Effects of taurine supplementation on growth performance and feed utilization in aquatic animals: A meta-analysis

Abstract

Evidence from many studies indicates that taurine addition may yield an influence on growth in aquaculture animals. Nevertheless, the application efficacy of taurine remains inconsistent across studies. This meta-analysis was conducted to quantify the effects of dietary taurine supplementation on response variables in aquaculture animals, including final body weight (FBW), feed conversion ratio (FCR) and protein efficiency ratio (PER). Hedges' g effect size was computed to quantify the primary outcomes. The sensitivity and subgroup analyses were conducted to assess the robustness of the pooled estimates. Additionally, the effect of different moderators and variability across species was determined by several analyses. Meta-regression was conducted to appraise the effect of different taurine inclusion in diet and taurine content in basal diet on the response variables. The results indicated that taurine supplementation in the diets significantly increased FBW and PER and decreased FCR in fish. Moreover, taurine inclusion yielded larger effects on growth and feed utilization in marine fishes than freshwater fishes. For all species, ‘species’ and ‘basal taurine content in control group’ were two significant moderators on all response variables, and ‘fishmeal content in diet’ as moderator variable was significant in FBW and PER. Interestingly, the beneficial effect of taurine addition on growth performance and feed utilization was significantly reduced as the taurine level in the basal diet increased. In addition, dietary taurine requirement of aquaculture animals was estimated to 0.79% based on broken line regression between total taurine content in diet and FBW effect size.