[1]Hetao College;
Bayannur 015000;
China;
[1]Hetao College;
Bayannur 015000;
China;
[1]Hetao College;
Bayannur 015000;
China;
[2]Guidance Station of Livestock Breeding in Tongliao;
Tongliao 028000;
China;
Utilization rate of sows; Reproductive performance; Technical level; Recessive waste; Economic benefit;