Camellia sinensis supplemented diet enhances the innate non-specific responses, haematological parameters and growth performance in Mugil cephalus against Photobacterium damselae.

This study evaluated the effect of dietary supplementation of Camellia sinensis leaf-extract on non-specific immune responses and disease resistance of Mugil cephalus fingerling against P. damselae. Fish were fed with 0 (unsupplemented), 50, 100 and 200 mg/kg of green tea extract (GTE) supplemented diets. Results indicated that GTE decreased mortality in M. cephalus in a dose-dependent manner after challenge with P. damselae. Haematological parameters containing RBC, Hct, Hb and WBC and growth performance (weight gain) showed remarkable changes in comparison with control group. In addition, the phagocytic (PA) and respiratory burst activity (RBA) significantly increased in M. cephalus, fed 100 and 50, 100 and 200 mg/kg GTE, respectively. Lysozyme statistically increased in GTE supplemented fish. Overall, our results indicated that incorporation of C. sinensis supplemented diet at 100 and 200 mg/kg doses significantly enhanced the immune responses in M. cephalus and that the mortality percentage could be remarkably reduced after challenging the fish against P. damselae.