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《中国兽医杂志》2019,(1)
为确定使雏鸡获得良好免疫效果的最小巨型艾美耳球虫(E.maxima)早熟株接种量,分别于4日龄对免疫攻毒组以不同剂量进行首免,11日龄以首免2倍剂量对二次免疫攻毒组鸡进行二免。一次或二次免疫后7 d或10 d用同源亲本株进行攻毒,检测免疫攻毒鸡相对增重率、卵囊减少率、病变记分减少率(RLS)和抗球虫指数(ACI)。结果显示,一次免疫剂量≥400个孢子化卵囊/只或两次免疫的一免剂量和二免剂量≥100个孢子化卵囊/只和200个孢子化卵囊/只时,各免疫攻毒鸡的相对增重率≥85%,RLS≥70%,卵囊减少率≥75%,相对保护率≥90%,ACI≥170,均达到良好免疫效果。故将E.maxima早熟株的一次免疫最小免疫剂量定为400个孢子化卵囊/只,两次免疫最小免疫剂量定为一免100个孢子化卵囊/只和二免200个孢子化卵囊/只。 相似文献
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检测鸡球虫四价弱毒疫苗抗体应答的ELISA方法的建立及初步应用 总被引：1，自引：0，他引：1
本研究旨在建立检测鸡球虫四价弱毒疫苗(柔嫩艾美耳球虫、毒害艾美耳球虫、堆型艾美耳球虫、巨型艾美耳球虫)抗体应答的酶联免疫吸附试验(ELISA),并初步阐明鸡免疫四价弱毒疫苗及攻虫后的抗体应答。将300羽岭南黄鸡分为A(免疫攻虫组)、B(不免疫不攻虫组)、C(不免疫攻虫组)共3个组。A组雏鸡在4日龄时进行首免,11日龄时鸡开始二免,二免完成后(17日龄时)对A组及C组的鸡进行攻虫(28万个4种球虫的混合卵囊/羽),7 d后检查A、C两组鸡的存活率。在鸡二免和三免完成后,分别对A、B组进行采血,通过优化最佳抗原包被浓度、酶结合物工作浓度及最佳血清稀释度,建立了ELISA方法来检测鸡体对球虫四价弱毒疫苗的抗体应答情况。A组鸡血清抗体的平均D值为0.870和0.904,明显高于B组鸡的平均D值0.261和0.270,证明了鸡体免疫疫苗后可以刺激产生相应抗体。免疫鸡攻虫后的存活率和抗体应答的检测结果,都充分说明了此鸡球虫弱毒四价疫苗具有良好的免疫原性,所建立的ELISA方法为今后评价鸡球虫弱毒四价疫苗的免疫效力提供了有效手段。 相似文献
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本研究采用早熟选育技术，诱导选育出1株与已获得的山东株免疫原性差异较大的巨型艾美耳球虫(Eimeria maxima)山西株的早熟弱毒株，并对其进行生物学特性研究。结果表明：早熟诱导获得的巨型艾美耳球虫山西早熟株卵囊略小于亲本株，潜隐期为109 h;早熟株各组小肠病变记分差异显著低于(P<0.05)亲本株组，且临床症状较亲本株组弱；等剂量下，早熟株组的卵囊产量及卵囊繁殖力低于亲本株组；早熟株单次免疫剂量≥400个卵囊/只、2次免疫的一免剂量≥100个卵囊/只、二免剂量≥200个卵囊/只时可达到良好免疫效果。本研究结果为制备高效广谱、免疫原性良好的鸡球虫疫苗提供虫株和理论依据。 相似文献
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鸡堆型艾美耳球虫早熟株的最小免疫剂量研究 总被引：1，自引：0，他引：1
《中国兽医学报》2016,(2):244-248
为确定堆型艾美耳球虫(Eimeria acervulina)早熟株的最小免疫剂量,设立了6个早熟株1次免疫组、6个早熟株2次免疫组、2个空白对照组、2个攻毒组。SPF鸡4日龄时以200、300、400、500、600、1 000个/羽的剂量接种早熟株卵囊进行第1次免疫,于14日龄使用1次免疫2倍的剂量进行第2次免疫。一次/二次免疫组及各不免疫攻虫组分别于18或28日龄以2×105个/羽的同源强毒株进行攻毒,以相对增重率、病变记分、病变记分减少率、卵囊抑制率和抗球虫指数(ACI)等指标评价免疫效果,确定最小免疫剂量。结果显示,本次试验使用的早熟株具有良好的免疫原性,不同免疫剂量均能诱发雏鸡产生保护力,且随着免疫剂量的增加保护力逐渐提高。一次免疫剂量为1 000个/羽和二次免疫的首次免疫剂量大于等于400个/羽、第二次免疫800个/羽,可达到良好免疫效果,可分别定为E.acervulina早熟株一次免疫和二次免疫的最小免疫剂量。 相似文献
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毒害艾美耳球虫二次感染对雏鸡局部黏膜组织抗体生成细胞的影响 总被引：1，自引：1，他引：0
180只14日龄雏鸡随机分为毒害艾美球虫(Eimeria necatrix,E. necatrix)一次感染组、二次感染组和对照组。应用免疫酶组织化学染色法,对免疫相关指标进行了检测。结果发现,毒害艾美球虫二次感染雏鸡局部黏膜免疫组织的IgA、IgM、IgG生成细胞数量均不同程度的高于未感染毒害艾美球虫的对照组雏鸡,表明E. necatrix二次感染雏鸡局部黏膜组织的免疫功能明显增强。 相似文献
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肉鹅H5亚型禽流感疫苗免疫效果的研究 总被引：2，自引：0，他引：2
选用H 5亚型禽流感油乳剂灭活疫苗(H 5N 1,R e1株)对马岗鹅作首免日龄、免疫次数与免疫剂量的免疫试验。结果表明,雏鹅在7、14或21日龄作1次免疫均产生免疫应答,其中14与21日龄免疫组免疫后第5周抗体水平均达4 log2以上,抗体动态变化均值与峰值均高于7日龄免疫组2~3个滴度。用0.5、1和2 m l/只3个剂量对14日龄雏鹅的免疫试验中,0.5m l组抗体水平上升过程缓慢,免疫后4周抗体水平才达4 log2以上,1与2 m l组在免疫1周后上升速度较快,免疫后2周即达4 log2以上,抗体水平相近,但2 m l免疫组免疫后5~7周抗体水平均低于1 m l免疫组。说明接种剂量为1或2 m lH 5N 1油苗比接种0.5 m l的免疫效果好,尤以1 m l免疫剂量效果最好。雏鹅在7、14日龄或14、21日龄作2次免疫和7、14、21日龄作3次免疫,首免后抗体上升速度快,各检测点抗体水平均值相近,均在首免后3周达到4 log2以上,4~5周达6 log2以上,4~7周的抗体水平均高于14日龄1次免疫组,且提前2周达到4 log2以上,说明2次、3次免疫组的抗体水平高于1次免疫组,而2次与3次免疫组的抗体水平无明显差异。以上结果说明,在肉鹅生产的禽流感免疫中,选择以14日龄首免0.5 m l/只,21日龄2免接种1 m l/只可取得较为理想的免疫效果。 相似文献
