Hubei Yasen Biotechnology Co.,Ltd is a professional manufacturer of Acetylisovaleryltylosin tartrate(AIV), it is the first company who own patent of Tylvalosin Tartrate in China. Advanced technology and more than 20 years experience in animal healthy made Yasen is the most reliable manufacture of AIV product. Until now only three factory can produce Acetylisovaleryltylosin tartrate in the worldwide, Yasen are one of them