MDV对雏鸡血浆MDA含量与SOD活性的影响

为探讨丙二醛(MDA)和超氧化物歧化酶(SOD)在雏鸡马立克病(MD)发病过程中的作用,研究了雏鸡在人工攻毒后血浆MDA含量与SOD活性的动态变化.结果表明,攻毒组接种马立克病病毒(MDV)后第14天,血浆中MDA的含量显著高于对照组(P＜0.05),第7天和第28天高于对照组,第56天时基本接近;血浆中SOD活性在第7天时对照组显著高于攻毒组(P＜0.05),第14天和第28天高于攻毒组,但差异不显著.表明雏鸡在感染MDV后血浆中MDA含量显著升高,SOD活性明显降低,对雏鸡MD的发病诊断有重要的指导作用.     

感染“白点病”番鸭抗氧化功能的变化

用“白点病”病毒人工感染雏番鸭，于感染后第1、3、5、7、10和14d测定了雏番鸭血浆中丙二醛(MDA)的含量、超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)的活性。结果，雏番鸭感染“白点病”病毒后血浆中MDA的含量、SOD和GSH-Px活性发生明显变化，其中攻毒组雏番鸭在攻毒后第3d MDA含量开始升高，第5和第10d显著高于对照组；攻毒组雏番鸭SOD活性在攻毒后第3d开始显著低于对照组，随后在低于或显著低于对照组的范围内波动；GSH-Px的活性在攻毒后第7d开始下降，攻毒后第10d攻毒组显著低于对照组。提示，自由基可能在雏番鸭“白点病”的发病过程中起关键作用。     

淫羊藿多糖对雏鸡抗氧化功能的影响

为了观察不同浓度的淫洋藿多糖(EPS)对正常罗曼雏鸡血清中超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、过氧化氢酶(CAT)、谷胱甘肽还原酶(GR)活性及丙二醛(MDA)含量的影响,将80只1日龄健康罗曼雏鸡随机分为4组,每组20只。分别于1日龄皮下注射生理盐水以及不同浓度的EPS,连续注射7 d,分别在第7、14、21、28、35、42天采血,测定血清中SOD、GSH-Px、CAT、GR的活性及MDA含量。结果显示,使用EPS后,各试验组血清SOD、GSH-Px、CAT、GR活性均显著升高(P0.05),MDA含量均显著降低(P0.05),表明EPS可提高雏鸡的抗氧化能力。     

肠炎沙门菌感染对鸡血清SOD、GSH-Px活性及MDA含量的影响

研究通过检测鸡感染肠炎沙门菌(SE)后血清中超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)活性及丙二醛(MDA)含量的变化,探讨氧化损伤与SE感染的关系。将90只1日龄肠炎沙门菌阴性SPF鸡随机分为两组,对照组40只接种PBS,试验组50只接种肠炎沙门菌菌液。分别于接种后第1、3、7、14及21天进行屠宰,收集血清,检测血清中SOD、GSH-Px活性以及MDA含量的变化。结果显示:接种后第1、3、7及21天,试验组SOD及GSH-Px活性均显著高于对照组(P0.05),试验组及对照组中MDA含量差异不显著;组内不同时间点间比较表明,SOD、GSH-Px活性及MDA含量均存在波动性。由结果可知,肠炎沙门菌感染后鸡血清SOD、GSH-Px活性增强,提高了机体抗氧化能力和清除过氧化物的能力,保护了细胞免受损伤。同时血清SOD、GSH-Px活性及MDA含量波动变化表明机体对SE感染的氧化损伤调控具有时效性。     

硒缺乏对雏鸡空肠黏膜中SOD活性和MDA含量的影响

将40只1日龄雏鸡随机分为两组(n=20),对照组,饲料硒含量为0.40 mg/kg,试验组,饲料硒含量为0.01 mg/kg。分别与试验的第7天、21天、35天处死雏鸡并取空肠黏膜(各时间点均为6只),测定其中超氧化物歧化酶(SOD)活性和丙二醛(MDA)含量。结果表明,与对照组相比,第7天试验组空肠黏膜中SOD活性显著低于对照组(P<0.05),MDA含量无明显变化。第21天试验组空肠黏膜中SOD活性极显著高于对照组(P<0.01),MDA含量显著高于对照组(P<0.05)。第35天试验组空肠黏膜中SOD活性极显著低于对照组(P<0.01),MDA含量极显著高于对照组(P<0.01)。这表明,硒缺乏会降低雏鸡空肠黏膜中SOD的活性和提高MDA的含量。     

