Redução da proteína em dietas para tilápias-do-nilo por meio da suplementação de aminoácidos com base no conceito de proteína ideal

Abstract

RESUMO -Este trabalho foi realizado para avaliar os efeitos da redução da proteína da dieta, por meio da suplementação com aminoácidos sintéticos, sobre o desempenho produtivo, a digestibilidade e o diâmetro da fibra muscular de tilápias-do-nilo. Os aminoácidos (lisina, metionina, treonina e arginina) foram suplementados de forma a manter o perfil de aminoácidos da dieta-referência. Foram utilizados 160 peixes com peso vivo médio inicial de 105,7 ± 2,5 g, distribuídos em 16 tanques (1 m 3 cada) e alimentados com dietas contendo 26,74; 25,82; 23,09 ou 22,16% de proteína digestível durante 110 dias. Não foi observado efeito dos níveis de proteína nas dietas sobre o ganho de peso diário, o índice hepatossomático, a gordura visceral, o rendimento de filé, os teores corporais de umidade, proteína bruta e cinzas, o teor de cinzas no filé, a taxa de sobrevivência e o diâmetro das fibras do músculo dorsal. Com a redução dos níveis de proteína na dieta, foi observada redução linear dos coeficientes de digestibilidade aparente da energia bruta, proteína bruta, extrato etéreo e fósforo das dietas. Houve efeito quadrático dos níveis de proteína sobre a conversão alimentar, a taxa de eficiência proteica, a retenção de nitrogênio, o nitrogênio excretado, a umidade no filé, a gordura corporal e no filé e proteína no filé, de modo que os melhores valores foram estimados com 24,53; 24,25; 24,04; 25,15; 24,67; 24,14; 24,34; 25,11% de proteína digestível, respectivamente. É possível reduzir, de 26,74 para 24,53%, a proteína digestível em dietas para tilápias-do-nilo na fase de 100 a 500 g. Palavras-chave: aminoácido, desempenho, digestibilidade, fibra muscular, peixe Protein reduction in diets for Nile tilapia by amino acids supplementation based on the ideal protein concept ABSTRACT -The objective of this work was to evaluate the effects of reduction of protein in diets for Nile tilapia by supplementation of synthetic amino acids on performance, digestibility and diameter of muscle fiber of Nile tilapias.The amino acids (lysine, methionine, threonine and arginine) were supplemented to keep the profile of amino acids in the reference diet. It was used 160 fish with initial live weight of 105.7 ± 2.5 g, distributed in 16 tanks (1 m 3 each tank) fed diets containing 26.74; 25.82; 23.09 or 22.16% of digestible protein for 110 days. It was not observed any effects of protein levels in the diets on daily weight gain, hepatosomatic index, visceral fat, fillet yield, carcass humidity, crude protein and ash, fillet ash, survival rate and on the white muscle fiber diameter. A linear decrease on apparent digestibility coefficients, gross energy, crude protein, ether extract and phosphorus was observed when protein levels in the diet were reduced. There was a quadratic effect on feed conversion ratio, protein efficiency rate, nitrogen retention, nitrogen excretion, fillet humidity, carcass and fillet fat and fillet protein, in which the best-fit responses were estimated with 24.53, 24.25, 24.04, 25.15, 24.67, 24.14, 24.34 IntroduçãoA...

Feeding Frequency of Nile Tilapia Fed Rations Supplemented With Amino Acids

“…However, the value observed in the present study was lower than those observed by Furuya et al (2000) and Bomfim et al (2010), who reported 8.7% and 8.9%, respectively. In addition, the specific growth rate of the present study was greater than the values between 3.2% and 5.5% reported by and Righetti et al (2011). These researchers suggest that the use of fish feed formulated with a moderate reduction in the recommended crude protein levels (of 32%) (NRC, 1993;FURUYA et al, 2000;NRC, 2011), that based on the ideal protein concept has also been supplemented with commercial amino acids, does not adversely affect the performance of fish, even at low feeding frequencies (twice daily).…”

“…In addition, studies have suggested that more precise supplementation with commercially-available limiting amino acids to meet the nutritional requirements of Nile tilapia (FURUYA et al, 2005;BOTARO et al, 2007;BOMFIM et al, 2008;QUADROS et al, 2009;RIGHETTI et al, 2011), tambatinga (ARARIPE et al, 2011), and rainbow trout (YAMAMOTO; SUGITA; FURUITA, 2005) could effectively reduce the use of excessive levels of other amino acids in the feed, thereby reducing levels of nitrogen excreted into the environment.…”

“…This could be attributed to the possibility of leached amino acids in the aquatic environment, higher rates of gastric emptying, and faster absorption of commercial amino acids, which can lead to temporary imbalance in the profiles amino acids that are needed for protein synthesis (SCHUHMACHER; WAX; GROPP, 1997;ZARATE et al, 1999;RONNESTAD et al, 2000;AOKI;AKIMOTO;WATANABE, 2001;NWANNA et al, 2012).…”

Crude protein reduction with amino acid supplementation in tambaqui fingerling diets

“…Given that the diets were provided as five daily meals and successive transfers, it is possible that this procedure matched the differences between the rates of industrial amino acid absorption and those obtained from protein sources (SOUZA et al, 2014). The higher the feeding frequency, the better the match between the concentration of industrial amino acids and those obtained from protein sources, therefore resulting in a higher protein efficiency, which is consistent with the results observed in this study (RIGHETTI et al, 2011;SOUZA et al, 2014;SANTOS et al, 2014).…”

Histologia hepática e produção em tanques-rede de tilápia-do-nilo masculinizada hormonalmente ou não masculinizada

“…A quantidade de proteína da dieta depende de inúmeros fatores inerentes ao peixe, às condições ambientais de criação e à própria dieta. Vários estudos têm buscado o melhor regime de alimentação quanto à qualidade e aos níveis proteicos, com o objetivo de redução dos custos com alimentação, sem causar danos metabólicos aos peixes (Al Hafedh, 1999;Hayashi et al, 2002;Furuya et al, 2005;Botaro et al, 2007;Righetti et al, 2011;Loum et al, 2013).…”