INCIDENCE OF UMP SYNTHASE DEFICIENCY IN SOUTH-AFRICAN HOLSTEIN CATTLE

Deficiency of uridine monophosphate synthase (DUMPS) is an inherited, recessive metabolic defect identified in Holstein cattle. Since hetero zygous carriers transmit the defective gene 50% of the time, one fourt h of the offspring from matings between two carriers are expected to b e homozygous for DUMPS. This is a lethal condition where embryos die e arly in gestation. Offspring produced from the imported semen of an Am erican carrier bull showed a carrier frequency of 54%. Among 277 South African Al bulls active during 1991 and 1992, no incidence was observ ed.