Effect of Crossbreeding of Two Nile Tilapia (Oreochromis niloticus) Strains, Chitralada 3 and Supreme, on Seed Production

Abstract

The purpose of this study was to study the seed production of crossbreeding Nile tilapia (Oreochromis niloticus) from the crossbreeding programmes between Chitralada 3 (CHI) and Supreme (SUP) strains. Four pairs of broodstock tilapia were bred: ♂CHI×♀CHI, ♂CHI × ♀SUP, ♂SUP × ♀CHI and ♂SUP × ♀SUP, respectively. Nile tilapia broodstock were reared at an average age of 1.5 years, 20 fish in each experimental group with male:female ratio of 1:1, each experimental group had 3 ponds for a period of 35 days. The eggs in the mouth of the tilapia mother were examined weekly. The results showed that all groups of female fish gave eggs at stage 1, 2, and 4 with average egg weight per unit between 0.0096-0.0100 g (P>.05). Pairs of the same species were ♂CHI × ♀CHI and ♂SUP × ♀SUP tended to have the number of spawning females per week, egg weight per female, and the average number of eggs per female was higher than the crossbreeding group ♂CHI × ♀SUP and ♂SUP × ♀CHI. It was found that pair of ♂CHI × ♀CHI had the number of female fish that spawned per week, the average egg weight per female, and the average number of eggs per female, which were significantly higher than other pairs (P<.05).