复方中药对热应激肉鸡血液自由基影响的研究

将14日龄肉鸡60羽随机均分为3组:常温对照组、热应激对照组和试验组,试验组与热应激对照组饲养条件相同,试验组饲料中添加1%复方中药。3个组肉鸡定期采血,测定血清GSH-Px、SOD的活性和MDA的含量。结果表明:与正常对照组相比,热应激对照组肉鸡血清GSH-Px、SOD活性下降,MDA含量则上升,其中血清GSH-Px活性显著降低,MDA的含量显著增加(P<0.05)。结果表明,复方中药能提高正常肉鸡血清GSH-Px、SOD活性,降低MDA的含量,对抗热应激所致的肉鸡血清GSH-Px、SOD活性下降和MDA含量升高(P<0.05或P<0.01)。提示本复方中药具有较显著抗自由基损伤的作用,能有效地清除体内过多的自由基。     

中药组方对汞中毒鸡抗氧化功能的影响

为了研究中药组方对试验性鸡汞中毒抗氧化功能的影响,试验分成空白对照组、阳性对照组和中药治疗组,于第20,40,60天时对试验鸡采血,采用酶联免疫吸附法(ELISA)测定血清中丙二醛(MDA)的含量,超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、天门冬氨酸氨基转移酶(AST)的活性。结果表明:阳性对照组鸡第60天血清中MDA的含量、AST的活性极显著高于空白对照组(P0.01),SOD、GSH-Px活性极显著低于空白对照组(P0.01);中药治疗第60天,血清中MDA的含量、AST的活性与阳性对照组比较极显著降低(P0.01),SOD、GSH-Px的活性与阳性对照组比较极显著升高(P0.01)。说明中药能增加血清中SOD、GSH-Px的活性,降低MDA的含量、AST的活性,减少氧化损伤。     

免疫与未免疫鸡感染MDV后血液部分指标及血浆MDA含量与SOD活性的动态变化

为探讨丙二醛(MDA)和超氧化物歧化酶(SOD)在鸡马立克氏病发病过程中的作用机制,研究了经火鸡疱疹病毒疫苗(HVT疫苗)免疫和未免疫的1日龄健康罗曼雏鸡在感染马立充氏疱疹病毒(MDV)后血液部分指标及血浆MDA含量与SOD活性的动态变化.结果表明:攻毒后外周血液红细胞数(RBC)、白细胞数(WBC)、红细胞压积(PCV)、网织红细胞比例(RCC)和血红蛋白含量(Hb)均呈上升趋势,非免疫攻毒组(Ⅱ组)和免疫攻毒组(Ⅲ组)的WBC、RCC和PCV明显高于非免疫对照组(C组)和免疫对照组(Ⅰ组),Ⅱ和Ⅲ组的RBC和Hb明显低于C和Ⅰ组,Ⅰ和Ⅲ组的RBC和WBC低于C和Ⅱ组,Ⅱ组的PCV除了在第7天显著高于C组外,其余均无显著差异;免疫组(Ⅰ和Ⅲ组)血浆MDA含量在攻毒后第7天低于非免疫组(C和Ⅱ组),第14天后便高于或显著高于非免疫组;而免疫组血浆SOD活性在攻毒后第7天低于或显著低于非免疫组,第14天后免疫组和非免疫组之间无显著差异.表明雏鸡感染MDV后血细胞的发育成熟受阻,而免疫对红细胞的发育成熟和白细胞的生成具有促进作用;同时发现雏鸡血浆中MDA含量的降低与SOD活性的提高对雏鸡抗MDV感染有增强作用.     

