Physiological and immunological impact of methanolic lavender extract on female goldfish (Carassius auratus)

The integration of herbal medicine into the ornamental fish industry carries the potential to exert an impact on the overall health and welfare of the fish. In the present study, different levels of lavender extract (L), including control (L0) 1.5 (L1.5), 3 (L3), and 4.5 (L4.5) mg kg− 1 feed were examined in goldfish (Carrasius auratus) broodstock during 56-day feeding period following air exposure stress test. Growth parameters, cortisol, biochemical, and immunological parameters in blood and mucus and. reproductive performance were examined. Notably, fish in the L3 group showed significant (p <0.05) improvement in growth performance, as evidenced by significant increases in weight gain, specific growth rate, and average daily growth. After stress, fish in the L3 group showed the lowest cortisol and glucose levels in plasma and skin mucus (p < 0.05). Cholesterol and triglyceride
levels showed a significant increase in the L3 group compared to other groups (p < 0.05). Fish in L3
showed a significant increase (p < 0.05) in plasma and Complementary 3 and Immunoglobulin M The reproductive results indicated that broodstock in the group obtained a high fertilization rate, hatching rate, and larval survival (p <0.05). This study indicated that 3 mg kg− 1 lavender extract can promote fish performance, mitigate stress responses, improve immunity function and ameliorate reproductive performance; thus, lavender supplementation can be recommended as a practical method in the ornamental fish industry.