Growth performance and chemical composition of pacus (Piaractus mesopotamicus) fed with vegetable oil sources and alpha-lipoic acid

Abstract

The objective of this study was to evaluate the effects of different oil sources and alpha-lipoic acid levels on pacus performance, chemical composition of fillets and histological changes in the liver. A total of 480 pacu juveniles (3.35 ± 0.78 g), distributed in 24 experimental units (n = 20), were used. Six treatments were delineated in a completely randomized design (CRD), in a 3 x 2 factorial scheme, with three sources of oil (soybean, sesame and linseed) and two levels of alpha-lipoic acid (0 and 0.1%), with four replications. Data were evaluated statistically by analysis of variance (ANOVA) and Tukey’s test (5%). Diets containing linseed oil as the only lipid source provided better indices of final body weight and individual weight gain in pacu juveniles. Crude protein content was higher in fish fillets that fed diets without alpha-lipoic acid. Liver histology was not affected by the experimental diets. In conclusion, linseed oil improved final body weight and individual weight gain on pacus, and alpha-lipoic acid did not affect the performance of the animals, however, its absence promoted higher levels of crude protein in fish fillets.