免疫增强剂对鸡球虫免疫保护力的作用

选取免疫增强剂卡介苗（BCG）与黄芪多糖（APS）以比较不同用法、不同攻虫强度下其增强鸡球虫免疫保护力的效果。结果表明：BCG和APS均具有明显的免疫促进作用，能更有效地抵抗5万和25万E.Tenella卵囊的攻击，但BCG效果优于APS；BCG和APS大剂量或重复使用效果均不理想；BCG的最佳使用方法为：以0.025ml／只的剂量于球虫免疫前7d使用1次。     

GC02鸡球虫病疫苗免疫效果的观察

试验研究了GC02鸡球虫病疫苗免疫预防鸡球虫病的效果.试验一选择100只肉杂鸡,饲养至21日龄时,随机分为A、B、C、D四组,其中A组免疫肉鸡球虫病疫苗,B组免疫GC02鸡球虫病疫苗,C组为不免疫攻虫组,D组为不免疫不攻虫组,A、B组于21日龄口服免疫球虫苗,A、B、C三组于28日龄时口服接种1×105个孢子化卵囊攻虫,于36日龄捕杀A、B、C、D组全部鸡只,以比较肉鸡球虫病疫苗与GC02鸡球虫病疫苗的预防效果.结果表明两种球虫病疫苗均能有效的抗雏鸡艾美耳球虫感染,且是安全有效的.试验二选择100只肉杂鸡,随机分为Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ五组.研究了GC02鸡球虫病疫苗不同免疫次数的保护作用,Ⅰ组于14日龄免疫GC02鸡球虫病疫苗(4 000个卵囊),Ⅱ组分别于7日龄(4 000个卵囊)、21日龄(8 000个卵囊)免疫GC02鸡球虫病疫苗,Ⅲ组分别于7日龄(4 000个卵囊)、14日龄(8 000个卵囊)、21日龄(12 000个卵囊)免疫GC02鸡球虫病疫苗,Ⅳ组为不免疫攻虫组,Ⅴ组为不免疫不攻虫组,于28日龄时,Ⅰ、Ⅱ、Ⅲ、Ⅳ组均口服接种1×105个孢子化卵囊攻虫,36日龄捕杀全部鸡只,观察GC02鸡球虫病疫苗不同免疫次数的免疫效果.结果表明2次免疫的效果优于1次免疫和3次免疫,2次免疫能有效的控制球虫病的发生,对雏鸡有明显的促生长作用.     

rChIFN-γ对E-tenella卵囊免疫雏鸡肠道分泌型IgA^＋细胞数量的影响

本研究初步探讨了重组鸡-γ干扰素（rChIFN-γ）对柔嫩艾美耳球虫（E．tenella）卵囊免疫接种鸡肠道粘膜sIgA＋细胞数量的影响。分另1l给7和14日龄雏鸡予以E．tenella孢子化卵囊免疫接种并同时肌注5000urChIFN-γ后,于21日龄用同源E．tenella攻虫。免疫组化检测结果表明rChIFN-γ加强免疫组在21日龄时十二指肠、空肠、盲肠和回肠的绒毛sIgA^＋细胞数量均高于免疫对照组,在28日龄时,均呈现显著性差异（仪=0．05）。结果表明rChIFN-γ可提高球虫卵囊免疫雏鸡肠道内的sIgA^＋细胞数量,增强粘膜免疫水平,具有明显的抗球虫免疫增强效果。     

免疫增强剂促进鸡球细胞免疫的研究

艾维茵雏鸡分别于７日龄和１４日龄时以１０００、５０００个Ｅ．Ｔｅｎｅｌｌａ卵囊／只免疫２次,并于首免时注射卡介苗（ＢＣＧ）或黄芪多糖（ＡＰＳ）１次,２１日龄以５万和２５万卵囊攻击。试验鸡采血时间为７、１４、２１和２８日龄。细胞免疫测定指标为淋巴细胞转化水平、Ｅ－玫瑰花环形成率、血清溶菌酶含量。结果表明：ＢＣＧ和ＡＰＳ能显著提高球虫免疫鸡的淋巴细胞转化水平和Ｅ－玫瑰花环形成率：是鸡体单核－巨噬细胞系统的有效激活剂。     

