Table 5. Effects of dietary energy and lysine levels on growth of progeny in primiparous sows

Item1)	ME 3,265 kcal/kg				ME 3,365 kcal/kg				SEM	p-value
	Lys	Lys	Lys	Lys	Lys	Lys	Lys	Lys		E	L	I
	0.55	0.65	0.75	0.85	0.55	0.65	0.75	0.85
	0.70	0.85	1.00	1.15	0.70	0.85	1.00	1.15
	%	%	%	%	%	%	%	%
No. of piglets
After fostering	11.6	11.3	11.5	11.6	11.4	11.2	11.5	11.5	0.65	0.63	0.70	0.97
21 d of lactation	10.8	11.2	11.5	10.6	10.6	10.8	10.2	10.2	1.22	0.17	0.77	0.82
Litter weight (kg)
After fostering	13.95	12.65	13.84	15.56	14.42	15.84	14.26	13.69	1.625	0.36	0.90	0.04
Day 21 of lactation	54.16	55.75	61.02	56.44	58.41	60.18	58.12	54.95	9.687	0.74	0.83	0.79
Weight gain (0–21 d)	40.21	43.10	47.18	40.88	43.99	44.34	43.86	41.26	8.761	0.86	0.72	0.85
Piglet weight (kg)
After fostering	1.19	1.13	1.21	1.34	1.27	1.41	1.24	1.19	0.159	0.25	0.90	0.07
Day 21 of lactation	4.98	4.98	5.31	5.30	5.54	5.65	5.77	5.35	0.740	0.08	0.85	0.81
Weight gain (0–21 d)	3.79	3.85	4.10	3.96	4.27	4.24	4.53	4.16	0.626	0.08	0.73	0.96
Piglet uniformity on day 21 of lactation
SD	1,076	925	1,204	1,144	944	1,037	1,067	967	370.9	0.48	0.81	0.83
CV	21.8	19.9	22.7	22.0	17.1	18.6	18.8	18.6	7.83	0.19	0.97	0.96

Factors: energy level (3,265 or 3,365 kcal of ME/kg) and lysine level (total lysine 0.55/0.70%, 0.65/0.85%, 0.75/1.00%, 0.85/1.15%) in gestation/lactation diet.
ME, metabolizable energy; Lys, lysine; SEM, standard error of the mean; E, energy effect; L, lysine effect; I, interaction between energy and lysine effect; SD, standard deviation; CV, coefficient of variation.