Efeito da proteína vegetal na qualidade de água dos efluentes da carcinicultura

Abstract

The feeding is one of the main factors that, associated to the characteristics of the water as temperature, oxygen, salinity, standard of circulation and water renewal, as well as the natural productivity, influence the development and survival of the species. Had been carried through 16 intensive cultives in youthful internal tanks with of Litopenaeus vannamei with 2,86 ± 0,09 g, at Empresa Pernambucana de Pesquisa Agropecuária (IPA) in Ipojuca - PE, a density of 33,3 animais/m2. The shrimps had been submitted on four diets with four repetitions, in different animal and vegetal protein levels respectively: A) 75 and 25%; B) 50 and 50%; C) 25 and 75% and D) commercial ration, during 60 days of experiment, to evaluate the growth, profit of weight, survival, alimentary conversion and to quantify the influence of the vegetal protein source in the effluent ones of the culture verified by the variance analysis (ANOVA), complemented with the test of Tukey (P<0,05). The stability of the rations was evaluated with the immersion of peletes in seawater during the times of 30, 60, 90, 120, 150, 180, 210, 230, 260, 290, 310 and 330 minutes. There were no significant differences (P<0,05) in relation to the gain of weight of 4,56 g; 4,60 g and 4,28 g, growth of 7,83 cm; 7,79 cm and 7,62 cm and survival 4.35%, 59.61% and 42.31% with the rationsA, B and C, respectively. However, ration D with 5,44g, 8,12 cm and 93.27% was statisticaly better in these analyzed parameters. The variable of analyzed of water quality are inferior to the limits allowed for the GAA, not having statistics difference (P<0,05) between all the tested rations. During 30, 60, 120, 150, 180, 240 and 360 minutes the ration A, revealed with lesser values of loss of dry substance of pelets with results of 2,22; 4,31; 6,80; 8,0; 9,43 and 10.97%, being different significantly (P>0,05) of rations B, C and D. In the time of 90, 210, 270, 300 and 330 minutes did not have difference statistics between all the tested rations. A time that did not have difference statistics in the parameters of water quality, taken care of the nutritional requirements of the species, these rations can become viable when the shrimps will be cultivated in fisheries, for the alive food availability.