Curimbata, Prochilodus scrofa , were examined and selected for induced spawning with human chorionic gonadotropin (HCG). Intra-ovarian eggs were sampled and size composition was analyzed. With 21 females, two doses of HCG were applied at 10-h intervals, 5 IU and 10 IU per gram of total weight. According to response, three distinct groups were identified. For the groups where eggs were successfully fertilized, followed by embryonic development, the percent frequency distribution of egg diameter was unimodal with a constant mode of 1111.15 μm. It is suggested that for P. scrofa , selection of recipient females can be made on egg frequency-diameter distribution.