Performance of Krškopolje Pigs in Extensive and Intensive Production Systems

An observational study of growth performance was performed with Krškopolje pigs reared in extensive (EXT) and intensive (INT) production system. Pigs in INT system (n=6) were housed indoors and received a complete feed mixture, while EXT pigs (n=6) were kept in combined indoor/outdoor system and were fed a traditional meal (cooked root crops) and a mixture of ground grains. Growth performance and meat quality traits of longissimus dorsi (LD) muscle of pigs were assessed. Pigs were monitored from 86 to 224 days of age and were weighed 4-times (at 86, 129, 195, 224 days) with 4 growth stages (25-45, 45-75, 75-90 and 90-120 kg) considered. Overall INT pigs achieved 49 % higher daily gain and were heavier at slaughter than EXT pigs (88 vs. 120 kg, P<0.001). Growth rate of INT and EXT pigs was similar (443 vs. 464 g/ day) from 25-45 kg, whereas EXT pigs grew slower than INT pigs in the periods 45- 75 and 75-90 kg (445 vs. 853 and 505 vs 893 g/day, respectively). In the last period (90- 120 kg) only INT pigs were monitored and they exhibited a decline in growth rate (580 g/day) compared to the previous two periods. Due to higher body weight (BW) at slaughter, INT had thicker backfat than EXT pigs (40 vs. 22 mm, P<0.000), however at equal BW (88 kg), no differences were noted. EXT pigs exhibited lower CIE L* (P=0.044) and higher CIE a* (P=0.003) colour parameters of LD (i.e. darker, redder LD colour), indicative of more oxidative muscle metabolism of EXT pigs.