Table 2.

Effects of RFI line and hygiene conditions on redox status in plasma of pigs

Line	Low RFI		High RFI			P values
Hygiene	Good	Poor	Good	Poor	MSE	Line	Hygiene	LxH
Week 6 (n = 71)
dROM	987ab	1023b	857a	1200c	233	0.68	0.001	0.008
FRAP	203	192	210	185	22	0.95	0.002	0.18
Week 13–14 (n = 35)
dROM	1146	990	1045	1102	194	0.94	0.50	0.14
FRAP	202	232	202	207	30	0.71	0.31	0.11

Pigs from two lines divergently selected for low (LRFI) or high (HRFI) residual feed intake (RFI = were housed either in good or poor hygiene conditions during the first 6 weeks after their transfer in growing-finishing pens (period 1). Half of these pigs were killed at week 6, whereas another half were placed in good hygiene conditions until slaughter at weeks 13 or 14 (period 2). Blood was sampled from the jugular in living pigs at the end points of the two periods. Systemic reactive oxygen metabolites (dROM) were expressed as Carratelli Unit (1 CARRU = 0.08 mg H₂O₂/100 mL). Ferric reducing ability of plasma (FRAP), a measure of its antioxidant power, was expressed as molar Trolox equivalents per L. Letters (a,b,c) were added in case of interaction (LxH; P < 0.10) between hygiene (H) and RFI line (L), and means sharing a common letter did not differ. MSE: root mean standard error of the statistical model. Bold face highlights significant differences (P ≤ 0.05) between treatments