Divergent Selection for Body Weight and Yolk Precursor in Coturnix coturnix japonica

Abstract

From a randombred control population of Coturnix coturnix japonica, four strains were selected respectively for high and low 4-week body weight and high and low total plasma phosphorus (plasma yolk precursor). Based on seven generations of selection, die realized heritabilities plus or minus their standard errors for high and low body weight strains were .37 ± .05 and .44 ± .28, respectively. The total gain and gain per generation were greatest in the low weight strain, primarily due to greater selection differentials. Selection for plasma yolk precursor was more effective in the high than low strain. The respective realized heritabilities plus or minus standard errors were .32 ± .02 and .34 ± .03. The selection differentials were larger in the high strain than in die low strain. There was no significant change in plasma yolk precursor in the weight strains nor in 4-week body weight in die plasma yolk precursor strains, which indicated that the genetic correlation between body weight during the growing period and plasma yolk precursor during the laying period was close to zero.