The aim of this study was to examine the growth potential of indigenous pig breeds Mangalitsa (swallow bellied; n=12) and Moravka (n=10). The investigation included male castrates (surgical). Pigs were transferred from different farms to the institute’s stable where pigs were housed. The fattening period started at an average weight of 24.3 kg and 173.1 days of age for Mangalitsa pigs and 29.9 and 170.8 days for Moravka pigs, respectively and finished at average weight of 115.5 kg and 357 days of age for Mangalitsa pigs and 131.3 kg and 363 days for Moravka pigs, respectively. During observation study Moravka pigs had 13% higher (but not significantly) growth rate than Mangalitsa breed (545 vs. 480 g/day, P=0.22). The maximal growth rate observed for Mangalitsa was 690 g and for Moravka 607 g in the period corresponding to average body weight (end of period) of 79 and 89 kg, respectively. Initial (at start of the study) difference in growth rate between Mangalitsa and Moravka was propagated along the study duration resulting in significant difference in body weight at slaughter (P < 0.05).