Table 8.

Effect of dietary treatment on carcass characteristics1

	Replicate		Diet				P
Parameter	Summer2	Spring3	A4	GLN5	NA6	SE	D7	R8	D x R
No HCW9 covariate
HCW, kg	92.42	97.44	95.32	95.54	93.93	1.32	0.60	<0.01	0.70
Loin depth, mm	63.95	67.46	65.79	65.85	65.48	0.72	0.93	<0.01	0.60
Backfat, mm	21.35	22.05	21.73	21.64	21.73	0.59	0.99	0.31	0.40
Yield, %	77.18	75.67	76.55	76.36	76.36	0.19	0.68	<0.01	0.46
Lean, %10	54.42	54.61	54.51	54.55	54.47	0.25	0.97	0.53	0.54
Fat-free lean, %11	48.69	48.79	48.74	48.79	48.69	0.30	0.97	0.76	0.50
HCW covariate
Loin depth, mm	64.43	66.99	65.72	65.74	65.68	0.69	0.99	0.01	0.66
Backfat, mm	22.02	21.41	21.64	21.49	22.00	0.49	0.75	0.33	0.57
Yield, %	77.33	75.52	76.52	76.33	76.42	0.17	0.69	0.01	0.63
Lean, %	54.20	54.82	54.54	54.60	54.38	0.23	0.78	0.04	0.71
Fat-free lean, %	48.41	49.06	48.77	48.85	48.58	0.27	0.77	0.07	0.68

¹A total of 10 pens were used per dietary treatment per replicate.

²Pigs weaned and transported for 12 h during July 2016.

³Pigs weaned and transported for 12 h during April 2017.

⁴Pigs provided dietary antibiotics [chlortetracycline (441 ppm) + tiamulin (38.6 ppm)] for 14 d postweaning and transport and then fed common antibiotic-free diets.

⁵Pigs provided 0.20% l-glutamine for 14 d postweaning and transport and then fed common antibiotic-free diets.

⁶Pigs provided no dietary antibiotics for 14 d postweaning and transport and then fed common antibiotic-free diets.

⁷Dietary treatment.

⁸Replicate.

⁹Hot carcass weight.

¹⁰Equation used: 54.672154 − (0.412525 × backfat, mm) − (0.002982 × hot carcass weight, kg × 2.20462) + (0.1433242 × loin depth, mm) (Indiana Packers Corporation, 2015).

¹¹Equation used: 51.2 - (0.510 × backfat, mm) + (0.131 × loin depth, mm) (Schinckel et al., 2010).