Protein in fish feed is one of the most important nutrients for the healthy growth and development of fish. Protein sources are divided into two main groups: animal and plant. Animal proteins are of high quality and contain all the amino acids that fish need. Vegetable proteins, on the other hand, are cheaper and sustainable. Historically, fish meal and oil were given to both carnivorous and herbivorous fish when they were juveniles to meet their high protein needs. However, due to excessive use, sustainability concerns have arisen, and alternative protein sources have begun to be investigated.