Animal feeding methods can be divided into: 1, oviposition: oviposition is the nutrition provided by yolk for embryo development; 2. viviparous: it is still oviparous in nature, because the nutrition of embryo development is still provided by yolk, which does not depend on the mother to provide nutrition, but the process of fertilized egg development is carried out in the mother; 3, viviparous: viviparous is the nutrition provided by the mother for embryonic development, generally through the placenta.

Introduction of oviparous animals

Birds, reptiles, most fish and insects are almost oviparous. For example, chickens, ducks, fish, frogs, turtles and butterflies are all egg-laying animals. After laying eggs, oviparous animals become animals after hatching, and their nutrition comes from the eggs themselves.

Introduction of viviparous animals

Cone-toothed sharks, star sharks, some poisonous snakes (such as vipers and sea snakes), viviparous lizards and bronchus lizards are viviparous animals. This is a breeding mode formed by animals' long-term adaptation to bad environment, and the actual mother mainly plays the role of protecting and incubating embryos.

Introduction of viviparous animals

Mammals: bats, seals, seals, dolphins, baboons, pangolins, mongooses, anteaters, sea otters, domestic animals, cats, rodents, primates, etc. Higher mammals in vertebrates, such as monkeys, tigers, cows, sheep and wolves, are viviparous.