黄芪多糖对鸡抗氧化功能的影响

目的:观察不同浓度的黄芪多糖(APS)对正常罗曼雏鸡血清中SOD、GSH-Px、CAT、GR活性及MDA含量的影响。方法:将80只1日龄健康罗曼雏鸡随机分为4组,每组20只。分别于1日龄皮下注射生理盐水以及不同浓度的APS(12.5 mg/mL、25 mg/mL、50 mg/mL),0.2 mL/只,连续注射7 d,分别在第7、14、21、28、35、42天采血,测定血清中SOD、GSH-Px、CAT、GR的活性及MDA含量。结果:使用APS后,雏鸡血清SOD、GSH-Px、CAT、GR活性均显著升高(P0.05),MDA含量均显著降低(P0.05)。结论:APS可提高鸡的抗氧化能力。     

人工感染鸡传染性法氏囊炎病毒对机体抗氧化功能的影响

将80只21日龄AA肉鸡,随机分为试验组和对照组,每组各40只。试验组在接种传染性法氏囊病毒(IBDV)后57小时发病,鸡只表现典型临床症状,而对照组无异常变化。每组各抽取10只鸡,测定血清、肝脏和肾脏的超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活性和丙二醛(MDA)含量。结果表明:试验组与对照组比较,血清、肝脏和肾脏的SOD和GSH-Px活性降低(P<0.05)、MDA含量升高(P<0.05)。结论:鸡只感染传染性法氏囊病毒时,机体的抗氧化功能发生了改变。     

白虎定喘口服液药效研究

为验证新兽药白虎定喘口服液的药效作用,进行了鸡传染性支气管炎病毒（infectious bronchitis virus,IBV）鸡胚增殖抑制试验、气管纤毛运动试验及SPF雏鸡人工感染IBV疗效试验。将试验药液与等量IBV液混合作用后,接种11日龄SPF鸡胚,37℃孵育168 h,取存活鸡胚肾脏进行IBV的RT-PCR检测,结果表明,药物组168 h鸡胚存活率为80%,阳性对照组为20%,两组间差异显著（P<0.05）;试验药物组RT-PCR检测无目的条带出现,而阳性对照组有目的条带出现。40日龄SPF鸡连续用药3 d后,气管内注入0.02 mL墨汁,测量1 min内墨汁移动的距离,结果表明药物组墨汁移动距离极显著大于生理盐水对照组（P<0.01）。17日龄SPF鸡用IBV-M41滴鼻,0.3 mL/只,24 h后开始灌服药液,1 mL/kg,连用5 d,结果表明,试验药物组与攻毒对照组在临床症状计分、痊愈率上均存在显著差异（P<0.05）;试验组气管黏膜组织切片未见明显病变,而阳性对照组有明显病理变化。以上试验结果表明,白虎定喘口服液对IBV具有较好的体外抑制作用,可显著促进气管纤毛的运动,对鸡传染性支气管炎（IB）具有较好的临床防制效果。     

Isolation of avian infectious bronchitis virus from experimentally infected chickens.

Virus was recovered from the faeces of chickens infected at three or four weeks of age for more than 20 weeks after infection with commercial vaccines or with the T strain of avian infectious bronchitis virus (IBV). Virus was not recovered from the trachea, liver, spleen, bursa or kidneys of T strain infected birds longer than 29 days after infection at which point IBV was recovered from the bursa of a single infected bird. In a subsequent experiment IBV was recovered from the caecal lymph nodes and faeces of one of five birds 14 weeks after infection with a commercial vaccine but no virus was isolated from the trachea, kidneys, duodenum, bursa, ovaries or testes of any of the five birds at this time.     

板芩桔甘合剂对传染性支气管炎病毒人工感染雏鸡的临床疗效分析

旨在探讨板芩桔甘合剂（BQJGHJ）对传染性支气管炎病毒（IBV）人工感染雏鸡的临床疗效。选取120只雏鸡随机分为空白组、模型组（感染病毒）、阳性药物组（感染病毒+甘胆口服液）和BQJGHJ高、中、低剂量组（感染病毒+BQJGHJ）,每组20只。除空白组外,其他组感染IBV造模,4 d后,各组分别饮水给药,连用5 d。每天观察各组雏鸡临床症状,记录临床症状记分,统计有效率、治愈率;在造模后,给药第3、5天,及停药后第2天分别自翅下静脉采集血液,分离血清,ELISA法检测感染雏鸡血清中IFN-γ、IL-6、IL-10含量变化。结果显示：BQJGHJ高、中、低剂量组的治愈率分别为75.0%、80.0%、65.0%,有效率分别为90.0%、95.0%、80.0%。模型组雏鸡血清中IL-10含量降低,IL-6含量升高,与空白组比较,差异显著（P<0.05或P<0.01）;在给药第3、5天时,BQJGHJ高、中、低剂量组、阳性药物组雏鸡血清中IFN-γ（第5天时,高剂量组差异极显著,P<0.01,其他时间、其他组差异均不显著）、IL-10含量（第5天时差异极显著,P<0.01）升高,雏鸡血清中IL-6含量降低,与模型组比较,均差异显著（P<0.05）。在停药后2 d,BQJGHJ高、中、低剂量组、阳性药物组雏鸡血清中IFN-γ、IL-10含量升高,雏鸡血清中IL-6含量降低,与模型组比较,均差异显著（P<0.05或P<0.01）;BQJGHJ高、中、低剂量组雏鸡血清中IFN-γ、IL-6、IL-10含量,与阳性药物组相比,无显著性差异（P>0.05）。BQJGHJ可提高传染性支气管炎雏鸡血清中IFN-r、IL-10的含量,降低传染性支气管炎雏鸡血清中IL-6的含量,发挥治疗鸡传染性支气管炎的作用。     

