The aim of the study was to investigate the development of haematological indices in the MeLiM strain of miniature pigs. MeLiM minipigs in group M were affected with hereditary malignant melanoma and received 100 mg Fe 3+ dextran i.m. on day 3 of age. Group H contained melanomafree MeLiM minipigs that were supplemented with iron as in group M. Melanoma-free MeLiM minipigs without iron supplementation till the week 5 of age were included in group A. Development of haematological indices in group H was compared to literature data from other breeds and strains of minipigs. Red blood cell indices in group A were found to be characteristic for hypochromic microcytary anaemia. Higher red blood cell counts were found in animals affected with melanoma (group M) on week 8 of age compared to group H. Pigs in group M showed also lower growth intensity compared to healthy animals (group H).Hereditary melanoma, MeLiM, haemoglobin, packed cell volume, iron