02146naa a2200217 a 450000100080000000500110000800800410001910000220006024501130008226000090019552015160020465300190172065300140173965300120175365300120176570000190177770000220179670000170181870000180183577300750185311300642020-10-16       2020    bl uuuu     u00u1 u    #d1 aVICENTE, L. R. M.  aNILE TILAPIA NURSERY IN A BIOFLOC SYSTEMbEVALUATION OF DIFFERENT STOCKING DENSITIES.h[electronic resource]  c2020  aThis trial aimed to evaluate the growth performance and hematological parameters of Nile tilapia (Oreochromis niloticus) GIFT strain during nursery using different stock densities in a biofloc system. The experiment was conducted in circular tanks (400 L) with sexually reversed fish, weighing 6.74 ± 0.37 g, over a period of 35 days. Five treatments with three replicates each were used in a completely randomized design. The treatments were as follows: T1 (200 fishes m-3); T2 (300 fishes m-3); T3 (400 fishes m-3); T4 (500 fishes m-3), and T5 (600 fishes m-3). The fishes were fed four times a day, following a feed table for this species, with adjustments according to fish biomass. The water quality parameters total ammoniacal nitrogen, and unionized ammonia showed a significant difference (p&lt0.05) between the treatments with lower (T1) and higher stocking densities (T4, T5). Alkalinity was significantly higher in treatments with higher densities (T4 and T5). For hematological parameters, the number of thrombocytes was higher in T5. Hemoglobin concentration was significantly lower in T5 than in T3. The best productive indexes were found in T4, presenting final biomass of 9915.16 ± 14.80 g m-3, apparent feed conversion rate of 1.11 ± 0.02, mean survival of 95.75 ± 0.75%, and daily mean weight gain of 0.43 ± 0.07 g. Overall, the Nile tilapia nursery in a biofloc system showed higher individual growth at densities up to 300 fishes m-3 and increased stocking density up to 500 fishes m-3.  abiofloc system  adensities  anursery  aTilapia1 aOWATARI, M. S.1 aMOURINO, J. L. P.1 aSILVA, B. C.1 aVIEIRA, F. N.  tBOLETIM DO INSTITUTO DE PESCA , São Paulogv. 46, n. 2, p. 1-9, 2020.