Today, 45 years ago, on December 23, 1980 (Lunar Calendar November 17, 1980), the first artificially fertilized American lion was born. On December 23, 1980, the first artificially fertilized American lion was born in the London Zoo in the UK. Three years of research was before the American lion was born. The success of this study was a breakthrough in protecting the reproduction of American lions and other endangered animals. The mother lion injected hormones before artificial fertilization to trigger ovarian excitement. During a period of ninety-five days of conception, the hormone levels in the blood were checked and the uterus was observed using fiber optical testing methods. The little American lion was born weighing about zero kilograms, and a month later reached two-five kilograms, named "P