地检测,结果发现,乳酸杆菌LA-5组雏鸡白细胞总数和嗜酸性粒细胞数明显低于结肠炎模型组雏鸡,而树突状细胞数明显高于结肠炎模型组雏鸡,说明乳酸杆菌LA-5对雏鸡溃疡性结肠炎有一定的预防和治疗作用,为溃疡性结肠炎的预防和治疗提供了新的思路和理论依据。     

冷应激对贵妃雏鸡外周血白细胞分类及T淋巴细胞变化的影响

寒冷属于应激源之一,有关冷应激（cold stress）对免疫的影响已有许多研究。由于研究者们所采用的动物不同,应激的方式、强度、作用时间不同,所测指标不同,结果也不尽相同。笔者以前曾探讨了不同冷应激强度和作用时间对家禽免疫力的影响,但是对珍禽还未见相关资料报道。试验以贵妃雏鸡为研究对象来研究冷应激对其血相变化的影响,为研究冷应激对珍禽免疫力变化的影响提供试验数据。     

应用2-DE技术对冷应激前后雏鸡血清蛋白质表达谱的差异分析

为了比较冷应激前后雏鸡血清蛋白质组的差异,试验采取冷应激处理前后的雏鸡血清,经双向电泳(two-dimensional electrophoresis,2-DE),考马斯亮蓝染色后用PDQuest凝胶图像分析软件测定分析了雏鸡冷应激前后的血清蛋白质组。结果表明:冷应激前后雏鸡血清蛋白质组具有明显的差异表达;成功建立了雏鸡血清蛋白质双向电泳技术。     

中草药抗雏鸡冷应激机理的研究

选用附子、女贞子、干姜3味中草药,对雏鸡进行了慢性（5、10 d）冷应激（12±1）℃实验,通过NO、谷胱苷肽过氧化物酶（GSH-PX）、红细胞及白细胞数量变化探索中草药抗雏鸡冷应激的机理。结果表明,应用附子后雏鸡血清和下丘脑中NO含量显著下降（P〈0.01）,而GSH-Px活性、红细胞和白细胞数量显著升高（P〈0.01）。表明附子可使冷应激雏鸡NO含量、GSH-Px活性发生变化,具有明显抗冷应激的作用。     

冷应激对雏鸡十二指肠及血清NO代谢的影响

探讨冷应激对雏鸡十二指肠及血清NO代谢的影响。方法：以健康15日龄雏鸡为试验对象,进行急性和慢性冷应激（12＋1）℃处理,检测十二指肠和血清NO含量以及T—NOS和iNOS活性。结果：急性冷应激时十二指肠和血清NO含量、十二指肠T—NOS活性随应激时间的延长呈波动性变化;十二指肠、血清iNOS活性和血清T—NOS活性呈现先升高后降低的变化。慢性冷应激时,随着冷应激时间的延长NO含量先降低后升高,T—NOS活性先升高后降低,iNOS活性有所升高。急性和慢性冷应激可以引发雏鸡十二指肠和血清的NO代谢改变。     

蜱感染后兔体炎性细胞数量的变化

通过应用免疫增强剂或免疫抑制剂改变兔体的非特异性免疫功能,观察长角血蜱幼虫感染后兔体炎性细胞数量的变化,结果发现免疫增强组兔淋巴细胞和嗜中性粒细胞在长角血蜱幼虫感染前和感染后变化不大;免疫抑制组淋巴细胞数量降低,而嗜中性粒细胞数量增加;不用药组幼虫叮咬前与叮咬后相比淋巴细胞数量稍降低,嗜中性粒细胞数量稍增加,嗜酸性粒细胞、单核细胞和嗜碱性粒细胞数量变化不明显.     

蜱感染后兔体炎性细胞数量的变化

通过应用免疫增强剂或免疫抑制剂改变兔体的非特异性免疫功能，观察长角血蜱幼虫感染后兔体炎性细胞数量的变化，结果发现免疫增强组兔淋巴细胞和嗜中性粒细胞在长角血蜱幼虫感染前和感染后变化不大；免疫抑制组淋巴细胞数量降低，而嗜中性粒细胞数量增加；不用药组幼虫叮咬后相比淋巴细胞数量稍降低，嗜中性粒细胞数量稍增加，嗜酸性粒细胞、单核细胞和嗜碱性粒细胞数量变化不明显。     

Blood cells and plasma proteins of chickens fed a diet supplemented with (1-->3),(1-->6)-beta-D-glucan and enrofloxacin.

