Development of an immune complex vaccine to control variant infectious bursal disease virus (IBDV) infections in the broiler chicken industry in Canada

开发免疫复合物疫苗来控制加拿大肉鸡行业的变异传染性法氏囊病病毒 (IBDV) 感染

• 批准号: 506071-2016
• 负责人: Gomis, Susantha
• 金额: $ 5.18万
• 依托单位: University of Saskatchewan
• 依托单位国家: 加拿大
• 项目类别: Collaborative Research and Development Grants
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=652133
• 关键词: Development; immune; complex; vaccine; control

Infectious bursal disease virus (IBDV) was first recognized in the USA near the town of Gumboro, Delaware (Gumboro disease). Infectious bursal disease virus belongs to the genus Avibirnavirus of the family Birnaviridae and causes infectious bursal disease (IBD), an acute highly contagious disease of 3- to 6-week-old chickens. The most severe consequence of IBDV infection is the functional loss of the bursa of Fabricius. IBD is one of the most important avian acquired immunosuppressive diseases and has led to large losses to the poultry industry worldwide. IBDVs emerged that could not be controlled by immunization with vaccines prepared from ''classic'' IBDV strains, and were called variants IBDVs (vIBDVs). The control of IBD in Canada has been complicated by the recognition of vIBDVs. Our previous research has identified 43% of broiler flocks or premises (or 52% of barns) in Saskatchewan are infected with vIBDV. It is apparent that flocks with vIBDV infection have a poor feed conversion ratio, high mortality, bursal atrophy and decreased meat production. This has led to an annual loss of over 3.9 million kilograms of broiler production per year in the Saskatchewan broiler chicken industry. This mass of chicken meat lost had a wholesale market value of over $13 million per year. Moreover, in recent years, increased condemnations of broiler carcasses due to bacterial hepatitis was recognized due to immunosuppression. Our research has demonstrated that current vaccination programs against IBDV in the broiler breeder industry in Canada are not effective in controlling vIBDV because of antigenic differences between US-sourced vaccines and vIBDVs circulating in the broiler chicken industry in Canada. Furthermore, we have discovered that current vaccines used in the broiler chicken industry are not able to provide protection against the Canadian vIBDV. Recently, our research revealed an unrecognized phenomenon that the immunization of broilers with vectored vaccine induces immunosuppression that may further increase susceptibility to vIBDV infection. Because of these reasons, we are proposing to develop a IBDV vaccine using Canadian isolates to control vIBDV in the broiler chicken industry in Canada.

传染性囊肿病毒（IBDV）首先在特拉华州Gumboro（Gumboro病）附近的美国被认可。传染性囊病病毒属于Birnaviridae家族的Avibirnavirus属，并引起感染性囊泡病（IBD），这是一种3周至6周大的鸡的急性高度传染性疾病。 IBDV感染最严重的后果是Fabricius的Bursa的功能丧失。 IBD是最重要的禽类获得的免疫抑制疾病之一，并导致了全球家禽业的巨大损失。 IBDV出现了，无法通过用“经典” IBDV菌株制备的疫苗来控制免疫，并且被称为变体IBDVS（VIBDVS）。认识VIBDV的IBD控制使IBD的控制变得复杂。我们以前的研究已经确定了萨斯喀彻温省43％的肉鸡羊群或室内（或52％的谷仓）感染了VIBDV。显然，具有VIBDV感染的羊群的饲料转化率较差，死亡率高，囊肿萎缩和肉产量减少。这导致每年在萨斯喀彻温省肉鸡鸡肉行业每年损失超过390万公斤的肉鸡产量。大量鸡肉丢失的市场价值每年超过1300万美元。此外，近年来，由于免疫抑制，由于细菌性肝炎引起的肉鸡癌的谴责增加了。我们的研究表明，加拿大肉鸡育种行业中针对IBDV的当前疫苗接种计划无法有效控制VIBDV，因为在加拿大肉鸡鸡肉行业中，美国采购的疫苗与vibdvs之间的抗原差异。此外，我们发现肉鸡行业中使用的当前疫苗无法提供对加拿大VIBDV的保护。最近，我们的研究表明，一种无法识别的现象，即对媒介疫苗的肉鸡免疫会诱导免疫抑制，这可能会进一步增加对VIBDV感染的敏感性。由于这些原因，我们建议使用加拿大分离株开发IBDV疫苗，以控制加拿大肉鸡鸡行业的VIBDV。