Resumo
The adequate diet of Nile tilapia in their growth early stages is fundamental to the success of culture subsequent stages. The goal of the present work was to evaluate the Nile tilapia growth fed with different diets, and to morphometrically characterized the gastrointestinal tract of this species. The treatments consisted of three diets: (D1) natural food, (D2), commercial feed and (D3) commercial feed + natural food. In the qualitative phytoplankton analysis, there was greater representation of the genus Chlorella, while zooplankton community analysis revealed greater number of Brachionus rotifer. Growth and survival in D2 and D3 did not reveal differences (p > 0.05), while in D1, the results were significantly lower (p < 0.05). The gastro-somatic and entero-somatic indices, and the intestinal quotient revealed higher values when only natural food was available. Nile tilapia reached best zootechnical performance when commercial feed was included in the diet. The intake of natural and/or artificial food is related to the growth and development of the gastrointestinal indices, emphasizing that these indicators can be altered by the type of feeding.
A dieta adequada de tilápia do Nilo em suas fases iniciais de crescimento é fundamental para o sucesso das etapas subsequentes do cultivo. O objetivo do presente trabalho foi avaliar o crescimento de tilápias do Nilo alimentadas com diferentes dietas e caracterizar morfometricamente o aparelho gastrintestinal da espécie. Os tratamentos constaram de três dietas: (D1) alimento natural, (D2) ração comercial e (D3) ração comercial + alimento natural. Na análise qualitativa do fitoplâncton, observou-se maior representação do gênero Chlorella enquanto a análise da comunidade zooplanctônica revelou maior número de rotíferos do gênero Brachionus. O crescimento e a sobrevivência em D2 e D3 não apresentaram diferenças (p > 0.05), enquanto em D1 os resultados foram significativamente inferiores (p < 0.05). Os índices gastrossomáticos, enterossomáticos e o quociente intestinal apresentaram, de uma maneira geral, valores superiores nos tratamentos que utilizaram alimento natural na dieta. Tilápia do Nilo alcançou melhor desempenho zootécnico quando a ração comercial foi incluída na dieta. A ingestão do alimento natural e/ou artificial está relacionada com o desenvolvimento dos índices gastrintestinais, reforçando que estes indicadores podem sofrer mudanças ocasionadas pelo tipo de alimentação.
Assuntos
Animais , Fitoplâncton , Zooplâncton , Tilápia/crescimento & desenvolvimento , Ciclídeos/crescimento & desenvolvimento , Trato Gastrointestinal , DietaResumo
The adequate diet of Nile tilapia in their growth early stages is fundamental to the success of culture subsequent stages. The goal of the present work was to evaluate the Nile tilapia growth fed with different diets, and to morphometrically characterized the gastrointestinal tract of this species. The treatments consisted of three diets: (D1) natural food, (D2), commercial feed and (D3) commercial feed + natural food. In the qualitative phytoplankton analysis, there was greater representation of the genus Chlorella, while zooplankton community analysis revealed greater number of Brachionus rotifer. Growth and survival in D2 and D3 did not reveal differences (p > 0.05), while in D1, the results were significantly lower (p < 0.05). The gastro-somatic and entero-somatic indices, and the intestinal quotient revealed higher values when only natural food was available. Nile tilapia reached best zootechnical performance when commercial feed was included in the diet. The intake of natural and/or artificial food is related to the growth and development of the gastrointestinal indices, emphasizing that these indicators can be altered by the type of feeding.