首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
The acute effects of an extract of Sesbania drummondii were assessed in vitro on the smooth muscle contractility of intestine and lung parenchyma in the chicken and aortic arch in the rat. Dose-response contraction curves for histamine, carbachol, and norepinephrine were obtained in the ileal, parenchymal, and aortic strips, respectively. After washing was completed, the strips returned to baseline tensions and then were incubated for 10 minutes with an ethyl acetate extraction fraction of S drummondii (molecular weight less than 500). Dose-response curves to the same agonists were repeated at the end of the incubation period. Contractile responsiveness of chicken ileum was little affected by acute incubation of the tissue with the extract. Comparison with the great inhibition of in vitro ileal contractility seen previously in chickens with chronic toxicosis indicated that intestinal inhibition was not due to acute effects of sesbania, but required time for a toxic metabolite to be formed or for damage to occur from affected vasculature. Contractile responsiveness of chicken lung parenchyma to histamine (10(-5) M and 10(-4) M) was significantly decreased, as was rat aortic responsiveness to norepinephrine (10(-7) M to 10(-4) M). Responses in parenchyma were not as greatly inhibited as those in tissue from animals with chronic toxicosis. Greatest inhibition of contractility was seen in the vascular strips, indicating that vascular inhibition has a role in pathologic changes. To test the vasculature inhibition effect in vivo, anesthetized, catheterized rats were given 100-microliter aliquots of dilutions of the extract, IV.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

2.
Atracurium besylate, a nondepolarizing neuromuscular blocking agent, was administered to 24 isoflurane-anesthetized domestic chickens. Birds were randomly assigned to 4 groups, and atracurium was administered at dosage of 0.15, 0.25, 0.35 or 0.45 mg/kg of body weight. The time of onset of twitch depression, the amount of maximal twitch depression, and the duration of muscular relaxation were recorded. After return to control twitch height, atracurium was further administered to achieve > 75% twitch depression. When twitch depression reached 75% during noninduced recovery, 0.5 mg of edrophonium/kg was administered to reverse the muscle relaxation. Throughout the experimental period, cardiovascular, arterial blood gas, and acid-base variables were monitored. The effective dosage of atracurium to result in 95% twitch depression in 50% of birds, (ED95/50) was calculated, using probit analysis, to be 0.25 mg/kg, whereas the ED95/95, the dosage of atracurium to result in 95% twitch depression in 95% of birds, was calculated by probit analysis to be 0.46 mg/kg. The total duration of action at dosage of 0.25 mg/kg was 34.5 +/- 5.8 minutes; at the highest dosage (0.45 mg/kg), total duration increased to 47.8 +/- 10.3 minutes. The return to control twitch height was greatly hastened by administration of edrophonium. Small, but statistically significant changes in heart rate and systolic blood pressure, were associated with administration of atracurium and edrophonium. These changes would not be clinically relevant. In this study, atracurium was found to be safe and reliable for induction of muscle relaxation in isoflurane-anesthetized chickens.  相似文献   

3.
1. The pharmacokinetic properties of doxycycline were determined in healthy chickens and chickens naturally infected with Mycoplasma gallisepticum after a single intravenous (i.v.) and oral administration of the drug at 20 mg/kg body weight. Tissue residues of the tested drug after an oral dose of 20 mg/kg given twice daily for 5 consecutive days were also estimated in diseased chickens. 2. The plasma concentrations of doxycycline following single i.v. and oral administration were higher in healthy chickens than in diseased ones. Following i.v. injection, the elimination half-life (t1/2beta), distribution half-life and mean residence time (MRT) were longer in healthy chickens than in diseased birds. The values of total body clearance (ClB) and volume of distribution (Vdss) were larger in healthy chickens than in diseased birds. 3. After single oral administration, the absorption half-life (tl/2ab) and the elimination half-life were longer in normal birds than in diseased ones. The maximum plasma concentration of the drug was higher in normal chickens than in diseased ones. 4. Following repeated oral administration, the concentration of doxycycline in all tissues except muscle was higher than the corresponding concentrations in plasma. Concentrations of doxycycline in different tissues were in the following order: kidney > liver > lung > muscle. The drug was detected in liver and kidney in substantial concentrations on d 5 post administration of the last dose whereas, on d 7, its concentration in all tissues was below the lower limit of the sensitivity of the assay method used. Because of the low sensitivity of the microbiological assay method used in this study, a safe withdrawal time for doxycycline in diseased birds could not be estimated for the meanwhile.  相似文献   