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将90只14日龄雏鸡随机分为3组,即毒害艾美耳球虫二次感染组(Ⅰ组)、一次感染组(Ⅱ组)和对照组(C组),通过对空肠和盲肠肠液中超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性及丙二醛(MDA)含量动态变化的测定,探究毒害艾美耳球虫感染对雏鸡空肠和盲肠肠液氧化、抗氧化能力的影响。结果表明,初次小剂量感染毒害艾美耳球虫后,雏鸡空肠和盲肠液中SOD和CAT活性及MDA含量明显升高;大剂量攻击性感染毒害艾美耳球虫后,Ⅰ组雏鸡肠液中SOD和CAT活性明显高于Ⅱ组雏鸡,但明显低于C组雏鸡。同时,Ⅰ组和Ⅱ组雏鸡肠液中MDA含量均高于C组雏鸡,且Ⅱ组雏鸡又明显高于Ⅰ组雏鸡。由此可见,毒害艾美耳球虫对雏鸡空肠和盲肠肠液氧化-抗氧化平衡的影响与其感染剂量和次数密切相关,为进一步探讨鸡球虫的致病机制提供了重要的参考依据。 相似文献
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将180只14日龄雏鸡随机分为毒害艾美球虫（Eimeria necatrix）初次感染组、二次感染组和对照组，应用免疫SPA菌体花环、间接ELISA及细胞培养技术和四甲基偶氮唑盐（MTT）测定法对相关免疫学指标进行了检测，以研究毒害艾美球虫二次感染对雏鸡外周血液免疫功能变化的影响。结果显示，毒害艾美球虫二次感染雏鸡外周血液T、B淋巴细胞数量及其对ConA或PMA的增殖反应和血清IgG、IgM、IgA免疫球蛋白含量均不同程度地高于未感染毒害艾美球虫的对照组雏鸡。证实毒害艾美球虫二次感染雏鸡外周血液的细胞免疫和体液免疫功能均明显提高。 相似文献
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给18日龄鸡胚接种一定剂量的柔嫩艾美耳球虫(Eim eria tenella)和/或堆形艾美耳球虫(E.acervulina)孢子化卵囊,出雏后在无球虫环境中笼养,1~10日龄每天收集各组粪便样本,计数克粪便卵囊数(OPG),并于14日龄时以大剂量同源孢子化卵囊攻虫,以相对增重率(RWG)、饲料转化率(FCR)、相对卵囊产量(ROP)评价免疫保护效果。结果显示,以E.tenella或E.acervulina卵囊免疫18日龄鸡胚,其卵囊排出的潜隐期及达到峰值的时间与1日龄雏鸡接种组相一致,有相似的排卵囊曲线,提示其诱导免疫的建立是在出雏后开始建立的。攻虫后各免疫组的RWG由攻虫对照组的31.9%~51.7%提高到了76.5%~83.6%,RCR由攻虫对照组的4.11~4.89改善为2.72~2.96,ROP降至4.7%~23.5%。结果表明以一定剂量E.tenella和E.acervulina卵囊单独或混合经羊膜腔免疫18日龄鸡胚都可以建立起针对出雏后14日龄同源攻虫的良好免疫保护力。比较混合免疫E.tenella和E.acervulina卵囊组与单一接种E.tenella或E.acervulina卵囊组的免疫效果发现,混合免疫组的各项指标均稍优于后者。 相似文献
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Immune responses in chickens to Eimeria tenella using oral and subcutaneous routes of infection were investigated. The results obtained indicated that sporulated oocysts inoculated subcutaneously in doses up to 50 000 oocysts per bird were not fatal to 21-day-old chicks. Subcutaneous inoculation of oocysts was found to be less immunogenic than oral administration. The dynamics of the antibody responses were different for the two routes of infection. Orally administered oocysts stimulated a dramatic primary increase in the serum antibody titre with a tendency towards a decrease in the titre 14 days post infection irrespective of second infections at that time. However, a third oral dose of oocysts stimulated a slight increase in antibody titre. Two doses of oocysts injected subcutaneously induced only a slight increase in serum antibody titre. Such a low titre was dramatically increased following a subsequent oral dose of oocysts. Antibodies specific to E. tenella are IgM and IgG immunoglobulins. IgA immunoglobulin was not investigated. 相似文献
