Monitoring serologic response to single in ovo vaccination with an immune complex vaccine against infectious bursal disease in broilers

The infectious bursal disease (IBD) virus is one of the most resistant and prevalent virus worldwide in the poultry industry, being vaccination the main tool to control the disease. For this reason, consistent and uniform immunization of broiler flocks against IBD is necessary to avoid the disease spreading. The aim of this study was to apply and assess an epidemiologic mapping tool focused on the immunization by in ovo single broiler vaccination using an immune complex IBD vaccine. With this regard, 7,576 serum samples were collected from 603 broiler flocks raised in 354 Spanish farms. To do so, blood samples were randomly collected from birds with ages between 35 to 51 d, and the serum was analyzed by ELISA. The results obtained from this study suggested a high uniform immunization against IBDV and a protective immunization between 35 and 51 d of age, with mean titer values ranging between 6,331 and 7,426. In addition, seroprevalence titer data of this large-scale monitoring study fitted a polynomial equation with a R(2) value of 0.77, helping to explain and predict the humoral response to IBD vaccination. This seroprevalence map was applied to broiler production and was based on business intelligence tool that incorporates newly developed mapping tool to cover the need of having real-time information of humoral response to IBD vaccination and could be an effective tool for veterinary services to control and prevent IBD.