Effects of feeding regimes and dietary energy on the production performance, plasma immune parameters and expression of genes involved in the TOR/S6K1 pathway of juvenile hybrid grouper (Epinephelus fuscoguttatus ♀ × Epinephelus lanceolatus ♂)

• Published in: Aquaculture 2023-06, Vol.571, p.739457, Article 739457
• Main Authors: Yin, Haoran, Deng, Yinsheng, Liang, Chengjin, Geng, Lina, Zhang, Jinfeng, Wu, Xiaoyi, Zhou, Zhiyu, Zhai, Haoyun, Cai, Qinxiao, Zhang, Lu, Rossi, Waldemar
• Format: Article
• Language: English
• Subjects: aquaculture; body weight; diet; energy; Epinephelus fuscoguttatus; Epinephelus lanceolatus; feed conversion; feed intake; Feeding regime; grouper; Growth; growth performance; Hybrid grouper; hybrids; hypothalamus; Immunity; immunoglobulins; juveniles; lysozyme; neuropeptides; protein efficiency ratio; TOR/S6K1 pathway; weight gain
• ISSN: 0044-8486; 1873-5622
• DOI: 10.1016/j.aquaculture.2023.739457

The aim of this research was to assess the effects of different feeding regimes on growth performance, plasma immune indices and related genes' expression of hybrid grouper (Epinephelus fuscoguttatus ♀ × Epinephelus lanceolatus ♂) juveniles fed two dietary energy levels. A 3 × 2 factorial experiment was designed including three feeding regimes (two meals a day, one meal a day, one meal every two days; designated as 2 M, 1 M, 2DM) and two dietary available energy levels (3.4 and 3.6 kcal/g; designated as E3.4, E3.6), with three replicates per treatment. Juvenile hybrid grouper (average initial body weight: 19.39 ± 0.04 g/fish) were cultured for 6 weeks in 18 floating cages (125 cm × 80 cm × 40 cm) placed in six concrete ponds sharing the same water source. Results revealed that the 2 M and 1 M treatments had significantly higher weight gain rate (WGR), protein efficiency ratio (PER), expression of hepatic IGF-1, TOR, and S6K1 than the 2DM treatment (P