Prevention of Inclusion Body Hepatitis (IBH) in the broiler Chicken Industry: Optimizing Two Prototype Fowl Adenoviral Vaccines

包涵体肝炎（IBH）是一种急性病毒性疾病，其特征是突然发病，死亡率高，严重的肝坏死，显微镜下可见核内包涵体。IBH是由几种不同血清型的禽腺病毒（FAdV）引起的。自2000年以来，IBH已成为加拿大肉鸡业的头号经济重要疾病。虽然萨斯喀彻温省仅占加拿大肉鸡行业销售额的4%， 由于IBH的死亡率，它每年损失超过30万美元。因此，加拿大肉鸡行业的生产力损失总额要高得多，估计为数百万美元。我们能够确定加拿大IBH的爆发主要是由于FAdV从父母那里垂直传播。我们还能够证明FAdV的五种主要血清型在加拿大引起IBH，并且通过用灭活或活FAdV疫苗接种肉鸡育种者，可以显著保护肉鸡免受IBH。虽然我们能够在工业界和NSERC的财政支持下生产两种针对IBH的原型疫苗，但我们需要优化这些灭活和活FAdV疫苗，以提高其效力，然后才能生产并在加拿大肉鸡行业上市。这项研究将优化活的和灭活的FAdV疫苗，并提高我们的理解FAdV脱落和突变的变化，在分子水平上。

Inclusion body hepatitis (IBH) is an acute viral disease in chickens characterized by sudden onset of high mortality with severe hepatic necrosis with microscopic intranuclear inclusion bodies. IBH is caused by several different serotypes of fowl adenoviruses (FAdV). Since 2000, IBH has emerged as the number one economically important disease for the broiler chicken industry in Canada. Although Saskatchewan has only 4% of the Canadian broiler chicken industry sales, it loses over $300,000/year due to mortality from IBH. Hence, the total Canadian broiler industry loss of productivity is much higher, estimated in millions of dollars. We were able to identify that outbreaks of IBH in Canada are primarily due to vertical transmission of FAdVs from their parents. We were also able to demonstrate that five major serotypes of FAdVs cause IBH across Canada and there is a significant protection of broilers against IBH by vaccinating broiler breeders with either inactivated or live FAdV vaccine. Although, we were able to produce two prototype vaccines against IBH with financial support from industry and NSERC, we need to optimize these inactivated and live FAdV vaccines to improve their efficacy before they can be manufactured and become commercially available to the broiler industry in Canada. This proposed research will optimize both live and inactivated FAdV vaccines, and improve our understanding of FAdV shedding and mutational changes of FAdV at the molecular level.