柔嫩艾美耳球虫卵囊免疫后鸡盲肠扁桃体GM-CSF基因表达的动态变化

为检测和评价鸡粒细胞巨噬细胞集落刺激因子（ChGM-CSF）在抗球虫免疫过程中的作用,以RT-PCR技术从鸡盲肠扁桃体中克隆获得了ChGM-CSF编码基因的开放阅读框（ORF）,其长为435 bp。将试验鸡随机分为对照组和试验组,试验组于12、22日龄时用E. tenella孢子化卵囊进行免疫,分别于设定时间每次取5只鸡采集盲肠扁桃体,以鸡β-actin为参照建立半定量RT-PCR方法检测ChGM-CSF的表达动态。结果表明,在第1次免疫后的第1天（13日龄,P＜0.05）和第2次免疫后的第7天（29日龄,P＜0.01）,试验组ChGM-CSF的表达量显著高于对照组;在第1次免疫后的第9天（21日龄）和第2次免疫后的第3天（25日龄）ChGM-CSF的表达量显著低于对照组（P＜0.01）。本研究提示ChGM-CSF参与了鸡体的抗球虫感染过程,为进一步探讨ChGM-CSF的生物学活性及作为鸡球虫病基因工程疫苗佐剂的研究奠定基础。     

NO对接种Eimeria acervulina雏鸡体液免疫水平的影响

用1日龄黄羽肉鸡研究了一氧化氮(NO)对接种Eimeria acervulina雏鸡体液免疫水平的影响.试验设3个对照组(免疫对照组、感染对照组、空白对照组)和3个试验组(L-精氮酸组、L-氨基胍组、NG亚硝基-L-精氦酸甲基酯组),每组8只鸡.免疫程序为,7日龄时初免,接种卵囊3×103个/只;14日龄时二免,接种卵囊5×103个/只;21日龄时三免,接种卵囊1×104个/只;28日龄时四免,接种卵囊3×106个/只.感染对照组用于判断本试验所采用的免疫程序是否成功,该组鸡仅在28日龄时感染卵囊1次,剂量为3×106个/只.3个对照组从7日龄开始直至扑杀当日连续口服生理盐水0.5 mL/次,2次/d;3个试验组从7日龄开始直至扑杀当日分别口服5 g/L L-精氨酸溶液或3 g/L L-氨基胍溶液或6 g/L NG-亚硝基-L-精氨酸甲基酯溶液,0.5 mL/次,2次/d.38日龄时扑杀全部试验鸡,取血清样本用ELISA法测定抗体水平;取十二指肠样本进行肠道病变记分.试验结果表明,给免疫E.acervulina的雏鸡每日口服NO生成底物L-精氨酸、可增加其血清抗体水平(P<0.05);而口服诱导型NO合成酶(iNOS)抑制剂氨基胍和原生型NO合成酶(cNOS)抑制剂NG-亚硝基-L-精氨酸甲基酯,可明显降低其血清抗体水平(P<0.01).上述结果表明,NO具有提高E.acervulina免疫雏鸡体液免疫水平的作用,且由2种NO合成酶(NOS)催化生成的NO均参与了此过程.     

重组鸡γ干扰素对E.tenella卵囊免疫后肠上皮组织结构的影响

取AA肉鸡，在其7日龄和14日龄时分别给予柔嫩艾美耳球虫（E．tenella）孢子化卵囊进行首免和二免，并同时肌肉注射5000U重组鸡γ干扰素（rChIFN-γ）后，于21日龄以同源E．tenella攻虫。试验结果表明，rChIFN-γ协同球虫活卵囊免疫可减少由于球虫病造成的体质量下降，降低OPG值和肠道病变记分，提高抗球虫指数（ACI）；同时还发现，rChIFN-γ能够显著增加肠道绒毛高度、肠隐窝深度、刷状缘厚度（α=0．05）。由此表明，rChIFN-γ可以减轻由于球虫感染所造成的肠道黏膜损伤，促进肠道的吸收功能，进而减轻球虫病所造成的增重损失，对球虫活卵囊疫苗的免疫有一定的免疫增强效果。     

rChlFN-γ对E.tenella卵囊免疫雏鸡肠道分泌型IgA+细胞数量的影响

本研究初步探讨了重组鸡γ干扰素(rChIFN-γ)对柔嫩艾美耳球虫(E.tenella)卵囊免疫接种鸡肠道粘膜slgA+细胞数量的影响.分别给7和14日龄雏鸡予以E.tenella孢子化卵囊免疫接种并同时肌注5 000 urChlFN-γ后,于21日龄用同源E.tcnella攻虫.免疫组化检测结果表明rChIFN-γ加强免疫组在21日龄时十二指肠、空肠、盲肠和回肠的绒毛sIgA+细胞数量均高于免疫对照组,在28日龄时,均呈现显著性差异(α=0.05).结果表明rChIFN-γ可提高球虫卵囊免疫雏鸡肠道内的sIgA+细胞数量,增强粘膜免疫水平,具有明显的抗球虫免疫增强效果.     

