Taurine Growth Effects - Determining Optimum Taurine Supplementation Levels for Plant Proteins Incorporated into Marine Finfish Feeds using Juvenile Sablefish Anoplopoma fimbria

Taurine, an amino sulfonic acid, has important roles in osmoregulation, bile acid conjugation, membrane stabilization and calcium homeostasis in vertebrates. Though many animals biosynthesize taurine, felines and some marine finfish have low cysteine sulfinate decarboxylase (CSD) activity, limiting their ability to produce taurine. In cats, a diet devoid of taurine will cause blindness and multiple birth defects. Thus, taurine is an essential nutrient for the cat. The capacity of aquaculture finfish to biosynthesize taurine depends on the species. Although the underlying physiological processes are not yet understood, recent studies have shown that taurine improves growth of fish such as yellowtail, Japanese flounder, sea bream, and cobia. Though a promising aquaculture species, it is unknown whether sablefish can synthesize taurine or whether they must obtain it through their diet to achieve optimal growth.

While ample amounts of taurine are found in many rendered animal proteins, including fishmeal, taurine is absent from plant proteins recently employed in fish feeds. Studies on yellowtail, red sea bream, and rainbow trout fed low (or zero) fishmeal diets saw improved growth with taurine supplementation. Taurine limited processes are a potential barrier to the optimum growth and successful transition of marine finfish species from currently available, fishmeal based feeds to alternative, more sustainable, plant-based feeds.
Fish weights and lengths for study.