Capacidade de suporte de alevinos de tilápia em sistema fechado de recirculação de água na fase de berçário

Abstract

The aim of this work was to evaluate parameters such as mass gain and mortality rate in the high densification of tilápia-do-nilo (Oreochromis niloticus) in a water recirculation system, as that said, provinding the storage density into the best results of productive performance. The work was carried out at Laboratório de Piscicultura do Departamento de Zootecnia, na Universidade Federal da Paraíba (UFPB) - CCA, located in the city of Areia, during around 60 days. Four treatments (885, 1107, 1329 and 1550 fingerlings / m3) and four replications were used, totalizing 5608 animals. The productive parameters evaluated were: weight gain and mortality rate. The feed management consisted of commercial feed with 48% PB in the first 45 days and from the 46th day the feed was 1mm with 45% PB. The animals received 10% of their biomass in feed, subdivided into three daily intervals (8, 12 and 16 hours), throughout the experiment. The experiment was evaluated in a completely randomized design (DIC) submitted to repeated averages in time, and the variables were evaluated fortnightly (0: beginning of the experimental period (IPE), 1: at 30 days of IPE, 2: at 45 days of IPE; and 3: at 60 days of IPE) with four replicates each plot, totalizing 16 water boxes in the experiment. Data were submitted to the Shapiro-Wilk normality test and homoscedasticity. Subsequently, the results were submitted to Variance Analysis (ANOVA) with repeated measures in time. For the qualitative data we used the Tukey test at 5% of significance, and for the quantitative, polynomial regression. All statistical procedure employed was developed by free software R (2019). With this, it is concluded that the storage density with better weight gain was 885 fish / m3.