A phenotypically normal pregnant (2 months) Egyptian cow (Baladi breed) was examined cytogenetically among 10 other cows screened for any cytogenetic abnormality during an epidemic of lumpy skin disease. Cytogenetic analysis revealed a diploid/tetraploid mosaicism in only the case reported cow.  Two cultures were performed with a month interval in between. The first culture revealed a polyploid in 43% of the cells, while the second culture showed only 36% of cells to be polyploid. Blood counts done at the time of the first culture revealed mild lymphocytosis and monocytosis and many lymphocytes showed double nuclei.  Two other cultures done after a 10 months period from the second culture showed a normal karytoype.  Moreover the cytogenetical analysis of the newborn calf of this cow showed a normal  karytoype constitution. Most probably the lumpy skin virus "Neethling pox virus" was the cause of these temporary cytogenetic abnormalities.