Carcass weight, backfat thickness and
NPPC marbling score
The carcass weight of the pigs was influenced by
weaning age and weight (P < 0.01). The L group in
D21 had significantly higher carcass weight than that
from the M and H group (P < 0.05) (Table 3).
However, in D28, no significant difference was seen
among the weaning weight groups (P > 0.05). The D28
pigs also had higher carcass weight than did the D21
pigs (P < 0.01). These results show that light piglets
grow faster than medium or heavy piglets, regardless
of weaning age, and weaning at 28 days increases the
carcass weight of pigs. In the previous reports, piglets
weaned at 42 days were better able to adapt to
weaning than were younger piglets, as a result of them
having a more developed digestive system (Hay et al.
2001; Jarvis et al. 2008). Wean-to-finish growth performance,
including ADG, mortality and weight,
improved as weaning age increased from 12 days to 21
days (Fangman et al. 1996; Main et al. 2004). In the
present study, older piglets at weaning showed higher
carcass weight than did younger piglets, but the piglets
of L in D28, which had the slowest growth rate until
weaning, showed the highest carcass weight. Other
studies reported that backfat thickness and intramuscular
fat content increased with an increase in carcass
weight (Galián et al. 2009; Kim et al. 2013). However,
in the present study, the pigs that had higher carcass