Zaheer Iqra, Chen Wei, Khan Ahrar, Elokil Abdelmotaleb, Saleemi Muhammad Kashif, Zaheer Tean, Khan Muhammad Zargham
Department of Pathology, University of Agriculture, Faisalabad, Pakistan.
Institute of Animal Science, Guangdong Academy of Agricultural Sciences, Animal Nutrition and Feed Science in South China, Ministry of Agriculture and Rural Affairs, State Key Laboratory of Livestock and Poultry Breeding, Key Laboratory of Guangdong Public Laboratory of Animal Breeding and Nutrition, Guangdong Key Laboratory of Animal Breeding and Nutrition, Guangzhou, China.
Front Vet Sci. 2022 Jul 26;9:947522. doi: 10.3389/fvets.2022.947522. eCollection 2022.
This study was designed to compare immunopathological effects of vaccination with post-hatch vaccination against IBD in White Leghorn chicks. A total of 189 embryonated eggs were divided into six groups. At day 18 of incubation, groups A-C were administered with 228E, Winterfield 2512:10/3 and 2512/90:10/2.7, respectively, group D (post-hatch vaccination) and group E as shamed control (for quality evaluation of vaccination technique), and group F as control. The results showed that antibody titers against IBD detected by ELISA on days 2, 17, and 28 were significantly higher in all groups as compared to control groups E and F. On day 17, all vaccinated groups ( and post-hatch vaccinated) showed no significant differences in antibody titers among themselves; however, at day 28, only the post-hatch group showed significantly higher antibody titers followed by vaccinated groups. The cell-mediated immunity determined by PHA-P assay was significantly higher in all vaccinated groups than the non-vaccinated groups. No clinical signs of IBD infection were observed in any of the vaccinated groups. There was only increase in bursa size of groups vaccinated with intermediate plus strains (groups A, C, and D) at day 28. The histopathology showed that all the treatment groups had mild lesions induced by IBD virus in bursa. This study concluded that vaccination with live IBD vaccines provides protective immunity to the chickens even in the presence of IBD-specific MDA; therefore, the onset of immunity was much earlier than the post-hatch vaccination and groups also maintained protective immunity against IBD for longer time.
本研究旨在比较孵化后接种传染性法氏囊病（IBD）疫苗对白来航雏鸡的免疫病理影响。总共189枚受精蛋被分为六组。在孵化第18天，A - C组分别接种228E、温特菲尔德2512:10/3和2512/90:10/2.7，D组（孵化后接种疫苗）和E组作为假对照（用于评估接种技术质量），F组作为对照。结果显示，与E组和F对照组相比，在第2、17和28天通过ELISA检测的针对IBD的抗体滴度在所有组中均显著更高。在第17天，所有接种疫苗组（包括孵化后接种组）之间的抗体滴度无显著差异；然而，在第28天，只有孵化后接种组的抗体滴度显著更高，其次是接种疫苗组。通过PHA - P试验测定的细胞介导免疫在所有接种疫苗组中显著高于未接种疫苗组。在任何接种疫苗组中均未观察到IBD感染的临床症状。仅在第28天，接种中等偏强毒株的组（A、C和D组）的法氏囊大小有所增加。组织病理学显示，所有治疗组的法氏囊中均有由IBD病毒诱导的轻度病变。本研究得出结论，即使存在IBD特异性母源抗体，接种IBD活疫苗也能为鸡提供保护性免疫；因此，免疫开始时间比孵化后接种疫苗早得多，且这些组对IBD的保护性免疫也能维持更长时间。