Development and application of a multiplex polymerase chain reaction for avian respiratory agents

A multiplex polymerase chain reaction (PCR) was developed and optimized to simultaneously detect 6 avian respiratory pathogens. Six sets of specific oligonucleotide primers for infectious bronchitis virus (IBV), avian influenza virus (AIV), infectious laryngotracheitis virus (ILTV), Newcastle disease virus (NDV), Mycoplasma gallisepticum (MG), and Mycoplasma synoviae (MS) were used respectively in the test. With the use of agarose gel electrophoresis for detection of the PCR-amplified DNA products, the sensitivity of detection was between 10 pg for IBV, AIV, MG, and ILTV and 100 pg for NDV and MS after 35 cycles of PCR. Similar sensitivity of these primers was achieved with chickens experimentally infected with respiratory pathogens. In experimental infections, the multiplex PCR was able to detect all the infected chickens in each group at I and 2 wk postinfection as compared with serologic tests at 2 wk postinfection that confirmed the presence of specific antibodies. The multiplex PCR was also able to detect and differentiate coinfections with two or more pathogens. No specific DNA amplification for respiratory avian pathogens was observed among noninoculated birds kept separately as a negative control group.     

Serological monitoring on layer farms with specific pathogen-free chickens

To monitor the existence of avian pathogens in laying chicken flocks, specific pathogen-free (SPF) chickens were introduced into two layer farms and reared with laying hens for 12 months. SPF chickens were bled several times after their introduction and examined for their sero-conversion to avian pathogens. As a result, antibodies to eight or ten kinds of pathogens were detected in SPF chickens on each farm. Antibodies to infectious bronchitis virus (IBV), avian nephritis virus, Mycoplasma gallisepticum and M. synoviae were detected early within the first month. Antibody titer to IBV suggested that the laying chickens were infected with IBV repeatedly during the experiment on both farms. However, antibodies to infectious bursal disease virus and 6 pathogens were not detected.     

Study on Efficacy of Baihu Dingchuan Oral Liquid

In order to verify the effect of Baihu Dingchuan oral liquid of new veterinary drugs,the effects of infectious bronchitis virus (IBV) on the proliferation inhibition test, tracheal cilia movement test and SPF chickens infected with IBV were tested.The test solution was mixed with an equal amount of IBV solution,inoculation of 11-day-old SPF chicken embryo,incubation at 37℃ for 168 h.RT-PCR was performed to detect IBV in kidney of live chick embryo.The results showed that the survival rate of 168 h chicken embryo was 80% in the drug group,but the positive control group was 20%, and there was significant difference between two groups (P<0.05). In the test drug group, no band was detected by RT-PCR, but the target band appeared in the positive control group.After 40 days old SPF chickens were administered continuously for 3 days, 0.02 mL of ink was injected into the trachea. The distance of ink movement in 1 min was measured. The results showed that the migration distance of ink was extremely significantly higher than that of saline control group (P<0.01).In the 17-day-old SPF chickens, IBV-M41 was infused into the nasal mucosa with 0.3 mL. After 24 h, 1 mL/kg was administered for 5 days. The results showed that there were significant differences in clinical symptom score and cure rate between the test drug group and the control group (P<0.05). There was no significant pathological changes in the tracheal mucosa of the experimental group, but the pathological changes in the positive control group were significant. The above results showed that Baihu Dingchuan oral liquid had good inhibitory effect on IBV in vitro, which could promote the movement of tracheal cilia, and had good clinical control effect on infectious bronchitis.     

