Performance evaluation of Nile tilapia (Oreochromis niloticus) improved strains in Ghana

Abstract Growth performance and survival to harvest of the Akosombo strain generation 10 and the GIFT strain generation two (derived from GIFT generation 11 in Malaysia) were evaluated in Ghana. The fish were from 97 families of the Akosombo selected line (AKOS), 30 of the Akosombo control line (AKOC), and 24 of the GIFT strain (GIFT). In total, 12,043 tagged fingerlings were stocked at a density of 3 fish.m−2 into two ponds, each 2000 m2. Fish were fed 38% crude protein pelleted feed, twice daily at a rate of 5% body weight, for 120 days. Harvest weight of GIFT (150.1 ± 58.5 g) was 2.2 times larger than AKOC (67.6 ± 28.4 g) and 1.8 times larger than the AKOS (85.2 ± 32.0 g) strains. The least-squares mean weight of male GIFT were 98.6 g more than AKOC and 82.7 g more than AKOS. The corresponding ratios for females were even greater, with female GIFT weighing 106.5 g more than AKOC, and 89.9 g more than AKOS. The AKOS grew larger than the AKOC, 15.9 g larger for males and 16.6 g for females. All differences were highly significant (P