Digestibility, protein retention rate and ammonia excretion in juvenile fat snook (Centropomus parallelus) fed with different protein levels

作者：Grapiuna de Carvalho Maria Araci; Loureiro Fernandes Luiz Fernando; Gomes Levy de Carvalho^*

来源：Ciencia Rural, 2017, 47(7): e20160369.

DOI：10.1590/0103-8478cr20160369

• crude digestible protein
• fish culture
• nitrogen excretion
• diet

The aim of this study was to determine the level of dietary crude protein (CP) (480, 400, 440, 520 and 560g kg(-1)) in rations for juvenile II fat snook (Centropomus parallelus) that best promotes protein absorption and lower excretion of nitrogenous products. Three experiments were conducted: the first assessed the protein retention rate; the second evaluated ammonia excretion; and the third determined the best digestibility coefficient. The estimated protein retention rate showed a positive quadratic response to dietary CP with maximum retention at the 510.20g kg(-1) protein level, and increasing levels of protein resulted in a greater total ammonia excretion rate in water. The mean apparent protein digestibility coefficient values increased with increasing levels of dietary protein up to 520g kg(-1), where they stabilized. As determined by regression, the level of dietary CP that promotes the best digestibility was 495.62g kg(-1).

• 出版日期2017