Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, B9820 Merelbeke, Belgium.
Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, B9820 Merelbeke, Belgium.
Poult Sci. 2020 Apr;99(4):2157-2161. doi: 10.1016/j.psj.2019.11.054. Epub 2020 Feb 14.
Oral administration of antibodies is a promising strategy against various infectious diseases. Previously, it was demonstrated that passive immunization by providing hyperimmune egg yolk through the feed reduces Campylobacter jejuni colonization in broilers. Campylobacteriosis is the most commonly reported bacterial foodborne zoonosis worldwide, and poultry products are the number one origin of these bacteria for human infection. To date, no effective control measures exist to limit Campylobacter colonization in the chicken's intestinal tract. Here, the effect of lyophilization of hyperimmune egg yolk on protection of broilers against C. jejuni was investigated. During an in vivo trial, broiler chickens were prophylactically given feed with lyophilized hyperimmune or non-immunized egg yolk powder starting from day 1 after hatch. At day 11, broilers were inoculated with C. jejuni according to a seeder model. Five days later, all broilers were euthanized and cecal content was examined for C. jejuni colonization. No decrease in C. jejuni colonization was found. The freeze-drying resulted in a 16-fold decrease of the antibody titer in the yolk powder compared to the fresh yolks, presumably caused by structural changes in the antibodies. In conclusion, applying freeze-dried hyperimmune egg yolk failed to protect broilers against C. jejuni colonization, possibly because lyophilization affected the antibodies' functionality.
口服抗体是一种有前途的针对各种传染病的策略。此前，通过在饲料中提供高免蛋黄液进行被动免疫，证明其可降低肉鸡中空肠弯曲杆菌的定植。弯曲菌病是全球报告最多的细菌性食源性动物传染病，而禽肉产品是这些细菌感染人类的首要来源。迄今为止，尚无有效的控制措施可限制鸡肠道中弯曲杆菌的定植。在这里，研究了高免蛋黄液的冻干对保护肉鸡免受空肠弯曲杆菌感染的影响。在体内试验中，从孵化后第 1 天开始，肉鸡预防性地在饲料中添加冻干高免或非免疫蛋黄粉。在第 11 天，根据播种器模型对肉鸡进行空肠弯曲杆菌接种。5 天后，所有肉鸡被安乐死，检测盲肠内容物中空肠弯曲杆菌的定植情况。未发现空肠弯曲杆菌定植减少。与新鲜蛋黄相比，冻干导致蛋黄粉中的抗体滴度降低了 16 倍，这可能是由于抗体结构发生变化所致。总之，应用冻干高免蛋黄未能保护肉鸡免受空肠弯曲杆菌的定植，可能是因为冻干影响了抗体的功能。