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An experiment was carried out to assess the influence of tannic acid (TA) on integrity of the intestine in broiler chicks vaccinated against coccidiosis and challenged with the disease. In a 2 × 2 factorial design, the trial had five groups of 10 chickens each, including positive (group 2) and negative (group 1) controls. The chickens were kept on wood shavings and fed a commercial maize and soybean-based starter-grower diet. From day 1, groups 3 and 5 received TA (10 g kg(-1)) in their diet. On day 4, birds of groups 4 and 5 were vaccinated orally against coccidiosis with anti-coccidial vaccine, Livacox T?. Each dose of the vaccine contained 300-500 sporulated oocysts of each of Eimeria acervulina, Eimeria maxima and Eimeria tenella. On day 18, all experimental groups except for the negative (group 1) were challenged with 10-fold dose of Livacox T? to produce a mild coccidiosis infection. Faecal samples of individual birds were collected on day 23, and the number of faecal oocysts was determined. d-Xylose absorption test was also carried out on all birds on day 23. Immediately after d-xylose absorption test, all birds were killed humanely and the intestinal tract was removed, weighed and examined for gross lesions. Results showed that negative (group 1) and positive controls (group 2) had the highest and lowest levels of plasma d-xylose post-ingestion of the substrate, respectively. Vaccination and/or feeding TA raised the level of plasma d-xylose in infected birds, although this was not significant for TA-fed birds. Vaccination reduced but TA increased the total number of oocysts per gram of faeces. Birds of groups 2-5 had distinct intestinal lesions when compared with group 1. However, vaccination prevented intestinal lesions. Relative weights of intestinal parts were the lowest in group 1 and the highest in group 2. Vaccination but not TA reduced the relative weights of intestinal parts in infected birds. It was concluded that dietary tannins may reduce the efficacy of anticoccidial vaccines and alter the proper development of immunity against the disease. 相似文献
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采用单卵囊感染技术,从鸡球虫混合种中分离出一株堆型艾美尔球虫(Eimeria acenrulina).并对该株堆型艾美尔球虫的病理学做了进一步研究.利用堆型艾关尔球虫的寄生部位、肉眼病变、最小潜在期等生物学特性进行鉴定,并做回归试验,用此球虫卵囊1×105个感染雏鸡.取感染5d后有明显病理变化的十二指肠组织,采用石蜡切片技术,进行病理学观察.结果表明,虫体寄生于肠绒毛上皮细胞内,大量的肠绒毛遭到破坏、断裂和脱落. 相似文献