不同剂量和免疫次数对鸡毒害艾美耳球虫免疫保护力的影响

以相对增重率(RBWG)、饲料转化率(FCR)和盲肠相对卵囊产量(ROP)为指标,评价了1次或2次分别以1×103个或3×103个毒害艾美耳球虫(E.necatrix)孢子化卵囊(SO)/鸡剂量免疫接种后特异性免疫力的产生和持续时间。笼养岭南黄肉雏鸡于3日龄1次或3日龄和10日龄2次分别接种不同剂量的E.necatrix SO后,于17日龄(2次免疫组为24日龄)、34日龄和50日龄时以14×104SO/鸡剂量的同源卵囊攻虫,结果表明,免疫后2周卵囊接种鸡已产生坚强免疫力,1次免疫接种者(17日龄)高、低2个不同剂量组的RBWG、FCR和ROP分别为95.5%、2.32、24.54%和101.4%、2.32、21.1%;而2次免疫组(24日龄)的上述指标则分别为106.5%、2.44、9.3%和98.2%、2.38、7.48%。至34日龄和50日龄攻虫时,这些指标均有不同程度的下降,且随着时间延长,下降更为明显,但2次免疫处理组的这些指标均明显优于1次免疫者;同一次处理的不同剂量组间无明显差异。结果揭示,雏鸡口服免疫接种一定剂量的E.necatrix孢子化卵囊后可迅速诱导鸡体特异性免疫力的产生,但免疫保护力在笼养条件下持续时间较短。     

中药复方多糖对鸡红细胞免疫功能的影响

观察不同浓度的中药复方多糖、黄芪多糖（APS）、当归多糖（ASP）及淫羊藿多糖（EPS）对正常罗曼雏鸡免疫功能的影响。将260羽1日龄健康罗曼雏鸡随机分为13组，每组20羽。分别于1日龄皮下注射生理盐水以及中药复方多糖、APS、ASP、EPS，连续注射7d，于7、14、21、28、35、42、49、56日龄采血，检测红细胞免疫功能。试验结果表明：使用中药复方多糖、APS、ASP、EPS后，各试验组红细胞-Gb花环率和红细胞-IC花环率明显升高。中药复方多糖红细胞-C3b花环率和红细胞-IC花环率显著高于其他多糖组。中药复方多糖、APS、ASP、EPS均可提高鸡的红细胞免疫功能，其中以中药复方多糖效果最好。     

柔嫩艾美耳球虫早熟株免疫剂量研究

为了确定柔嫩艾美耳球虫（Eimenatenella）早熟株合适的免疫剂量,本文设立7个早熟株免疫攻虫组、1个不免疫攻虫组和1个不免疫不攻虫组,免疫组的免疫剂量为孢子化卵囊100、200、400、600、800、1000和2000个／羽,经嗉囊感染,7日龄首次免疫,14日龄以同等剂量进行第二次免疫,21日龄以8×10^4个／羽的同源母株进行攻虫,28日龄结束试验,以存活率、增重、肠道病变记分、血便数量、卵囊减少率为观测指标。对免疫保护效果较好的3个免疫剂量进行重复试验,同时设置商品化球虫疫苗对照组,免疫方法、试验周期、试验指标同第一批试验。结果显示：攻虫后,不免疫攻虫组出现5％死亡,而各免疫组来出现死亡;各免疫组卵囊减少率在61．57％～69．52％;200～2000免疫组的增重与不免疫不攻虫组差异不具备显著统计学意义（P〉0．05）;600～2000免疫组的肠道病变记分和血便数量均明显少于不免疫攻虫组（P〈0．05）。用600、800和1000进行重复试验,三个免疫组攻虫期间均来出现死亡,而不免疫组和疫苗对照组均出现5％死亡;三个免疫组的增重均明显高于不免疫攻虫组和疫苗对照组（P〈0．05）;早熟株免疫组的肠道病变记分和血便数量明显低于不免疫攻虫组（P〈0．05）,而疫苗对照组与不免疫攻虫组的相当（P〉0．05）;卵囊减少率在66.30％-78．75％,高于疫苗对照组的51．82％。结果表明,该柔嫩艾美耳球虫早熟株保持了良好的免疫原性,不同免疫剂量均能诱发鸡产生免疫保护力,其中600、800和1000个／羽的免疫效果均优于疫苗对照组,可考虑以600个／羽作为该早熟株在疫苗制备中的推荐免疫剂量。     

