Elevated sea temperature combined with dietary methionine levels affect feed intake and appetite-related neuropeptide expression in the brains of juvenile cobia (Rachycentron canadum)

This study aimed to determine the impact of elevated temperature combined with different levels dietary methionine concentrations on feed intake (FI) and brain expression selected neuropeptides one receptor involved in appetite control juvenile cobia (approximately 3.7 g body weight). The genes studies were neuropeptide y, npy; agouti-related protein, agrp ; cocaine- amphetamine-regulated transcript, cart; cholecystokinin, cck melanocortin 4 receptor; mc4r . reared at typical sea water Vietnam (30 °C) (34°C; as predicted scenarios climate change). fish fed diets methionine: deficient (M9; 9.1 g/kg), sufficient (M12; 12.8 g/kg) surplus (M16, 16.8 for 6 weeks (triplicate tanks per treatment). Both concentration affected FI cobia. Dietary deficiency (i.e., M9) reduced Temperature significantly influenced mRNA , cart Expression orexigenic npy was consistently higher before meal than after all both temperatures. At 30°C, prefeeding correlated increased FI. interaction between significant (P<0.05). There agrp, 34°C which a lower In conclusion, feeding, and/or cart, mc4r. suggests that these well are actively adjusting compensate changing energetic demands, metabolic adjustments due variable availability temperature.