Effect of fortified feed with olive leaves extract on the haematological and biochemical parameters of Oreochromis niloticus (Nile tilapia)

Olive leaves have been used traditionally to improve the immunity against several infections. Current study aimed to examine the effect of fortified feed with olive leaves extract on haematological and biochemical parameters of Oreochromis niloticus. Total 400 healthy fish were divided randomly into four groups and were cultured for two months in glass tanks of 250 L water capacity in triplicate. Fortified feed was prepared with various extract, 1%, 1.5% and 2% concentration in diet, while, control-group diet was without extraction. Results showed that all the haematological parameters including WBC, RBC, Hb, PCV and plasma protein were significantly increased while the biochemical parameters such as globulin albumen ratio increased in fish which fed on 1% of extract, but the level of cholesterol and triglycerides was decreasing by increasing the concentration of extract. It was concluded that olive leaves extract can be used to enhance the immunity, growth and health of fish.