Heatproof lyophilized protective agent for live vaccine JXA1-R strain for highly pathogenic porcine reproductive and respiratory syndrome and method for preparing the same

The invention relates to a heatproof lyophilized protective agent for a live vaccine JXA1-R strain for highly pathogenic porcine reproductive and respiratory syndrome and a method for preparing the same. The heatproof lyophilized protective agent for the live vaccine JXA1-R strain for the highly pathogenic porcine reproductive and respiratory syndrome in the invention is composed of the followingcomponents, by weigh: 0.8 to 1.2% of gelatin, 4 to 6% of soybean peptone, 0.5 to 1.5% of glycine, 4 to 6% of trehalose, 1 to 2% of polyvinyl pyrrolidone, 0.5 to 1% of mannitol, and the balance being water for injection; The heatproof lyophilized protective agent is prepared through the steps of high-temperature sterilization, microporous membrane filtration degerming and mixing. The heatproof lyophilized protective agent for the live vaccine JXA1-R strain for the highly pathogenic porcine reproductive and respiratory syndrome in the invention reduces damages to virus activity, the damages being caused by physicochemical factors in lyophilization of the vaccine, and enables virus loss rate to be lower before and after lyophilization with the virus loss rate being no more than 0.2 titer; further, the heatproof lyophilized protective agent satisfies the requirements for low-temperature refrigerated transport of the vaccine and effectively solves the problems such as inconvenient storage, high cost of the vaccine and the like.