Study Ongrowth Models Of Gift Tilapia Pedigrees And Related Indicators Of Immunity

The study was aimed to study growth models of GIFT tilapia at different families, different genders under different farming environments as well as growth indicators related to immunity in tilapia. The six different pedigrees of GIFT male tilapia were selected and identified according to different families, different gender reared separately, and then different pedigrees and different gender were mixed to feed into the small ponds and aquaculture ponds, the experimental period was150days. At different time, intestinal digestive enzyme activities, liver and pancreas antioxidant capacity and immunological index were measured in GIFT tilapia, and the correlation between growth and immunity in the tilapia was observed.The results showed that Gompertz growth equation fit best for the growth of body length with residual sum of squares of0.55and R2is0.9949, followed by GD GF and VB GF equation; The quality fit for fish showed VB GF equation was the best, the residual sum of squares or R2is750.403or0.999respectively, inflection weight and maximum monthly weight gain was498.8g per month or16.33per week. The study indicated that the values of total antioxidant capacity and amylase activity decreased significantly at the seventh week and reached a peak at the fourteenth week, then the values gradually dropped. The high values of Peroxidase, catalase, xanthine oxidase and proteases were observed at the seventh week.The values gradually dropped from the seventh week and increased at fourteenth week. The spleen index decreased along with the increases of both body weight and age. The activities of alkaline phosphatase and total superoxide dismutase rose from the seventh week to the fourteenth week.