Utilization of Some Med Oreochromis Niloticus ical Plants as Feed Additives for Nile Tilapia, Oreochromis Niloticus, Feeds

There is an interesting in using of medical and aromatic plants or spices as feed additives in fish diets instead of chemical products to avoid side effects and achieve organic aquaculture. Feeding experiment was conduced to evaluate the growth of Nile tilapia fingerlings fed nine diets containing different levels (0, 0.5 or 1%) of dried marjoram leaves (DML), caraway seed meal (CSM), chamomile flowers meal (CFM) and fennel seed meal (FSM) as feed additives. A total number of 270 Nile tilapia fingerlings with an average initial weight (2.5g/fish) were randomly distributed into 27 glass aquaria (70L), in triplicate. Results indicated significant (P<0.05) differences in the final body weight, weight gain, specific growth rate (SGR), feed conversion ratio (FCR), protein efficiency ratio (PER) and protein productive value (PPV%) between fish fed diets containing (0.5 or 1%) of all tested feed additives and the control diet. Fish that fed diets contained 1% level of DML, CSM, CFM and FSM were superior in growth, feed conversion ratio and protein efficiency as compared to those fed 0.5% level. The proximate composition of whole fish body showed that no significant differences (P>0.05) among all fish groups fed experimental and control diets. It was concluded that, diet containing 1% CSM was economically superior to other tested diets. It saved about 21% of feeding cost per unit fish.