Table 5. Effects of interaction between loading density and air temperature on carcass composition and carcass grade during pre-slaughter pig transport

Variable	LT			NT			HT			SEM	p-value
Variable	LD	ND	HD	LD	ND	HD	LD	ND	HD	SEM	Treatments	Interaction
N	659	921	576	291	647	258	123	169	259	-	-	-
Carcass composition traits
Hot carcass weight (kg)	85.82^ab	86.26^a	85.30^abc	83.30^d	84.08^cd	84.58^bcd	83.81^d	83.30^d	84.21^cd	0.09	< 0.001	0.072
Backfat thickness (mm)	20.29^a	20.03^ab	20.17^ab	17.98^d	18.38^cd	18.68^cd	19.26^abc	19.18^bc	19.35^abc	0.07	< 0.001	0.318
Backfat thickness hot carcass weight ratio (mm/kg)	0.236^a	0.232^a	0.236^a	0.216^d	0.218^cd	0.220^bcd	0.229^abc	0.230^ab	0.229^abc	0.001	< 0.001	0.323
Carcass grade
Grade 1+ (%)	43.4	38.8	38.5	39.9	41.3	36.8	28.5	29.6	37.4	-	-	-
Grade 1 (%)	35.4	38.8	37.7	33.3	33.4	29.1	34.1	30.2	26.3	-	-	-
Grade 2 (%)	21.2	22.4	23.8	26.8	25.3	34.1	37.4	40.2	36.3	-	-	-
Carcass grade score¹⁾	2.220^a	2.163^ab	2.148^ab	2.131^ab	2.156^ab	2.054^abc	1.911^c	1.894^c	2.012^bc	0.013	< 0.001	0.124
Pig losses
Fracture (n)	1	0	1	0	1	0	2	0	0	-	-	-
Bruiser (n)	0	0	0	2	0	0	0	0	1	-	-	-

Carcass grade score was determined as follows: 3, grade 1+; 2, grade 1; 1, grade 2.
Means in the same row with different superscripts differ (p < 0.05).
LT, low air temperature (lower than 10°C); NT, normal temperature (10°C to 24°C); HT, high temperature (higher than 24°C); LD, low density (lower than 0.43 m²/100 kg); ND, normal density (0.37 m²/100 kg to 0.43 m²/100 kg); HD, high density (higher than 0.37 m²/100 kg).