Taguchi loss function applied in the tilapia, Oreochromis niloticus fed with different additions of yeast in the diet

Abstract

The experiment was based on observations of 72 juveniles of tilapias of Nile, Oreochromis niloticus, sexually reverted, with an initial medium weight of 37.27 ± 4.92 g, distributed in a completely randomized design for 112 days. This work has evaluated the effect of the introduction of cages with cultivation of tilapia fed 0% (control), 20%, 40% and 60% (groups test) of yeast replacing the traditional sources of diet on weight, survival and feed conversion and also there is no difference between the loss function of Taguchi to the total for the dead fish and discarded and the four balanced rations. The analysis of variance was applied showing that there were no statistical differences (p > 0.05) between the effects of treatments on the survival and feed conversion, but there was a quadratic effect on weight gain of tilapia (Y = 73.39 + 0.173X – 0.0034X2, R2 = 0.9986), concluding that the best level of inclusion of yeast as protein source for juvenile is reversed 25.44%. Taguchi’s loss for the cost of production and for the dead fishes in the treatment T2 = 20%, T3 = 40% and T4 = 60% were lower the group control (T1 = 0%). This result confirms the direction of inclusion of distillers yeast in place of traditional feed source.