Proteína bruta e energia digestível em dietas para alevinos de curimbatá (Prochilodus affins)

Abstract

RESUMO -Objetivando-se determinar as exigências de proteína bruta (PB) em função do nível de energia digestível (ED) da dieta para alevinos de curimbatá (Prochilodus affins), foram utilizados 256 peixes com peso inicial de 2,72 ± 0,11 g, mantidos em 32 aquários de 100 L, dotados de abastecimento de água, temperatura controlada e aeração individuais. O experimento foi realizado seguindo-se esquema fatorial 4 x 2 (quatro níveis de PB: 18,0; 22,0; 26,0; e 30,0%, combinados com dois níveis de ED: 2.700 e 3.000 kcal/kg), em um delineamento inteiramente ao acaso, com quatro repetições e oito peixes por unidade experimental. Os peixes foram alimentados ad libitum em duas refeições diárias durante 78 dias. Avaliaram-se o ganho de peso, o consumo aparente de racão, a conversão alimentar aparente, a taxa de crescimento específico, a taxa de eficiência protéica, a eficiência de retenção de nitrogênio, a umidade, a proteína e a gordura corporais e as porcentagens de nitrogênio e de gordura no ganho de peso. Verificou-se que não houve interação dos níveis de PB × ED, à exceção da porcentagem de gordura no ganho de peso. Com o nível de 3.000 kcal de ED/kg, obtiveram-se peixes com maiores níveis de matéria seca, gordura corporal e porcentagem de gordura no ganho de peso. Concluiu-se que a exigência de PB e ED para alevinos de curimbatá é de 26,05% e 2.700 kcal/kg, respectivamente, que corresponde a uma relação ED:PB de 10,36 kcal de ED/g de PB, por proporcionar as melhores respostas em ganho de peso e composição de carcaça.Palavras-chave: curimbatá-pioa, exigências de energia e de proteína, nutrição de peixes, relação energia:proteína Crude Protein and Digestible Energy in the Diets for Curimbatá Fingerlings (Prochilodus affins)ABSTRACT -Two hundred and fifty six curimbatá (Prochilodus affins) fingerlings averaging initial weight of 2.72 ± 0.11 g, stocked in 32 aquariums (100 L) with water renewal, controlled temperature and individual aeration, were used to determine the dietary crude protein (CP) requirements, according to the digestible energy level (DE). The experiment was carried out in to a 4 x 2 factorial scheme (four CP levels: 18.0, 22.0, 26.0 and 30.0% combined with two DE levels: 2,700 and 3,000 kcal/kg), according to a completely randomized design with four replicates of eight fishes. The fishes were fed ad libitum twice a day, during 78 days. Weight gain, apparent feed intake, apparent feed:gain ratio, specific growth rate, protein efficiency rate, nitrogen retention efficiency, humidity, body fat and protein, nitrogen and fat percentage in weight gain were evaluated. No CP × DE levels interaction was observed for any studied variable, except for the fat percentage in weight gain. Fishes fed diets with 3,000 kcal de DE/kg showed higher levels of dry matter, body fat and fat percentage in weight gain. It was concluded that CP and DE requirements for curimbatá fingerlings are of 26.05% and 2,700 kcal/kg, respectively, that correspond to DE:CP ratio of 10.36 kcal DE/g CP, due to the best results of weight gain and ca...

Crude Protein Levels in the Diets of Tambaqui, Colossoma Macropomum (Cuvier, 1818), Fingerlings

“…The response fitted to the LRP model in the present study was consistent with that observed by Bomfim et al (2005), who reported a linear increase in WG in "curimbatá" (Prochilodus affinis) fingerlings, and the occurrence of a plateau at one of the intermediate CP levels evaluated. In contrast, the present results differ from those obtained by Vidal Júnior et al (1998), who found a quadratic effect on weight gain, with variations in dietary protein levels in tambaquis weighing 30-250 g.…”

“…In contrast, Bomfim et al (2005) and Cotan et al (2006) have shown lower moisture levels in "curimbatá" fingerlings and "lambari tambiú" fingerlings, respectively, that were fed diets comprising relatively low levels of CP, compared to those fed higher levels of CP. Body fat levels decreased in a quadratic manner (to yield a minimum value of 2.36%), until an estimated CP level of 26.55% was achieved (Table 3).…”

“…In contrast, Bomfim et al (2005) reported that elevated CP levels in "curimbatá" fingerlings improved PER up to a certain level; suggesting that PER can be improved until the protein requirement is achieved and subsequently decreases with further increases in protein levels.…”

“…The more favorable values for FC observed in fish fed higher levels of CP could be attributed to their higher growth rates (BOMFIM et al, 2005) and particularly their lean muscle tissue, since FC was similar among the various protein levels evaluated. This hypothesis relates to the protein content of muscle tissue on a dry matter basis, which is comparatively lower than that of adipose tissue.…”

“…However, Bomfim et al (2005) reported that feed conversion in "curimbatá" improved in a quadratic manner, owing to variations in protein levels. In other studies, variations in protein levels did not affect feed conversion in Nile tilapia (BOTARO et al, 2007) and tambaqui (VIDAL JÚNIOR et al, 1998).…”