Modified granulocyte test for determination of mannosidosis genotype of cattle

Recovery of alpha-mannosidase, beta-N-acetylglucosaminidase and arylsulphatase activity from granulocytes is increased by inclusion of 154 mM sodium chloride, in place of 1 mM zinc chloride, in aqueous Triton X-100 used to extract the cells. Calculation of the ratio of alpha-mannosidase to beta-N-acetylglucosaminidase and to arylsulphatase permits diagnosis of the mannosidosis genotype without recourse to examination of smears of the granulocyte preparations.