Productive performance of Nile tilapia fed levels of digestible protein, energy and choline.

• Grant number: 10/10469-8
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2010
• End date: August 31, 2011
• Field of knowledge: Agronomical Sciences - Animal Husbandry - Animal Nutrition and Feeding
• Principal Investigator: Margarida Maria Barros
• Grantee: Eric Portilho de Araujo
• Host Institution: Faculdade de Medicina Veterinária e Zootecnia (FMVZ). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil

Abstract

The increased demand for high protein food; the increasing in tilapia aquaculture over the last decade; the lack of studies in protein and energy requirement, mainly in intensive conditions and the lack of choline studies minimizing fatty liver in fish. This study aimed at evaluates the growth performance of Nile tilapia fed diets formulated to contain different digestible protein and energy and choline. This experiment will be conducted at Faculdade de Medicina Veterinária e Zootecnia, UNESP, Univ. Estadual Paulista , Câmpus de Botucatu, DMNA, AquaNutri. Juvenile of Nile tilapia, Supreme strain, from Fernandes Aquaculture Farm - São Manuel/SP, will be selected for uniform size. They will be allocated into net cages (200 L each) during the adaptation period. After reach 60g they will be randomly distributed into 40 aquaria (250 L each), at a density of six fish/aquarium in a closed recirculation system. The system will be supplied with a heater and temperature will be kept at 26.0 ± 1.0ºC. Each experimental diet will be randomly fed to fish four times a day. The experimental design will be a factorial 5x2x2, with five levels of protein (24.0; 26.0; 28.0; 30.0 e 32.0% of DP), two levels of energy (3200 e 3600 kcalED/kg of diet) and two levels of choline (0.0 e 1000 mg/kg of diet). Diets will be formulated to contain amino acids according to Furuya et al. (2001) and others nutrients according NRC (1993). After, diets will be processed and dried at 55°C. Diets will be distributed randomly among the tanks, two tanks per treatment and eight fish per tank. Fish will be identifying with microchip; therefore each fish will be considered a replication, with eight replications/aquaria and sixteen/treatment. Water temperature will be measure daily and pH, dissolved oxygen and ammonia, weekly, using YSI 556®. Accumulated wastes will be removed by siphoning. Chemical analysis will be determined at Laboratório de Bromatologia of Departamento de Melhoramento e Nutrição Animal da FMVZ, UNESP, Câmpus de Botucatu. Data will be analyzed using a two-way Anova technique for a 5x2x2 factorial experiment using SAS statistical software.