Selective Breeding Technic Of Tilapia

Problems of tilapia aquaculture such as decreased growth, reduced resistivity, seriously disease and so on have emerged as the central issuses in our country. In order to alleviate the urgent badly situation studies of tilapia selective breeding should be one of important focus of the solutions. In this paper, better strains of Nile tilapia (Oreochromis niloticus) and Blue tilapia (Oreochromis aureus) with improved growth, low temperature or disease resistance were obtained by mass selection method, through 3 generations selection. Pure strains of Nile and Blue tilapia, and their cross strains were established. Then 4 strains with better characters were selected by family selection method. Growth compare was also carried out in the selected populations. Growth of populationâ… was 13.6% higher than populationâ…¡in Nile tilapia.15.7% of growth improvement was found in F2 progeny compared to unselected base population. All of the above shows the remarkable goodness dues to selected breeding job, however, we should recognize that continued the selected breeding job brings tremendous significance.The genetic variations among male and female blue tilapia genome DNA were evaluated by randomly amplified polymorphic DNA (RAPD). Among more than 600 random primers,2 primers were screened out which could stably demonstrate different polymorphism between male and female blue tilapia. We considered these two DNA makers were sexual related makers in blue tilapia. Meanwhile, marker 71699 was successfully transformed into SCAR marker, and we got its DNA sequence. Based on this marker, we formed a sex distinguish method by PCR in blue tilapia.