In addition to age, prolonged light time, water bath and nutritious feed are also indispensable conditions for birds to courtship in estrus. The main purpose of water bath is to wash feathers, keep them clean, and contribute to health and growth. In addition, there is one of the biggest effects, which is to promote estrus. The use of millet balls can promote estrus of birds during spawning. The method of making millet balls is very simple. In a useful vessel, put two matchboxes of millet, add 1 egg yolk, stir and mix evenly, and then pour the mixed millet on paper to dry. Although some birds perform well in estrus, and the male and female birds are very affectionate, this does not mean that they can mate normally. The main factor affecting the normal mating of birds is the environment. In other words, birds will not mate in unfamiliar and unaccustomed environments. Therefore, in the estrus and spawning period of birds, we should try to avoid changing the environment and replacing or moving cages. Let the birds live in a comfortable and accustomed environment, then they will have mating behavior, and the females will produce fertilized eggs. After selecting pairs of parent birds, they should be fed separately in special breeding cages or larger breeding boxes. Once they enter estrus, they will become very lively, constantly singing, chasing and jumping, and need more room for activities. Therefore, if possible, a larger breeding cage should be prepared for caged birds to facilitate breeding. Before keeping caged birds, it is advisable to keep male and female birds separately (except pearl birds and white-waisted wenbirds). When the female bird is in full estrus, the male bird will be released into the female cage, which is easy to succeed. You can also put two cages together for a few days and then close them again, so that the male and female birds can get to know each other well. Until the cage is estrus and intimate, it is more beneficial to close the cage and mate. For most birds, the formation of eggs has an impact on sexual behavior. After the female bird is courted by the male bird, the reproductive organs in the body are stimulated, and then sexual activity and oviposition behavior occur. In the breeding season such as spring and summer, birds can lay eggs on time, and the number of ovaries they produce is relatively fixed.