| Abstract: | By means of starch gel electrophoresis blood plasma esterases in sheep of different breeds were studied. It is shown that the esterase pattern is a poly-enzyme system consisting of at least three enzymes: arylesterase, carboxylesterase and choline esterase. Postnatal changes of esterase pattern in sheep blood plasma were also studied. Polymorphism on substrate specificities is described, which is expressed in the fact that different arylesterase variants have different affinity to alpha- and beta-isomers of carbone ethers of naphtol. The breeding test suggests that two allelic autosomal genes, reffered to as Es-1a and Es-1b, control the substrate specificity of arylesterase in sheep. The data are discussed in connection with Es-1a and Es-1b gene expression in heterozygous sheep, with the effect of (mosaic) dominance. |
