RESEARCH PROGRESS AND SEVERAL KEY SCIENTIFIC QUESTIONS IN STUDIES OF FISH EGG QUALITY

Egg quality is a complex biological characteristic, which determines the reproductive capacity of females. Fish egg quality refers to the fertilizing ability of eggs and the ability to support the normal development of embryos and larvae. It is directly related to the formation of fertilized eggs, the early development of embryos, and the survival and development of larvae and juvenile fish. It is the key-link that determines the success of fish breeding and breeding efficiency. It is an important prerequisite for the development of aquaculture industry to evaluate egg quality objectively and accurately, to improve egg quality and to obtain a large number of mature eggs with high quality. In theory, fish egg quality is determined by all deposited maternal materials and their spatial and temporal distribution patterns in the egg. In this paper, the research status of fish oogenesis, maturation and the evaluation criteria of egg quality are summarized. In addition, the regulation of egg quality by maternal factors based on zebrafish model is highlighted. Finally, the key scientific questions involved in fish oocyte quality that need to be studied and solved are proposed, i.e., the main biological events that determine and are affected by egg quality, including oogonia-to-oocyte transition, oocyte-to-egg transition, egg-to-embryo transition, embryo-to-larval transition, and larval-to-juvenile transition.