Abstract
Medicinal plants are the most utilized and validated feed additives in the aquaculture industry. This study investigated the dietary effects of anise (Pimpinella anisum L.) in European sea bass (Dicentrarchus labrax). Fish were treated with anise at 0, 1.5, 2.5, and 3.5 g per kg diet for successive 120 days. The results showed a marked enhancement in the growth performance and reduced feed conversion ratio in fish-fed anise compared to the control group (p < 0.05). The carcass composition showed that crude protein was meaningfully (p < 0.05) by 2.5 and 3.5 g anise per kg diet. The viscerosomatic index was significantly (p < 0.05) improved in the case of 3.5 g anise per kg diet. The intestinal antibacterial capacity showed a noticeably reduced count of Vibrio spp. and faecal coliform in the intestines of fish treated with 2.5 and 3.5 g anise per kg diet compared to the control (p < 0.05). Hematocrit and red blood cells (RBCs) showed higher levels in 2.5 and 3.5 g anise per kg diet groups than the control diet without significant differences with the 1.5 g/kg group (p > 0.05). In addition, the hemoglobin and white blood cell (WBCs) levels were significantly higher in anise treated groups than in the control group (p < 0.05). The immune response of European sea bass fed dietary anise showed that fish treated with 1.5 g anise per kg diet had higher lysozyme and phagocytic activities than the other groups (p < 0.05). In conclusion, incorporating anise into the diet of European sea bass is suggested to enhance performances and well-being.