Interactive impacts of rosemary oil and amylase-lipase enzymes on Liza ramadaperformance, ammonia excretion, digestion, serum biochemistry and intestinal histomorphology

An 84-day growing trial was conducted to evaluate Liza ramada'sperformance and health. Five treatments (3 replicates) were tested using anexperimental diet (ED) supplemented with rosemary oil (RO) or RO and amylase-lipase (AL) enzymes as follows; (T1) fish-fed ED with no additives “control”; (T2) fish fed ED containing 0.5kg ton-1RO; (T3) fish fed ED containing 0.5kg RO and 0.917kg AL ton-1; (T4) fish fed ED containing 1 kg ton-1RO; and (T5) fish fed ED containing 1 kg RO and 0.917kg AL ton-1. A total of 150 Liza ramadafish (7.30±0.01 g/fish) were housed in 15 hapas (10 fish/hapa) and fed tested diets twice daily at 4-3% of body weight. Findings revealed that fish that received RO and RO+AL supplemented diets had lower NH3 levels and higher survival rates (24.32, 51.34, 37.83, and 54.05%) in groups T2, T3, T4, and T5, respectively when compared to the control. Furthermore, improvements in FW, WG, SGR, and FCR were recorded for fish-fed supplemented diets with better values at T5. Moreover, liver enzyme activity, kidney function indices, and intestinal histomorphometric measurements were improved in fish-fed RO+AL treated diets. The recommended treatment is T5 (1 kg RO and 0.917 kg AL ton-1).