4.
1. A total of 336 Hubbard Hi-Y broiler hybrids were fed from d 1-41 on diets based on maize or wheat and barley which were supplemented (or not) with 100 mg/kg plant extract consisting of capsaicin, cinnamaldehyde and carvacrol. 2. Body weight was not enhanced, but feed conversion improved by 4.2% on the maize diet and 2.0% on the wheat and barley diet. 3. Plant extract addition enhanced the breast muscle proportion of empty body weight by 1.2% in comparison to control birds. 4. The apparent ileal digestibility of nutrients (crude protein, fibre and amino acids) was not significantly better in birds fed on supplemented diets than in the control group. 5. Reduction of E. coli, Clostridium perfringens and fungi and increase of Lactobacillus spp. were observed in the 41-d-old chickens from the supplemented groups. 6. An increase in the lipase activity in pancreas and intestine wall was found in older birds fed on the plant extract supplemented diets.  相似文献   

5.
将260只28日龄试验鸡(体质量215~230 g)随机分成5组:健康对照组20只,甲磺酸达氟沙星溶液静注给药组和内服给药组、甲磺酸达氟沙星脂质体静注给药组和内服给药组,每组60只。以5 mg/kg体质量剂量分别采用静脉注射和内服2种给药途径给予健康蛋雏鸡甲磺酸达氟沙星溶液和脂质体混悬液,于给药后0.167、0.333、0.5、0.75、1、1.5、2、4、6、9、12、24 h各剖杀5只鸡,取血液、肝脏、肾脏、肺脏和肌肉样品。采用反相HPLC色谱内标法测定各组织中达氟沙星浓度。应用MCPKP分析软件处理血浆药物浓度-时间数据,比较2种剂型的组织药动学参数。结果显示,与溶液组相比,甲磺酸达氟沙星脂质体组肝脏、肺脏中的药物分布明显提高,肾脏中的分布降低;通过相对摄取率、靶向效率和峰浓度比3个靶向指标的对比,脂质体组明显提高了肺部靶向性,且在肺部有一定的缓释作用。  相似文献   

6.
Cyanide detoxification is catalysed by two enzymes: rhodanese [thiosulphate: cyanide sulphurtransferase, E.C. 2.8.1.1], and 3-mercaptopyruvate sulphurtransferase [3-MST, EC. 2.8.1.2]. In the present work, the activity of the two enzymes in the crude extracts of different tissues and in the mitochondrial and cytosolic fractions of tissues from some ruminants (camels, cattle and sheep) and birds (chickens and pigeons) have been compared. Rhodanese activity was almost exclusively present in the mitochondrial fraction. In ruminants and chickens the highest activity of rhodanese was found in the liver, followed by the kidney. In pigeons, however, the enzyme activity was the highest in the kidneys. In camels' tissues, the rhodanese activity was significantly (P < 0.05) lower than in cattle or sheep, and the enzyme activities in the two latter species were similar. The activity of 3-MST in the crude extract of tissues from camels was similar to that in sheep, but higher than that in cattle. The enzyme activity was equally distributed between the mitochondrial and cytosolic fractions in the liver and kidneys of camels, cattle and sheep.  相似文献   