复方中药对人工感染IBV雏鸡免疫指标的影响

采用滴鼻法对SPF鸡攻毒建立鸡传染性支气管炎感染模型,使用MTT法、流式细胞仪技术、气管环中和试验法等,从细胞免疫和体液免疫角度研究复方中药防治鸡传染性支气管炎的可能性.结果显示,与感染不给药组相比,复方中药组能显著增加病鸡的体质量(P<0.05),促进免疫器官生长发育,提高淋巴细胞转化率和血清中和抗体效价(P<0.05),极显著提高CD4+/CD8+比值(P<0.01).结果表明,复方中药能明显改善传染性支气管炎感染鸡细胞免疫和体液免疫功能低下的状态,具有提高机体抗病毒感染的作用.     

Experimental Escherichia coli respiratory infection in broilers

This study determined optimal conditions for experimental reproduction of colibacillosis by aerosol administration of avian pathogenic Escherichia coli to 2-to-4-wk-old broiler chickens. The basic model for reproducing disease was intranasal administration of approximately 10(4) mean embryo infectious dose of infectious bronchitis virus (IBV) followed by aerosol administration of an 02 or an 078 strain of E. coli in a Horsfall unit (100 ml of a suspension of 10(9) colony-forming units/ml over 40 min). Scores were assigned to groups of infected chickens on the basis of deaths; frequency and severity of lesions in the air sacs, liver and heart; and recovery of the challenge E. coli 6 days post-E. coli infection. An interval of 4 days between the IBV and E. coli challenges was best whether the chickens received the IBV at 8 or 20 days of age. Typically, 50%-80% of the chickens developed airsacculitis and 0 to 29% of the chickens developed pericarditis or perihepatitis, with little or no mortality. Escherichia coli alone resulted in no deaths and 0 to 20% airsacculitis, but these percentages increased to 0 to 5% and 52%-60% when the E. coli aerosol was administered through a cone-shaped chamber. Administration of IBV alone failed to induce lesions. Recovery of the challenge E. coli from chickens did not correlate well with lesions. On the basis of these data, administration of IBV to 20-day-old chickens followed 4 days later by exposure to an avian pathogenic E. coli reproduces avian colibacillosis with the low mortality, high percentage of airsacculitis, and low percentage of septicemic lesions characteristic of the conditions seen in the natural disease.     

中兽药新制剂清瘟败毒颗粒对鸡人工感染支气管炎的防治试验

鸡传染性支气管炎是一种急性高度接触性呼吸道传染病,影响鸡的产蛋量和蛋品质。本研究以鸡传染性支气管炎病毒标准株M41人工感染21日龄700只海兰褐雏鸡,使其发病。接种病毒前后在饮水中分别添加不同剂量的清瘟败毒颗粒,以清瘟败毒散为对照治疗组,观察不同处理鸡的临床症状、发病率、病理变化和死亡率等。结果表明：饮水中添加0．z5％o清瘟败毒颗粒,对IBV标准株M41的攻毒保护作用与阳性对照组相比较差异显著（P〈0．05）;清瘟败毒颗粒低剂量治疗组与高、中剂量治疗组及清瘟败毒散治疗组之间差异显著,因水中添加0．5‰清瘟败毒颗粒,对人工感染鸡传染性支气管炎治疗作用明显,治愈率达88．00％,显著高于清瘟败毒散治疗组（P〈0．05）。     

Serum levels of chicken mannan-binding lectin (MBL) during virus infections; indication that chicken MBL is an acute phase reactant

Mannan-binding lectin (MBL) is a serum collectin which is believed to be an opsonin of the innate immune defence against various microorganisms. MBL is a minor acute phase reactant in man. We investigated the concentration of serum MBL in chickens infected with infectious bronchitis virus (IBV) and infectious laryngotracheitis virus (ILTV). The concentration of serum MBL increased about twofold (from approximately 6 to 12 μg/ml) due to these viral infections. The concentration peaked 3–7 days after infection with IBV, and 3–5 days after ILTV infection, depending on the ILTV strain used. The increased levels returned to normal values 6–10 days after infection. The results indicated that MBL is a minor acute phase reactant in chickens.