Red blood cell concentrations of reduced glutathione and potassium as biochemical markers of wool growth in Merino sheep

Wool growth rates were estimated in Merino ewes differing in their red blood cell concentrations of reduced glutathione ([GSH RBC ]). Over a 42-day wool growth period, sheep with low [GSH RBC ] maintained significantly higher rates of wool growth. Red blood cell concentrations of K + , ([K + RBC ]), [GSH RBC ] and estimated gene frequencies for the low [GSH RBC ] and high [K + RBC ] genes were determined in flocks of Merino ewes bred for high or low clean fleece weight. The high fleece weight flock had a significantly lower [GSH RBC ] and higher gene frequency for the low [GSH RBC ] allele than the low fleece weight flock. The high fleece weight flock also had a significantly higher [K + RBC ] and a higher gene frequency for the high [K + RBC ] allele than did the low fleece weight flock.