الفهرس 
REVIEW OF LITERATUREOnly 14 pages are availabe for public view
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Abstract
This experiment was carried out at Animal Production Laboratory, Animal Production Department, Faculty of Agriculture, Damietta University during the period from 21/10/2014 to 7/4/2015. Winter experiment started at 27/1/2015 as the amount of feed decreased to be 5 g/aquariam every 2 days. A total of 8 experimental aquariums were used in the present study, each with dimensions 70 cm length, 30 cm width and 50 cm height with capacity about 60 liters of water. Oxygen supply was through air compressor. Aquariams were cleaned twice weekly before partial replacing (75%) of water for removing the feces. The water source was chlorine-free tap water (stored water). The lighting period in lab was 12 hours. A total of 120 Nile tilapia (Oreochromis niloticus) fingerlings were obtained from special hatchery located in Faraskour – Damietta and divided into four groups (two replicates / treatment) and distributed onto the aquariams (15 fingerlings in each aquariam).
The study was run in many directions:
1- Evaluate the effect of different levels from Nigella sativa oil on growth performance and feed utilization during growing period.
2- Study the effect of Nigella sativa oil on fish resistance to the decrease in bodyweight during winter season.
3- Comparison of different nonlinear functions against linear model to describe the growth curve in Nile tilapia in order to select the best function.
The present results concluded that inclusion of Nigella sativa oil in Nile Tilapia (Oreochromis niloticus) diets improved growth performance and feed utilization relatively at 3 ml concentrate. For growth curve description under the effect of different treatments, Weibull and Morgan-Mercer-Flodin models were the best equations to describe growth curve in Nile tilapia followed by Von Bertalanffy and linear regression.