7.
C/O specific pathogen-free White Leghorn chickens were intracerebrally inoculated at one day of age with a brain homogenate of Japanese bantams (Gallus gallus domesticus) affected with fowl glioma. Histologically, six of eight inoculated chickens developed nonsuppurative meningoencephalitis in cerebrum and two of them had the characteristic lesions of fowl glioma. Hyperplastic lymphoid foci concomitantly developed in many organs of these birds, especially in the heart. Apart from these lymphoid foci, lymphocytic myocarditis was observed in all inoculated birds. Matrix inclusions were also noted in myocardial cells. Immunohistochemically, avian leukosis virus antigens were detected in reticular cells in the lymphoid foci, mesangial cells of the kidney, smooth muscle cells of the blood vessels, and myocardial cells. Of these tissues, the myocardium of all inoculated birds consistently showed strong reactivity for this antigens. The matrix inclusions were also positive for the antigens. These results suggest that the causal virus of fowl glioma has a high propensity to replicate, especially in myocardium and nonsuppurative myocarditis occurs associated with so-called fowl glioma.  相似文献   

8.
The plasma and tissue pharmacokinetics of marbofloxacin in chickens experimentally infected with Mycoplasma gallisepticum and Escherichia coli were studied. Marbofloxacin was given to 66 infected chickens by oral administration at a dosage of 5 mg/kg b.w., once a day for three days. Plasma, brain, kidney, liver, lung, muscle and trachea were collected and marbofloxacin concentrations were analyzed by a high performance liquid chromatography method. In the infected chickens, maximal marbofloxacin concentrations in plasma, brain, kidney, liver, lung, muscle and trachea were 1.84, 1.33, 7.35, 5.61, 3.12, 2.98, and 4.51 g/mL (g); the elimination half‐lives of marbofloxacin were 6.8, 2.74, 9.31, 8.45, 9.55, 11.53 and 5.46 h for plasma, brain, kidney, liver, lung, muscle and trachea, respectively. AUC were calculated to be 9.68, 8.04, 45.1, 27.03, 20.56, 19.47, and 32.68 μg/mL (g) ·h for plasma, brain, kidney, liver, lung, muscle and trachea, respectively. Marbofloxacin concentration in tissues except for brain exceeded marbofloxacin concentration in plasma, with AUCtissue/AUCplasma ranging from 2.01 to 4.66 and Peaktissue/Peakplasma ranging from 1.62 to 3.99. The results showed that a marbofloxacin dosage of 5 mg/kg administered orally at 24 h intervals may provide successful treatment of chicken with MG and E. coli infection.  相似文献   

9.
1. Disposition kinetics of doxycycline (doxy) was studied in healthy chickens and chickens experimentally intoxicated with aflatoxin B1 by intravenous, oral or intramuscular (i.m.) injection, in a single dose of 15 mg/kg body weight. In addition, the tissue distribution and residual pattern of the drug were determined in healthy and intoxicated chickens. 2. The maximum serum concentrations of doxy were reached 1.97 and 2.37 h after oral, and 1.57 and 2.92 h after i.m. dosage in healthy and aflatoxic birds, respectively. 3. The volumes of distribution and total body clearances were higher in aflatoxic birds (1.75 l/kg and 14.61 ml/kg/min) than in healthy chickens (0.93 l/kg and 4.6 ml/kg/min). Data relating to intravenous injection were analysed using a two-compartment open model curve fit. 4. Lower values of systemic bioavailability were observed in intoxicated birds (30.9 and 33.9%) than healthy ones (43.7 and 57.3%) after oral and i.m. administration, respectively. 5. The highest concentration of doxy residues were present in liver, kidney and serum followed by heart and muscles. Doxy residue concentrations in edible tissues was below the EEC limit 6 d after cessation of oral or i.m. medication with 15 mg/kg body weight twice daily for 5 successive days.  相似文献   

10.
Chin RP 《Avian diseases》2002,46(2):447-452
Thirty-eight cases were identified in which a nonfermentative, gram-negative, rod-shaped bacterium was isolated from the respiratory system of turkeys and chickens. Cases were submitted from various parts of the country. Preliminary assessment of phenotypic characteristics indicated this bacterium was different from common pathogenic or opportunistic bacteria isolated from the avian respiratory tract. Most cases reported a history of respiratory distress and/or increased flock mortality. Lesions seen in infected birds included tracheitis and pneumonia, which correlate with the sites of isolation. Sixty-one percent of the isolations were made from the trachea and 25% from the lung. Age of infected birds ranged from 35 to 315 days in turkeys and 53 days to 3 yr in chickens. In most instances (90%), other bacteria were also isolated from affected sites. The significance of this organism in respiratory disease in birds is unknown.  相似文献   

