Variability of Egg Characteristics among Female White Bass and the Relationship between Egg Volume and Length at Hatch of Sunshine Bass

Abstract

Domesticated white bass Morone chrysops can be used in selective breeding programs to produce sunshine bass (female white bass × male striped bass M. saxatilis). In addition to fast growth or favorable feed conversion, selection could be based on favorable egg or larval characteristics. Eggs from 12 white bass were fertilized with striped bass sperm to produce sunshine bass larvae and were individually photographed and incubated. The yolk sac larvae hatched from these eggs were also photographed within 3 h of hatching. Percent hatch ranged from 49% to 96%. Egg and larval characteristics were determined from the digital images. Total lipid and fatty acid composition were determined for eggs from each female. Average egg volume ranged from 0.32 to 0.42 mm³. Standard lengths of yolk sac larvae ranged from 2.51 to 3.62 mm. The relation between individual egg volumes and individual standard lengths explained only 1% of the variability in length at hatch. Average egg characteristics were generally unrelated to average length at hatch, but fatty acid composition was related to percent hatch. Maternal effects explained about 11% of the variability in individual length at hatch, and time to hatch (i.e., the length of time from fertilization to hatch for an individual embryo) explained 25% of the variability in individual length at hatch. Some females produced eggs and larvae with characteristics that were more suitable to increasing survival and fingerling production. Selection for these characteristics in broodstock white bass females could lead to improved production of sunshine bass fingerlings.