The present study was conducted to establish baseline profiles of various macrophage functions in three commonly used laboratory animals viz., rabbits, guinea pigs and rats. All experiments were carried out between 4 to 6 weeks of age. Total number of peritoneal exudate cells per animal collected after a single intraperitoneal injection of Bacillus-Calmeue Guerin (BCG) were comparable among all these three animal species. Rabbits produced fewer macrophages along with reduced phagocytosis of opsonised and unopsonised sheep red blood cells (SRBC). Macrophages from guinea pigs and rats killed more opsonised Escherichia coli than rabbits. This study demonstrates species variation among the three laboratory animals for mononuclear phagocytic system functions.