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Ibuprofen (IBU)-a nonsteroidal anti-inflammatory drug-inhibits the biosynthesis of prostaglandins with pro-inflammatory and immunosuppressive properties and is therefore proposed as a candidate molecule for the treatment of coccidiosis in broiler chickens. In all experiments, IBU was administered via drinking water. In a first experiment, chickens were infected at 10 or 21 days of age with oocysts of Eimeria acervulina (5 X 10(4)), Eimeria maxima (3 X 10(4)), and Eimeria tenella (7.5 X 10(3)) and medicated with IBU at a dose of 15 mg/kg body weight (BW). In a second experiment, chickens were infected at 6 days of age with 10(4) oocysts of E. acervulina and medicated with IBU at a dose of 100 mg/kg BW. In the third experiment, an inoculum consisting of 5 x 10(4) or 10(5) E. acervulina oocysts was administered at 6 days of age to chickens medicated with IBU at a dose of 100 mg/kg BW. In a fourth experiment, the effect of IBU on sporulation and infectivity of E. acervulina oocysts was studied. Coccidial lesion scores (CLSs), oocyst shedding, and weight gain were used as evaluation parameters in all experiments except the fourth, where weight gain was not taken into account. In addition, the sporulation percentage was determined in the last experiment. No influence of IBU on the indicated parameters was observed after providing the drug at a dose of 15 mg/kg BW, whereas CLSs and oocyst shedding were reduced when IBU was provided at a dose of 100 mg/kg BW. However, IBU did not significantly show any effect on the degree of sporulation and infectivity of E. acervulina oocysts at a dose of 100 mg/kg BW. 相似文献
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Eimeria parasites were isolated from Nanhai Guangdong province (southern China) and studied in chickens in wire cages to evaluate their drug resistance against commonly used ionophores: monensin (100 mg/kg of feed), lasolacid (90 mg/kg), salinomycin (60 mg/kg), maduramicin (5 mg/kg) and semduramicin (25 mg/kg). Chinese Yellow Broiler Chickens were infected with 40,000 crude sporulated Eimeria oocysts at 15 days of age and prophylactic medication commenced a day prior to infection. Drug resistance was assessed for each ionophore drug by calculating the anticoccidial index (ACI) and percentage optimum anticoccidial activity (POAA) based on relative weight gain, rate of oocyst production and lesion values. Results revealed that Nanhai Eimeria oocysts comprising of E. tenella, E. maxima and E. acervulina, were resistant to monensin, sensitive to both salinomycin and lasolacid and partially sensitive to maduramicin and semduramicin. By selection for early development of oocysts during passage through chickens, the prepatent time of E. tenella, E. maxima and E. acervulina were reduced by 49, 36 and 22 h, respectively. The precocious lines are less pathogenic than the parent strains from which they were selected and conferred a satisfactory protection for chickens against coccidiosis. These ionophore-tolerant precocious lines could have wider applications in the development of anticoccidial vaccines for sustainable control of coccidiosis. 相似文献
