Study On Thermo-Stable Sugar Glass Vaccine Against Newcastle Disease

Newcastle disease is an acute, highly infectious diseases,which is much serious threat to poultry industry. Newcastle disease live vaccine is widely used in the modern poultry industry and is the most important way to control the disease. Dry freezing technology and cold chain system has been considered as an effective vaccine manufacturing and conservation measures for a long time. The process of production and transportation must rely on cold chain system, causing much inconvenience to practical use. Based on improving vaccine thermostability, this study is intended to use vaccum foam drying method to protect virus from heart of ice core, and restore its biological activity when it dissolved in water again. The37℃aging test was used to filter out heat protection for the formulation and optimization of the drying process, and achieve the goal which can save more than12months and the stability of the vaccine products in the room temperature (25℃).This study is aim to vaccine manufacturing technology of China’s Veterinary study.1. Selection of thermo-stable protectantsSucrose, trehalose, polyvinylpyrrolidone (PVP) were selected at different concentrations in the heat-resistant protective agent, and using orthogonal test formulation design, use vacuum foam method to get live NDV vaccine with the same vacuum drying procedure,drying test. By drying products37℃aging resistance test (preserve samples in37℃for10days and detect NDV EID50), product appearance, viral concentration and residual moisture to filter heat protection formulations, and obtain the concentration of25%of trehalose is best for virus protection. The preliminary experiments of T5A, T5B, T5,T7A and T7B is effective, the titers of T7A、T7B which preservation in the room temperature(25℃) for2month have lost101.0EID50, the titers of T5A、T5B which preservation in the room temperature(25℃) for5month have lost101.0ID50.2. Optimization of the vaccum foam processCombing the further optimized formulation and adjustmenting technology curve, which eventually filter out the recipe T5and T7by residual moisture content and the EID50 of samples, and foam drying three batches of samples to detect temperature tolerance.3. The test of preservation of samples temperature toleranceComparing the samples T5,T7with temperature tolerance,different partition location and similar products,we get the conclusion that samples preservation in the temperature15℃and25℃transport in the4℃and37℃, the titers has lost101.0EID50, the formulation of T5and T7cloud resist the extremely temperature in the short time;different partition location has no significant difference to the drying of samples,the process of drying is stable; freeze-dried products compared with vaccum foam products, although freeze-dried products has highly titer, vaccum foam products has highly titers for preservation in the37℃for10d. For detecting EID50of T5and T7for13month, it is found that T5has lost100.5EID50in the preservation, in the three batches of T7for9month preservation, the titers has lost1.0EID50. the residual moisture content of T5is about2%for9month preservation, and3.5%for12month preservation. While the residual moisture content of T7is about5%for9month preservation, and7%for12month preservation.