Effect of Stocking Density and Protein level on Behaviour, Survival, Growth rate, Crowding Status, Stress Response, Food Consumption Protein efficiency, and Body Composition of Hybrid (Oreochromis mossambicus × Oreochromis niloticus) in Saline Environment

Abstract

The present study was carried out at the Center of Excellence in Marine Biology University of Karachi over the period of 92 days to assess optimal salinity, effect of stocking density and two dietary protein level 30% (P1) and 40%(P2) crude protein on growth, survival rate feed conversion, body composition and production of Hybrid (Oreochromis mossambicus × Oreochromis niloticus). In present study, a 12 week trial conducted, 5, 10, 20, 40 (D1, D2, D3, D4/ P1 and D1, D2, D3, D4 /P2 respectively) fish/ 40L aquarium were stocked with two dietary protein level 30% (P1) and 40% (P2)CP on growth and feed utilization. The results were presented that growth of hybrid tilapia was significantly (P<0.05) condensed at P2 and high stocking densities (D3 and D4). Blood hemoglobin, RBC, WBC and %Hct were significantly different. Significantly (P<0.05) higher hematocrit concentration was observed at lower stocking densities indicating better physiological adaptation The resultant higher cortisol, blood sugar lactate and plasma protein levels at high stocking density were produced stress full condition. The physical parameters were at satisfactory level in all treatments.