Influence of temperature on growth, feed consumption and chemical composition in the muscle of Pacu Piaractus mesopotamicus

The zootechnical performance of fish can be influenced by temperature through the induction of metabolic changes that are likely to affect growth and body composition. Thus, the objectives of this study were: (a) to examine the influence of five different temperatures (18, 21, 24, 27 and 30 degrees C) on growth performance and metabolic parameters and (b) to evaluate the relationship of the protein efficiency ratio (PER) with the fillet proximate composition of Pacu juveniles. Growth and feed consumption (FC) were positively correlated with temperature (R-2 = .95), while PER and FC were negatively correlated with temperature (R-2 = .89). For the fillet composition, ethereal extract increased, and moisture decreased with the temperature. Protein content was lowest at 18 and 30 degrees C and highest at 21, 24 and 27 degrees C. The robust adjusted curve between PER and fillet protein content in relation to temperature showed the best result at 21 degrees C. The obtained results indicate that Pacu juveniles reared between 21 and 27 degrees C showed better protein efficiency with regard to FC, and this effect reflected better meat quality.