<b>Underwater structures for periphyton in bioflocs tanks for Nile tilapia submitted to feed restriction

Abstract

ABSTRACT. The objective of the present work was to assess the possible benefits of the installation of underwater structures for periphyton in bioflocs tanks for Nile tilapia, Oreochromis niloticus, submitted to feed restriction (artificial diet). The experimental treatments evaluated were: (1) BFT: bioflocs technology for aquaculture with no feed restriction; (2) BFT-30: the same as (1) but with feed restriction at 30%; (3) BP: biophyton technology for aquaculture, that is, integration between bioflocs and periphyton in the same rearing unit, with no feed restriction; (4) BP-30: the same as (3) but with feed restriction at 30%. The underwater structures for periphyton in the BP and BP-30 tanks were not able to reduce the concentrations of ammonia, nitrite, nitrate and reactive phosphorus in the water to same respective level found in the BFT and BFT-30 tanks. The underwater structures for periphyton in the BP and BP-30 tanks have not significantly affected fish growth performance. No benefits were obtained by the installation of underwater structures for periphyton in bioflocs tanks submitted to feed restriction on water quality, water microbiology and tilapia growth performance.

Taxa De Arraçoamento Para Jundiás Cultivados No Sistema De Bioflocos / Feeding Rates for Silver Catfish Rearing in Biofloc System

“…O sistema de biofloco ainda é incipiente na piscicultura, principalmente no cultivo de espécies nativas. Já os estudos que avaliam o biofloco como uma fonte de alimentação suplementar para o peixe cultivado vem crescendo principalmente com o intuito de minimizar os custos de produção (CAVALCANTE et al, 2017 Cento e oito jundiás (24,75 ± 3,16 g) foram aclimatados em sistema de bioflocos, durante sete dias. Posteriormente, os peixes foram distribuídos nos tanques (12 peixes por unidade) e alimentados com ração comercial extrusada, com 32% de proteína bruta, duas vezes ao dia (às 8:00 e 17:00 h).…”