Abstract The objective of this work was to produce protein hydrolysates from by-products of the Nile tilapia fileting process, and to assess the effects of different hydrolysis times on the antioxidant activity of the hydrolysed animal-based protein, in free form and incorporated into a food matrix. Gutted tilapia heads and carcasses were hydrolysed by Alcalase® for different hydrolysis times producing six hydrolysates. The protein content, degree of hydrolysis, reverse-phase high-performance liquid chromatography, and antioxidant activity by the ORAC, FRAP and TEAC methods were analysed. Three mini-hamburger formulations were produced and the lipidic oxidation of mini-hamburger was determined by TBARS. The protein contained in the residue was completely recovered in the process. The hydrolysates varied in their degree of hydrolysis, but presented similar levels of antioxidant activity. In the mini-hamburgers the hydrolysate was capable of delaying oxidation after 7 days of storage. Hydrolysis of tilapia processing by-products produced peptides may be used in the formulation of functional foods.

The objective of this study was to evaluate the feeding management of pacu juveniles (P. mesopotamicus) under different feeding rates and its relation with productive performance, body composition and hematological characteristics. A total of 300 fish with initial weight of 84.75±4.52 g were distributed in a completely randomized design composed of four treatments (100, 90, 80 and 70% of feed supply) and five repetitions. The amount of feed was stipulated according to the quantity supplied in the treatment until apparent satiation (100%) of the day before. The decrease in the feeding rate to 70% over satiation apparently improves the apparent feed conversion without harming performance, body composition or biochemical and hematological characteristics of pacu juveniles reared in net cages.

No presente trabalho objetivou-se levantar dados sobre a produção orgânica de pescado de água doce. Atualmente, a produção de alimentos orgânicos de origem vegetal é a predominante no mercado, no entanto, a criação de animais com certificação de origem orgânica tem grande potencial e é uma importante ferramenta para agregação de valor aos grãos e subprodutos agroindustriais orgânicos. Quanto à normatização da aquicultura orgânica, os produtores têm se baseado em normas internacionais. No Brasil, a normatização para criação de animais é bastante recente e sua regulamentação foi consolidada por meio da Instrução Normativa Interministerial No28, publicada no dia 8 de junho de 2011 pelo Ministério da Agricultura, Pecuária e Abastecimento (MAPA) juntamente com o Ministério da Pesca e Aquicultura (MPA). Na literatura, são escassos os trabalhos com piscicultura orgânica, mas de acordo com os dados disponíveis, a criação de espécies como a tilápia (Oreochromis niloticus) o pacu (Piaractus mesopotamicus) e o jundiá (Rhamdia sp.) alimentados com rações orgânicas, em diferentes sistemas de cultivo, demonstram resultados bastante otimistas quanto ao sistema de produção, foco deste trabalho.

This study aimed to collect data about organic production of freshwater fish. Today the production of organic food of plant origin is predominant in the market, however, the animal rearing with organic certificate has great potential, and is an important tool for adding value to grains and organic products. Regarding the regulation of organic aquaculture, producers are based on international standards. In Brazil, the norms for breeding are very recent and their regulation was consolidated through Interministerial Instruction No28, published on June 8, 2001 by Ministério da Agricultura, Pecuária e Abastecimento (MAPA) together with Ministério da Pesca e Aquicultura (MPA). In the literature there are few studies with organic fish farm, but according to available data, the rearing of species such as tilapia (Oreochromis niloticus), pacu (Piaractus mesopotamicus) and jundia (Ramdhia sp) fed with organic diet, in different rearing systems, show results quite optimistic about the production system, which is the focus of this work.

O objetivo deste trabalho foi avaliar fontes de fósforo em rações orgânicas, para alevinos e juvenis de tilápia-do-nilo. Utilizou-se o delineamento experimental inteiramente casualizado, com três tratamentos: farinha de resíduos de peixes, fosfato bicálcico e a combinação de ambos, com seis repetições. Duzentos e setenta alevinos e 180 juvenis foram distribuídos em tanques experimentais de 250 e 500 L, respectivamente, e alimentados com rações à base de ingredientes com certificação de origem orgânica contendo 32 e 28% de proteína bruta, respectivamente. Foram avaliados: qualidade da água de cultivo, índices zootécnicos e composição centesimal da carcaça dos peixes. As fontes de fósforo não influenciaram os parâmetros avaliados em alevinos. Juvenis alimentados com a dieta contendo farinha de resíduos de peixes obtiveram melhores índices zootécnicos, em comparação ao fosfato bicálcico, não tendo diferido da combinação entre as fontes. Os valores de fósforo na água ficaram acima dos preconizados pela Resolução 357/2005 do Conama. Para alevinos, é adequado utilizar farinha de resíduos de peixes, fosfato bicálcico ou sua combinação como principal fonte de fósforo e, para juvenis, é adequado utilizar farinha de resíduos de peixes ou a sua combinação com fosfato bicálcico, em rações orgânicas, para melhor desempenho produtivo.

The objective of this work was to evaluate phosphorus sources in organic diets for fingerlings and juvenile Nile tilapia. The experimental design was a completely randomized block, with three treatments: fish waste meal, dicalcium phosphate, and their combination, with six replicates. Two hundred and seventy fingerlings and 180 juveniles were divided into experimental tanks of 250 and 500 L, respectively, and fed diets based on ingredients from certified organic origin containing 32 and 28% crude protein, respectively. Quality of water for cultivation, production indexes and proximate composition of fish carcass were evaluated. Phosphorus sources did not influence the evaluated parameters in fingerlings. Juveniles fed the diet containing fish waste meal had better biological indexes, compared to dicalcium phosphate and did not differ from their combination. The values of phosphorus in the water were above the recommended by the Resolution 357/2005 from Conama. For fingerlings, it is appropriate to use fish waste meal, dicalcium phosphate or its combination as the main source of phosphorus, and, for juveniles, it is appropriate to use fish waste meal or its combination with dicalcium phosphate in organic diets for better production performance.