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Precocious lines of Eimeria acervulina "Cu" and "I" strains were obtained after 25 passages of oocysts in chickens that showed a shortening of the prepatent period for first oocyst output from 96 h to 81 and 82 h, respectively. Both precocious lines were evaluated for pathogenicity using as criteria weight gain, lesion score and total oocyst production. Infection of the "Cu" precocious line in chickens showed a high weight gain, low lesion score and low oocyst production, when compared to parent strain infected chickens. However, the results did not show a significant difference in relation to the criteria used above for the E. acervulina "I" precocious line when compared to its parent strain. This suggests a low degree of attenuation for the "I" strain but good attenuation for the precocious "Cu" line. The histopathological observations of chickens infected with the E. acervulina "Cu" parent strain and precocious line, comparing life cycle and intestinal lesions, showed: (1) parasite stages only in the border cells of infected chicken intestinal villi, for the precocious line; (2) parasite stages in the border cells of the intestinal villi and submucosa cells near the Lieberkühn glands of the intestine; and (3) high degree of inflammatory cells around the parasites in chickens infected with the parent strain. The "Cu" strain was also characterized for sensitivity against eight anticoccidial drugs. Sensitivity was observed for four anticoccidial drugs and partial resistance for four other drugs, although the strain had never had previous contact with anticoccidial drugs, suggesting the presence of a natural resistance factor. This Brazilian E. acervulina "Cu" precocious line showed attenuation for pathogenicity in chickens, suggesting that it could be a suitable strain for use as a live vaccine in Brazil. 相似文献
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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。 相似文献
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为了选育堆形艾美耳球虫（Eimeria acervulina）早熟株及观测其生物学特性,运用Jeffers创立的艾美耳属球虫早熟株选育方法,对实验室保存的堆形艾美耳球虫进行连续传代早熟选育,并对获得的早熟株与母株孢子化卵囊大小、繁殖能力、致病性以及免疫保护力等指标进行了测定,比较堆形艾美耳球虫早熟株与母株之间的基本生物学特性差异。经过18代早熟选育后,堆形艾美耳球虫的潜在期由母株的99h缩短至84h。与母株相比,早熟株的孢子化卵囊大小明显减小（P〈0．05）,卵囊繁殖能力降低了17％～42%。致病性试验中,早熟株感染组的平均增重均高于母株,而病变记分相当。免疫保护试验中,早熟株与母株的免疫保护力相当,其卵囊抑制率略低于母株,差异不明显（P〉0．05）。结果表明,本研究成功选育出堆形艾关耳球虫早熟株,对母株攻击具有保护力,为鸡球虫疫苗的研制奠定了基础。 相似文献