The results were as follows: (l )The polymorphism of serum esterase was controlled by three alleies-ESF, ES1 and ESS and the ES1 gene was a preponderant allele (0. 500) in the Yushu horses examined.

• 结果表明： （1）被检玉树马血清酯酶的多态性受ESF，ES1和ESS 3个等位基因控制，以ES1为优势等位基因（0.；500）；