The effects of (1-->3),(1-->6)-beta-D-glucan from Saccharomyces cerevisiae and of the fluochinolone enrofloxacin were studied on red and white blood cells and plasma proteins of growing chickens up to the 35th day of life. The prominent findings within the leukocyte population on a per cent scale are: (i) increase of leukocyte count; increase of neutrophils and decrease of lymphocytes in the control and in the antibiotic group from day 17 to day 35; (ii) a minor decrease of neutrophils and no change of lymphocytes in the glucan group; (iii) the monocytes increase from 2.5 +/- 1.8% to 6.5 +/- 7.6% in the glucan group; (iv) the basophils increase in the control group and scale down in the other groups from day 17 to day 35. The total count of leukocytes increases in the controls and in the glucan group. The total protein content of blood plasma, beta-globulin and gamma-globulin increase and the albumin-globulin-ratio and alpha-globulin decline during chickens growth. These changes are most prominent in the glucan group. The haemoglobin concentration shows in all three dietary groups a highly significant increase from day 17 to day 35 by about 17 to 27 per cent; no changes are seen in packed cell volume and number of erythrocytes per litre blood.     

Changes in Numbers of Leukocytes in Immune Organs of Juvenile Coho Salmon after Acute Stress or Cortisol Treatment

Abstract

We examined the effects of acute stress and cortisol treatment on the number of leukocytes (normalized for fish body weight) in the blood, thymus, spleen, and anterior kidney of juvenile coho salmon Oncorhynchus kisutch. In acutely stressed or cortisol-fed fish, the numbers of leukocytes increased significantly in the thymus and anterior kidney, and decreased significantly in blood and spleen within 1 d after treatment. Numbers of cells in the anterior kidney, blood, and spleen returned to control levels by 3 d after treatment, but cell numbers in the thymus remained significantly greater than control values until 3–7 d after acute stress. Although dietary cortisol resulted in increased plasma cortisol titers and caused the same changes in leukocyte distribution as those caused by acute stress, the magnitude or duration of elevated cortisol levels and leukocyte numbers were not correlated. These results suggest that, although increased plasma cortisol titers induced by stress may be involved in the change in number of cells in various immune organs, factors other than cortisol are involved as well.     

冷应激对雏鸡下丘脑-垂体-甲状腺轴的影响

越来越多的证据表明,应激能够激活下丘脑-垂体-甲状腺轴,进而影响促甲状腺激素释放激素(TRH)、促甲状腺激素(TSH)及甲状腺激素的合成与分泌。为了探明冷应激对雏鸡下丘脑-垂体-甲状腺轴的影响,以公雏鸡为实验动物,进行急性(0.25、1、3、6、12h与24h)与慢性(5、10d与20d)冷应激处理(12±1)℃,检测了雏鸡下丘脑TRH mRNA的表达水平,血清TSH、FT(3T3的游离形式)及FT(4T4的游离形式)的含量。结果表明:急性应激时,TRH mRNA的表达水平在各应激时间点均显著升高,TSH变化不明显,FT3开始无变化,在6h时突然降低,而后又显著升高,FT4开始变化不大,6h后显著升高;慢性应激时,TRH mRNA的表达水平与相应的对照组相比显著降低,TSH变化仍不明显,FT3呈上升趋势,而FT4呈下降趋势。这说明冷暴露可以使雏鸡下丘脑-垂体-甲状腺轴的激素分泌发生改变,而且不同程度的冷应激对同一激素也会产生不同的影响。     

Homeothermic development of young scaleless chicks

Normal, scaleless, and artificially depilated chicks were exposed for 30 min to an ambient temperature of 11° C when 3 to 14 d old and their cloacal temperatures recorded every 15 min. The three groups of chicks demonstrated a greater resistance to cooling as a function of increased age, but both depilated and scaleless chicks develop this ability at a significantly slower rate than normal birds. Scaleless chicks are no more resistant to acute cold stress as they mature than comparable chicks without their normal body insulation.     

Response of leukocytes in chickens infected with the avian schistosome Austrobilharzia variglandis (Trematoda)

Leukocyte levels were monitored weekly in chickens infected with the avian schistosome Austrobilharzia variglandis. Changes in relative and absolute numbers of leukocytes were recorded over a 7-week period beginning 1 week before exposure. There was a significant increase (P less than 0.001) in total leukocytes, peaking at 5.8 X 10(4) cells/mm3 on day 21 postexposure; controls had 2.4 X 10(4) cells/mm3 on that day. The leukocyte count declined over the next 3 weeks, returning to nearly normal levels by day 42 postexposure. With the exception of eosinophils, which peaked 35 days postexposure, all leukocyte subpopulations peaked in number on day 21. Increases in heterophils and monocytes were related to the schistosome egg burden.     

Canine differential leukocyte counting with the CellaVision DM96Vision, Sysmex XT-2000iV, and Advia 2120 hematology analyzers and a manual method

