Seeking the best alternatives: A systematic review and meta-analysis on replacing fishmeal with plant protein sources in carnivorous fish species

The price of fishmeal (FM) has been increasing continuously due to the expansion of the gap between its stable production and rising demand. Therefore, plant protein sources are widely applied in the aquaculture industry to accomplish the protein requirement of farmed fish species. However, the massive number of results produced under various experimental conditions appended challenges for comprehensive summarization and comparison of the effects of plant protein sources on carnivorous fish species. Thus, a systemic review and meta-analysis were conducted to compare the impacts of various plant protein sources on growth, feed utilization efficiencies, blood lipid, and liver health of representative carnivorous species. Supported by the data from 256 articles, our results indicated that Atlantic salmon, African catfish, Black seabass, and Hybrid striped bass were better at utilizing plant protein sources than Grouper and Japanese seabass. Cottonseed and lupin proteins were promising protein alternatives, while rapeseed showed significant growth suppression effects for these carnivorous fish species. Besides, deep processing methods such as fermentation and enzymolysis alleviated undesirable consequences effectively when less than half of FM was replaced by plant protein sources. Moreover, the optimal plant protein sources are discussed for each fish species. Overall, this article depicts the impact patterns of major plant protein sources on carnivorous farmed fish species and lays a solid foundation for further investigation on mechanisms for improving plant protein utilization.