Development of protective immunity against Eimeria tenella and E. acervulina in White Leghorn chickens inoculated repeatedly with high doses of turkey coccidia

Repeated inoculation (immunization) of 2-week-old white leghorn chickens with 10(6) oocysts of the turkey coccidia Eimeria adenoeides or E. meleagrimitis partially protected chickens against moderate challenge with E. tenella or E. acervulina oocysts, but not with E. necatrix oocysts. After challenge, mean weight gains of the immunized chickens and the unchallenged controls did not differ significantly, but weight gains of unimmunized chickens were significantly lower. The mean feed-conversion ratio of the immunized challenged chickens was 3.14, as compared with 4.42 for unimmunized challenged control chickens. In general, immunization did not markedly reduce intestinal lesions. Repeated inoculation of chickens with the turkey coccidium E. gallopavonis failed to produce statistically significant protection against challenge with E. tenella, E. acervulina, or E. necatrix, as determined by weight gain, feed-conversion efficiency, and lesion scores. Antibody profiles of individual chickens did not correlate with protection.     

Effect of broiler chicken age on susceptibility to experimentally induced Cryptosporidium baileyi infection

Clinical signs of respiratory tract disease were observed in chickens that were inoculated intratracheally with 1 x 10(6) oocysts of Cryptosporidium baileyi at 2 or 14 days of age (10 chickens/group), but not in chickens inoculated at 28 or 42 days of age (10 chickens/group). Orally inoculated chickens in all age groups (10 chickens/group) did not develop clinical signs of disease. Orally and intratracheally inoculated chickens in all age groups were infected, as determined by the finding of cryptosporidia in tissue sections of the trachea, bursa of Fabricius, and cloaca, and by the recovery of oocysts from their feces. Chickens inoculated at 2 and 14 days of age excreted oocysts for a longer period and had greater numbers of cryptosporidia in their tissues, compared with chickens inoculated at 28 and 42 days of age.     

鸡球虫苗(DLV)免疫引起宿主体液免疫应答和血液生理变化的动态研究

本文对鸡球虫苗（DLV）免疫和免疫后攻击引起鸡体类特异抗体应答和血液重要生理指标的动态变化进行了系统研究。结果发现，DLV每次免疫都激发了高于上次水平的IgG反应，到末次免疫后1～2周鸡体内已达较高IgG水平；IgM仅在初次免疫后第9天检到低水平反应。虫苗免疫对鸡血细胞压积（PCV）、血红蛋白（Hb）含量无任何影响，血脂、血清蛋白量和碱性磷酸酶（SAP）活力在后期有不同程度下降，但很快基本恢复。末次免疫后2周大剂量攻击，攻后6天免疫鸡抗体水平未见升高，且上述各血液指标均无明显变化；而不免疫对照鸡攻击后各血液指标均剧烈下降。     

Avian eimeria: invasion in foreign host birds and generation of partial immunity against coccidiosis

Four species of avian Eimeria invaded the intestine of foreign host birds in the same areas in which they invaded the natural host. Repeated inoculation (immunization) of chickens with the turkey coccidian, Eimeria adenoeides, partially protected the chickens against a subsequent challenge with 5.8 x 10(4) E. tenella oocysts. At 6 days post-challenge, the weight gain and feed conversion efficiency of the immunized chickens was significantly better than those of the chickens that were not immunized with E. adenoeides. Lesion scores and cellular invasion by the sporozoites were significantly lower in the immunized birds than in the unimmunized group. Electrophoresis and Western blot analysis identified changes in the serum antibody profiles of the chickens that appeared to be associated with the immunization and challenge programs. An antibody or antibodies recognizing a 60,000-molecular-weight antigen of E. tenella sporozoites disappeared when chickens immunized with E. adenoeides were challenged with E. tenella; an antibody or antibodies recognizing a 23,000-molecular-weight sporozoite antigen appeared within 6 days of challenge. Reciprocal studies, in which turkeys were immunized with E. tenella and challenged with E. adenoeides, showed little evidence of protection.     

