Effect of cinnamon (Cinnamomum verum) extracts on the growth and protection ability of tilapia (Oreochromis spp.) against Streptococcus agalactiae

Abstract

This study was conducted to investigate the effect of cinnamon (Cinnamomum verum) extract mixed to feed on growth parametersand the ability to protect tilapia against Streptococcus agalactiae isolated from infected tilapia (Oreochromis spp.) in Cu Chi district, Ho Chi Minh city. Cinnamon extract was mixed to feed with doses of 10, 20, and 40 g/kg feed. Fish were intraperitoneally injected with 0.1 ml of 1.8x104 CFU/ml of S. agalactiae. The negative control was injected with 0.1 ml of physiological saline. The results showed that the cinnamon extract (C. verum) mixed at the three above levels was shown to be safe for the growth and survival rate of tilapia. Moreover, cinnamon extracts well mixed at 20 g/kg feed proved the highest protection (with the relative percent survival (RPS) value being 51.4%). The cinnamon extract can be considered a potential herbal extract for the prevention of disease caused by S. agalactiae in tilapia.