Background: For differential leukocyte counts, automated blood smear evaluation systems have been too slow or inaccurate to replace or supplement the manual differential count. The CellaVision DM96Vision (DM96V), a new instrument, is an automated image analysis system that is rapid and accurate enough to be used for enumerating human leukocytes and may be useful for analysis of canine blood. Objectives: The aims of this study were to evaluate the performance of the DM96V in differential counting of canine leukocytes, to compare its performance with that of other methods, and to analyze interoperator variability. Methods: Four methods of determining the leukocyte differential count of 108 canine blood samples were compared based on agreement, precision, and errors as well as relative performance. Differential counts were obtained using the DM96V, the manual method, and automated methods performed by the Advia 2120 and Sysmex XT‐2000iV. Results: All leukocyte types were detected by the DM96V and the manual method, and all 4 methods had similar mean and median results in most cases. The automated methods were more precise than either the DM96V or manual method when comparing identification of a single type of leukocyte, especially neutrophils and lymphocytes. However, precision of the automated methods was only fair for monocytes, and the Advia and Sysmex failed to identify basophils. The Advia reported fewer monocytes and eosinophils than did the other methods. Significantly fewer lymphocytes were identified by the manual method than by the Sysmex, Advia, and DM96V. The DM96V occasionally presented duplicate images of the same neutrophils. Conclusions: The CellaVision DM96V is a satisfactory system for facilitating canine differential leukocyte counting. The DM96V differential count was more similar to the manual count than to automated counts, which were more precise but had errors and omissions in detecting some types of leukocytes.     

Correlation of hematological changes and serum and monocyte inhibition with the early suppression of phytohemagglutinin stimulation of lymphocytes in experimental infectious bursal disease.

Several experiments were conducted to study the mechanism of infectious bursal disease virus induced suppression of phytohemagglutinin stimulation of peripheral blood lymphocytes. Infectious bursal disease virus inoculation of one week old chicks resulted in significant suppression of phytohemagglutinin stimulation during the first three days after inoculation as demonstrated by a whole blood assay. Mild thymic necrosis was seen on day 3. Hematological changes during this time consisted of increased numbers of circulating lymphocytes and monocytes in infected chickens. Absolute monocyte counts remained elevated even after phytohemagglutinin stimulation had returned to normal. Furthermore, even after a 72.3% reduction in the monocyte population in leukocyte preparations, there was still marked viral induced suppression of phytohemagglutinin stimulation. An elevation in the absolute number of circulating large immature lymphocytes correlated with suppression of phytohemagglutinin stimulation. Sera from infected and control chickens depressed phytohemagglutinin stimulation of lymphocytes from control chickens at the 5 and 10% concentration. At the 1% concentration, inhibiton by control sera was considerably less than the inhibition by infected sera. The relationship between these findings and the mechanism of viral induced suppression of T-lymphocyte function is discussed.     

Influence of chronic caprine arthritis-encephalitis virus infection on the population of peripheral blood leukocytes

The influence of caprine arthritis-encephalitis (CAE) virus infection on the population of peripheral blood leukocytes in goats was evaluated. For this purpose two groups of adult dairy female goats were formed. The experimental group consisted of 17 goats, which had been naturally infected for many years. The control group comprised 29 non-infected goats, which originated from CAE-free herd. All goats were clinically healthy. Whole blood was collected and tested in hematological analyzer and light microscope to assess the total number of leukocytes and the percentage of four leukocyte populations--neutrophils, eosinophils, monocytes and lymphocytes. Then, flow cytometry with monoclonal antibodies against several surface antigens (namely CD14, CD2, B-B2, CD4, CD8h, TCR-N6, WC1-N2 and WC1-N3) was performed to assess the proportion of lymphocyte subpopulations. Statistically significant differences (alpha < or = 0.01) were observed only in the subpopulations of T lymphocytes--percentage of all subpopulations were significantly higher in the group of seropositive goats. No statistically significant differences were revealed with respect to the total number of blood leukocytes, the average percentage of blood leukocyte populations and proportions of both T and B lymphocytes.     

Peripheral leptin effect on food intake in young chickens is influenced by age and strain

The acute effect of leptin on the regulation of food intake was investigated in layer and broiler chickens. In an initial study, we observed that a single intraperitoneal injection of recombinant chicken leptin (1 mg/kg BW) dramatically reduced (38%) food intake in 56-day-old layer chickens, more moderately reduced (15%) food intake in 9-day-old layer chicks, and had no significant effect in 9-day-old broiler chicks. In a subsequent study, body weight and plasma concentrations of leptin were measured weekly in layer and broiler chicks from day 1 to 35 of age and brain leptin receptor and neuropeptide Y (NPY) mRNA expression were analyzed at 1, 9, and 35 days of age. At day 1 of age, peripheral concentrations of leptin were significantly greater in layer than broiler chicks. Subsequently, despite increases in body weight and differences in growth rates between layer and broiler chicks from day 8 to day 35 of age, peripheral concentrations of leptin were constant and similar in both genotypes. Leptin receptor and NPY mRNA were expressed in brain from day 1 in chicks of both genotypes and increased significantly to day 35 of age. These observations provide evidence that the inhibitory effect of leptin on the regulation of food intake in growing chicks is an age dependent process. Furthermore, acquisition of the anorectic effect of leptin is likely to be associated with greater expression of the leptin receptor and NPY mRNAs than to changes in blood levels of leptin. Finally, this study provides evidence that chickens selected for high growth rates may be less sensitive or responsive to peripheral concentrations of leptin than chickens with low growth rates (layers), suggesting that the faster growth of broiler chicks may be related to a lessened responsiveness to anorexigenic factors.