Table 3. Effects of age (AG) and weight (WT) of gilts at first mating on body weight and backfat thickness change during gestation and lactation over five consecutive parities

	AG (days)			WT (kg)			SEM	p-value
	< 220	220-240	241 ≤	< 140	140-149	150 ≤	SEM	AG	WT	AG × WT
Body weight gain during gestation (kg)
Parity 1	37.2^b	43.3^a	42.5^ab	45.8	44.0	40.6	2.17	0.046	0.069	0.216
Parity 2	33.4	32.9	32.8	32.7	32.4	34.0	2.00	0.999	0.869	0.900
Parity 3	28.8	29.6	27.1	26.1	28.9	29.3	1.62	0.133	0.095	0.545
Parity 4	29.2	30.4	28.2	28.1	30.2	28.6	1.68	0.358	0.482	0.862
Parity 5	29.6	29.7	27.9	28.7	28.4	30.1	1.70	0.858	0.424	0.649
Body weight loss during lactation (kg)
Parity 1	17.9	19.9	21.8	17.7	20.7	20.4	1.69	0.071	0.104	0.974
Parity 2	15.9	18.3	18.1	15.8	17.3	18.8	1.74	0.378	0.133	0.804
Parity 3	13.8	14.6	15.5	14.7	14.4	14.8	2.59	0.921	0.968	0.700
Parity 4	9.5	10.2	9.9	9.1	9.7	10.7	1.34	0.916	0.480	0.880
Parity 5	10.1	9.8	11.2	9.8	10.7	10.4	1.78	0.528	0.907	0.760
Backfat gain during gestation (mm)
Parity 1	2.51	3.39	2.99	2.63	2.81	3.32	0.32	0.059	0.091	0.965
Parity 2	1.90^b	2.61^a	2.39^ab	2.23^b	2.79	2.58	0.24	0.049	0.081	0.563
Parity 3	2.20^b	2.91^a	2.53^ab	2.43	2.89	2.63	0.25	0.047	0.109	0.101
Parity 4	2.70	2.92	2.40	2.56	2.71	2.66	0.28	0.568	0.851	0.103
Parity 5	2.28	2.29	3.74	2.28	2.24	4.98	1.96	0.819	0.232	0.895
Backfat loss during lactation (mm)
Parity 1	1.71^b	2.60^a	2.71^a	1.97^b	2.23^ab	2.82^a	0.26	< 0.01	0.021	0.703
Parity 2	1.42	2.40	2.33	1.81	2.48	2.44	0.29	0.102	0.083	0.792
Parity 3	1.73	2.19	1.97	1.78	1.83	2.25	0.65	0.670	0.793	0.952
Parity 4	1.47	1.77	1.60	1.46	1.66	1.64	0.111	0.849	0.872	0.941
Parity 5	1.67	1.71	2.84	2.03	1.63	3.84	1.96	0.885	0.402	0.785

Means (a,b) in column are significantly different (p < 0.01).