11.
本试验采用单因子试验设计,将144羽1日龄健康、体重均一的低脂系肉仔鸡随机分为两组,每组6个重复,每个重复12羽。对照组饲喂基础日粮,试验组饲喂添加0.125%五味子提取物组的基础日粮,试验期为8周,研究五味子提取物对低脂系肉仔鸡肉质的影响。结果表明:(1)与对照组相比,五味子提取物组肉仔鸡胸肌纤维密度显著提高,腿肌直径显著降低(P0.05),腿肌纤维密度有升高趋势,胸肌直径有降低趋势;(2)与对照组相比,五味子提取物组胸肌和腿肌的水分、蛋白质与脂肪含量无显著差异(P0.05);(3)五味子提取物显著降低了肉仔鸡胸肌和腿肌剪切力(P0.05),胸肌和腿肌pH、红度(a*)、黄度(b*)有升高趋势(P0.05),滴水损失和蒸煮损失有降低趋势(P0.05)。  相似文献   

12.
The lesions and etiologic agents associated with 13 outbreaks of respiratory disease in commercial chickens were investigated. Adenoviruses were isolated from tracheal and lung tissues of affected chickens in all 13 outbreaks. Escherichia coli was isolated from the lung of an occasional bird. The tracheal specimens were consistently negative for Bordetella avium, but E. coli and occasionally Staphylococcus aureus were isolated. There was also serological evidence in one outbreak, and pathological evidence in another, of a concurrent infectious bursal disease virus (IBDV) infection of chickens affected with the disease. Gross and microscopic alterations in the tracheas and lungs of affected chickens were similar in all outbreaks and consisted of catarrhal tracheitis and occasionally multifocal pneumonia with mononuclear cell infiltrates. Hepatitis and splenitis with heterophil infiltrates occasionally were seen in birds with coliform septicemia. The tracheal and lung lesions in the present investigation were considered primarily of adenovirus etiology, complicated by secondary bacterial infection.  相似文献   

13.
The effect of lignin supplementation to a diet contaminated with zearalenone (ZEA) on antioxidant status was studied in female chickens of the ISA BROWN laying strain. From the day of hatching to 2 weeks of age, four groups of chickens were fed the same uncontaminated control diet. After 14 days, Group 1 (control) continued to receive the uncontaminated diet, while Group 2 was fed an identical diet enriched with 0.5% chemically modified lignin. Simultaneously, chickens of Group 3 were switched to a diet contaminated with 7.9 mg/kg ZEA and those of Group 4 to an identical contaminated diet supplemented with 0.5% lignin. At 6 weeks of age blood and tissue samples were collected. Feeding of a diet contaminated with a high level of ZEA resulted in elevated glutathione peroxidase (GPx) activity in the duodenal mucosa and kidney tissues, and an increased γ-glutamyltransferase (GGT) activity in the plasma, indicative of oxidative stress. In the liver tissue, no mycotoxin-induced response in GPx and thioredoxin reductase (TrxR) activities occurred, and the malondialdehyde (MDA) level was even reduced. Neither the plasma levels of retinol and α-tocopherol nor the activities of superoxide dismutase in erythrocytes and GPx in blood were affected in birds fed the contaminated diet. The only effect of lignin supplemented to the contaminated feed was that it prevented the increase of GPx activity in the duodenal mucosa as an indicator of oxidative stress.  相似文献   

