γ—射线灭蠅法在美国东南部,家畜群常受到一种金蝇(Chrysomyia hominivorax)的威胁。家畜身上有了瘡口,金蝇便在这里下卵30个到100个,卵孵化成蛆,蛆就往肉里钻食,不出10天就能讓一条成年的公牛死亡。对此,喷药或涂油膏都没大用,因为药效最久只能維持一星期。有一个間接办法,就是减削金蝇的繁殖。其法:在一閉室内, Gamma ray-killing flies In the southeastern United States, livestock herds are often threatened by a Chrysomyia hominivorax. There is a sore on the body of a fowl, and gold flies drop eggs 30 to 100 here. The eggs hatch into maggots and the maggots dabble in the flesh, killing an adult bull in 10 days. In this regard, spray or ointment are not great, because the longest lasting efficacy can only be maintained for a week. There is an indirect way is to reduce the reproduction of goldfly. The law: in a closed room,