There are two ways of animal fertilization: _ _ and _ _.

Animal fertilization methods include in vivo fertilization and in vitro fertilization.

Animals fertilized in vivo: most of them are reptiles, birds, mammals and other higher animals, including some mollusks, insects and fish, and a few amphibians (such as salamanders).

In vitro fertilization animals: This is a common breeding method for aquatic animals, such as some fish and some amphibians.

So the answer is: in vitro fertilization; In vivo fertilization.