Nonetheless, three markers associated with body weight were found. The QTL for body weight was found in two experiments with fish in two different growth stages.
Fish in the second experiment were 3 months older and grew in better rearing conditions; therefore, they were at a more advanced stage of growth than in the first experiment (mean body weights of 10.4F5.9 and 67.8F41.4 g, respectively, for the first and second experiments) with similar high variation as reflected from the coefficient of variation of approximately
60%.
As the physiological windows are different in the two populations, the QTL effect is expected to vary in the two experiments.
This can be viewed in Table 3, where the QTL genotype effects were similar for BW but not for CDD between the two experiments.
Nevertheless, the significance of the QTL in both experiments confirms their involvement in these traits.
Associations between AFLP and microsatellite markers and body weight were also found in the same linkage group in a family of four-species tilapia hybrids (J. Agresti, T. Famula, G. Gall and B. May, University of California, Davis, unpublished results).