Nitric Oxide is produced by macrophage when activated or invaded by certain antigens or microbes. In the present study, camel peripheral blood leukocytes were obtained by ficoll cushion. Monocytes were separated and grown to macrophages. The mature macrophages were exposed to E. coli LPS as well as sheep pox virus antigen. Nitric oxide Conclusively, results obtained in this study indicate that nitric oxide and nitrogenous compound intermediates are produced by activated camel macrophages like macrophages of other animal species. This supports, to a considerable limit, the stability of the microbicidal armatures in different animal species. However, further studies are required to detect production of other armatures such as the active oxygen radicals by camel macrophages. Moreover, the iNOS mRNA was found to be conserved among the species studied so far including camel.