14.
The study was conducted to determine the effect of a lignocellulose supplemented diet on apparent ileal and total tract digestibility of fat and fatty acids (FA) in broiler chickens. A total of 48 21‐day‐old male Ross 308 chickens were divided into four treatment groups (n = 12) with six replicates per treatment. From 21 to 42 days of age, the broilers were fed experimental diets varied in the amount of lignocellulose: 0%, 0.25%, 0.5% and 1%. Total excreta were gathered during the last 3 days of the feeding trial and digesta was collected from the ileum at 42 days of the bird age. Digestibility was determined by the indicator method. The ether extract content in diet/digesta/excreta was determined by the gravimetric method, and fatty acid methyl esters were analysed by gas chromatography–mass spectrometry. Fat digestibility measured to the end of the small intestine and in the whole gastrointestinal tract in birds was high and exceeded 90% and 87% respectively. Addition of lignocellulose (1%) increased (p < 0.05) ileal fat digestibility but had no significant effect on total tract fat digestion. Absorption of total fatty acids (TFA) as well as myristic (C14:0), palmitoleic (C16:1) and α‐linolenic (C18:3n?3) acids, estimated by both methods, was significantly higher in birds fed the diets supplemented with lignocellulose, especially at a dose of 1%. Total tract absorption of some dietary polyunsaturated fatty acids (PUFA) (C20:2, C20:4n?6) was significantly lower from diet supplemented with 0.5% and 0.25% lignocellulose. There was observed a decrease in apparent digestibility of fat and most examined fatty acids, when measured between terminal ileum and total gastrointestinal tract. The results suggest that lignocellulose can affect digestion and FA absorption in broilers but, as the effect of lignocellulose was not studied previously, further investigations are necessary to confirm the results of the present experiment.  相似文献   

15.
采用以野菊花、穿心莲、柴胡等10味中药提取的中药制剂,连续给22日龄SPF鸡口服5 d后,以禽流感病毒H9N2、新城疫病毒F4、传染性支气管炎病毒强毒株M41和支原体S6强毒分别攻击,观察SPF鸡临床症状、发病率、病理学变化和分离病毒。结果表明,此中药制剂75 mg/只口服组,新城疫病毒、禽流感病毒和传染性支气管炎病毒攻击后发病率分别为12.5%,0%,10%;37.5 mg/只剂量口服组发病率分别为50%,10%,10%,且低剂量组病毒分离阳性。攻击支原体后,以上两个剂量组SPF鸡病变指数分别3.5和5.5,研究证实本中药制剂可以控制以上4种病原所致的家禽呼吸道病的发生。  相似文献   

16.
Serum antibody responses and haemolytic complement activity were evaluated in White Leghorn (WLH) and Rhode Island Red (RIR) chickens that were vaccinated with live-attenuated vaccines of Newcastle disease virus, or infectious bronchitis virus, or infectious bursal disease virus by means of ocular challenge at 10 times the normal vaccination dose. Complement titres in non-vaccinated birds were significantly higher in WLH birds compared to RIR birds. The lentogenic viral infection resulted in an immediate stimulation of complement activity, followed by a decrease to initial complement levels within 2 weeks post vaccination, when the antibody response took over immune defence. As compared to WLH chickens, RIR birds mounted a faster and significantly higher antibody response to the vaccine viruses used. In WLH hens, significantly higher haemolytic complement activity post vaccination was found as compared to RIR hens. Possible consequences of the observed differences in immune responsiveness of the two breeds to viral vaccines are discussed.  相似文献   

17.
1. The effects of dietary conjugated linoleic acid isomers (CLAs) on productive traits, carcase yield and meat quality were investigated in Beijingyou (Chinese) chickens. A total of 360 male chicks were allocated to 5 dietary treatments (0.00, 0.25, 0.50, 1.00 and 2.00% CLA) and fed for 126 d. 2. The results showed that CLA supplementation did not significantly influence body weight, but increased feed conversion and decreased intramuscular fat in breast and thigh muscles. Mortality was significantly higher in the control group. 3. The addition of 1.0 and 2.0% CLA decreased abdominal fat percentages. At CLA dietary levels greater than 0.5%, lipoprotein lipase activity in plasma was significantly decreased. 4. Hunter L* and a* values were not significantly affected by CLA supplementation. However, Hunter b* values were lower in chickens supplemented at levels greater than 0.5% CLA. Supplementing diets with CLA modified the fatty acid composition of breast muscle. The proportions of CLA, saturated and polyunsaturated fatty acids were increased whereas the proportion of monounsaturated fatty acids was decreased.  相似文献   

