Title: Variation of egg size of domestic white bass moreone chrysops due to dietary differences Authors
Submitted to: Book of Abstracts Aquaculture America
Publication Type: Abstract Only
Publication Acceptance Date: August 1, 2008
Publication Date: February 15, 2009
Citation: Mcentire, M.E., Fuller, S.A. 2009. Variation of egg size of domestic white bass moreone chrysops due to dietary differences [absdtract]. Book of Abstracts Aquaculture America. p.219. Technical Abstract: Tagged domestic three year old white bass brood fish were stocked in 5500 L tanks at the Harry K. Dupree Stuttgart National Aquaculture Research Center with flow through well water mimicking a normal thermal and diurnal pattern in the South Eastern USA. There were two groups of fish fed different diets during most of vitellogenesis. The control group was fed a 45 percent protein 16 percent fat diet containing primarily fish meal and the other was fed a 45 percent protein, 15 percent fat diet containing fish meal and squid meal. Fish were of the same age and genetic stock but held at different facilities prior to stocking. The mean (+ S.E.) fish weights were 714+121g for the control group and 558+105g for group fed the diet containing squid meal and were statistically different (p< 0.0001). In April fish were injected with a slow release gonadotropin-releasing hormone (GnRH) pellet to induce oocyte maturation and ovulation. Eggs were collected from 54 white bass females and preserved in 70 percent isopropyl alcohol. All the egg samples were treated the same and the amount of shrinkage in egg size was expected to be uniform and constant across groups. The eggs were later photographed and mean relative egg size was measured to the nearest mm (n=30). The mean egg diameter was 0.85+0.05mm for the control and 0.86+0.06mm for the diet containing squid meal. There was no statistical difference in egg sizes between the groups (p<0.5379). In addition egg diameter was not correlated with fish weight. However, egg size among the different individuals were statistical distinct, probably due to a genetic component. Future research should be directed towards egg size along with fertilization rate, percent hatch, and egg quality parameters such as lipid composition as it relates to the genetic origin of the fish.