ELISA检测DLV虫苗免疫鸡抗体消长规律的研究

将柔嫩、毒害、巨型艾美耳球虫的孢子化卵囊制成可溶性抗原，用酶联免疫吸附试验检测鸡球虫双重致弱多凤苗虫苗、为柔嫩、毒害、巨型艾美耳球虫三价苗免疫鸡血清抗球虫抗体的消长规律。     

Performance and oocyst shedding in broiler chickens orally infected with Cryptosporidium baileyi and Cryptosporidium meleagridis

To study effects of experimental cryptosporidiosis, broiler chickens were infected per os with 5 x 10(5) oocysts of Cryptosporidium baileyi and Cryptosporidium meleagridis. In the first experiment, chickens were infected with oocysts of C. baileyi at the age of 7, 14, and 21 days. In the second experiment, chickens were infected with oocysts of C. baileyi, C. meleagridis, or both cryptosporidial species at the age of 7 days. Although clinical signs of infection were apparent, neither final live weight nor mortality was significanty influenced in chickens infected with a single Cryptosporidium species. In chickens infected with C. meleagridis, the growth retardation was observed in the 2-wk period after infection. The compensatory growth, however, started when the oocyst shedding had ceased. The number of oocysts in excreta specimens of chickens infected with C. meleagridis was two to three times lower than in excreta of chickens infected with C. baileyi. Chickens infected with both C. baileyi and C. meleagridis (5 x 10(5) oocysts of each) had significantly lower final live weight and worse feed efficiency than chickens of other groups. Concurrent infection did not influence individual C. baileyi or C. meleagridis oocyst shedding.     

Immunization of young chickens by trickle infection with Eimeria tenella.

Immunization of chickens was attempted with low levels of Eimeria tenella oocysts (50 oocysts per day) over the first 1 or 2 weeks of life--the "trickle infection" (TI) method. When chickens were immunized by TI at 0-13 days of age, no cecal lesions and a reduced number of oocysts in ceca were observed after challenge at 17 days of age. TI at 0-6 days of age conferred better protection against challenge with E. tenella than did TI at 7-13 days. However, cecal lesions were observed in almost all of these chickens. These findings indicated that TI for 2 weeks (0-13 days of age) provided better immunity than TI for 1 week (0-6 or 7-13 days of age).     

Protective effects of sugar cane extracts (SCE) on Eimeria tenella infection in chickens

The effects of oral administration of sugar cane extracts (SCE) on Eimeria tenella oocysts infection in chickens were studied with 2 different experiments. In Experiment 1, 3-week-old inbred chickens (MHC; H.B15) were inoculated into the crop with SCE (500 mg/kg/day) for 1 day or 3 consecutive days, and then challenged with E. tenella sporulated oocysts (2 x 10(4) cells/chicken). In Experiment 2, 1-week-old chickens were orally administered SCE at the same dose for 3 consecutive days, and then initially infected with E. tenella sporulated oocysts (2 x 10(3) cells/chicken). At 2 and 3 weeks of age, these chickens were immunized intravenously with the mixed antigens of sheep red blood cells (SRBC) and Brucella abortus (BA). At 4 weeks of age, chickens were challenged with E. tenella sporulated oocysts (1 x 10(5)/chicken). Challenged chickens with E. tenella oocysts showed markedly decreased body weight gain/day, severe hemorrhage and great number of shedding oocysts in feces and high lesion scores. Oral administration of SCE and initial infection with oocysts (2 x 10 (3)/chicken) resulted in a remarkable improvement in body weight gain/day, hemorrhage, the number of shedding oocysts and lesion score, compare to other infected groups. In addition, SCE-inoculated chickens with the initial infection showed a significant increase in antibody responses against SRBC and BA and also improvement in decreased relative proportions of Bu-1a(+) and CD4( )cells in cecal tonsil lymphocytes of E. tenella-challenged chickens. Cecal tissues of chickens administered SCE and initially infected with E. tenella oocysts showed lower numbers of schizonts, gametocytes and oocysts than those of infected control chickens. These results suggest that SCE have immunostimulating and protective effects against E. tenella infection in chickens.