Effect of Density on Growth Hormone and Some Physiological Parameters and its Relation to Growth Performance
Gaber O. Moustafa, Asma S. Al‐Wasidi, mohamed wafeek, Haytham A. Abd El-Ghaffar, Ahmed M. Naglah, Atef Kalmouch, Mona Hamed
Abstract
The experiment was performed in the central laboratory for aquaculture research, Egypt. Experimental fish about 10.2 g Nile tilapia were divided into four different treatments in different ratios, and fed on 25% protein pellets for 120 days at 3% of body weight. Some parameters like some digestive enzymes (amylase and lipase), glucose, cortisol, insulin, growth hormone, iron and total binding iron capacity were measured in blood serum; the 4th treatment showed the minimum value for theses measurements except for glucose and cortisol 153.6±9.2 mg/dl and 176.3±5.2 ng/ml, respectively. Haemoglobin showed the highest and minimum value (7.63±0.03 g/dl & 6.27±0.03 g/dl) in treatments (1and 4) respectively. Erythrocytes count showed the highest value 2.52±0.01(X106/Cmm) in the first treatment, while the lowest value 2.09±0.03 (X106/Cmm) was recorded among treatment (4). Water samples for physico-chemical analysis were monitored bi-weekly during the study period then collected and tabulated in one mean. The growth performance of experimental fishes was significantly decreased with increasing fish density.