Heterogeneous Growth Prediction in Farmed Tilapia

Abstract

This study displays the application of the quantile regression theory to predict the size heterogeneity of cultured organisms. The analysis was applied to empirical data of the tilapia cultured in freshwater. Tilapia was cultured at four diets (50%, 80%, 100%, and Satiation). The quantile regression (QR) demonstrated to successfully model the size heterogeneity in tilapia (p<0,05; u<0,20), due to the feeding strategies effect. These results indicate tilapia fed an 80% ration size simulated a maximum biomass of 2,345.17 and 2,853.38kg at the harvest size of 200-300g (at 180 days) and 300-400g (at 210 days). The simulation of the quantile curves at a higher production scale allowed an estimate of the biomass distribution according to different market sizes, this strengthens management decision making in tilapia aquaculture. Implications of quantile regression and size heterogeneity in aquaculture are presented here.