18.
Lesions of right heart failure and ascites in broiler chickens   总被引:2,自引:0,他引:2  
A naturally occurring cardiomyopathy in broiler chickens from a single Ontario farm was studied in order to define the morphologic changes. Gross and histologic features of affected birds were compared with those in age-matched control penmates. Body weight and weight and volume of individual cardiac chambers were measured. Histologic sections of 18 different tissues were examined, and lesions observed were scored subjectively. Affected birds were stunted and had marked right ventricular dilation and hypertrophy, atrial hypertrophy, ascites, pulmonary congestion and edema, and hepatic capsular fibrosis. Microscopic changes in the heart of affected birds were mild and did not suggest a specific cause of heart failure. Lungs had marked hypertrophy of parabronchial smooth muscle and collapse and apparent loss of associated air capillaries. Other histologic changes observed were thought to be the result of passive congestion of viscera caused by right heart failure and chronic debility. Although the specific etiology of this condition could not be determined, it was felt that this syndrome was unlikely to have been the result of any of the commonly recognized causes of congestive heart failure and ascites in broilers.  相似文献   

19.
马立克强毒MDV-GA对BWEL-SPF鸡的感染试验   总被引:1,自引:1,他引:0  
134只1日龄BWEL-SPF鸡随机分成2组,攻毒组84只腹腔注射2 000 PFU的MDV-GA细胞毒0.2 mL,对照组50只注射同等剂量的病毒稀释液。结果显示,攻毒后27 d攻毒组鸡只开始发病并持续到攻毒后51 d,发病高峰期在攻毒后28~42 d。经过60 d的观察发现,该毒株可以引起很高的肿瘤发生率(61.90%),死亡率为75.00%。肿瘤主要出现在肾脏、心脏、肝脏、性腺、脾脏、肺、胸腺、皮肤、腺胃等组织,其中以肾脏、心脏、肝脏、性腺、脾脏肿瘤发生率较高,分别为:36.90%,28.75%,25.00%,21.43%,17.86%。其中2个以上组织发生肿瘤的个体占44.08%;3个以上组织发生肿瘤的个体占27.38%。多数肿瘤个体同时伴有胸腺、法氏囊萎缩,脾脏、性腺肿大等症状。经过对发病鸡的肾脏作组织切片观察,发现其基本结构已经消失,伴随大量的淋巴细胞和浆细胞浸润,呈现典型的马立克症状。结果表明,利用2 000 PFU的MDV-GA毒株感染BWEL-SPF鸡可以得到大量的肿瘤样本,可用于探讨马立克淋巴瘤内部的基因变化。  相似文献   

20.
旨在探讨管花肉苁蓉醇提物对大鼠血液生化指标及心血管功能的影响,为管花肉苁蓉对心血管功能不全的辅助治疗作用提供现代医学研究佐证。将24只大鼠随机分为低、中、高剂量组和对照组,分别灌胃0.1、0.2、0.3 g/(100 g·BW)的管花肉苁蓉乙醇提取物和同体积的生理盐水,连续给药30 d。试验结束时,测定并比较各给药组与对照组的主要血液生化指标、心血管功能相关酶和激素水平、脏器系数以及颈动脉平滑肌的运动指标。结果表明,低剂量管花肉苁蓉醇提物显著提高大鼠血清ALT含量(P〈0.05),但低、中、高剂量管花肉苁蓉醇提物对其他血液生化指标影响均不显著(P〉0.05);对大鼠3种心肌酶活力的影响不显著(P〉0.05);低、中剂量组的Ang-Ⅱ水平显著低于对照组(P〈0.05),但EPO活力、ALD水平的变化不显著(P〉0.05);对大鼠的增重率、脏器系数影响不显著(P〉0.05),对颈动脉平滑肌运动指标有一定的降低趋势(P〉0.05)。综上提示,总体来看,管花肉苁蓉醇提物对大鼠的血液生化指标及心血管功能有一定的影响。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号