Table 4. Effects of dietary energy and lysine levels on reproductive performance 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
Total born	13.1	16.0	13.5	9.6	12.4	8.2	13.0	12.8	3.10	0.17	0.53	< .01
Stillborn	1.0	0.8	0.0	0.4	0.4	0.6	0.7	0.3	0.78	0.90	0.72	0.50
Mummy	0.1	2.2	0.0	0.0	0.2	0.6	0.7	0.0	0.70	0.45	0.01	0.10
Born alive	12.0	13.0	13.5	9.2	11.8	7.0	11.6	12.5	3.10	0.29	0.40	0.04
Litter weight (kg)
Total litter weight	15.40	16.79	16.58	12.98	15.34	10.70	15.10	14.64	3.53	0.24	0.54	0.18
Alive litter weight	14.43	14.63	16.57	12.58	15.00	10.14	14.00	14.31	3.68	0.38	0.46	0.37
Alive piglet weight	1.23	1.13	1.22	1.37	1.29	1.51	1.22	1.16	0.17	0.35	0.79	0.02
Piglet uniformity on farrowing
SD	222.9	218.5	198.6	232.6	271.5	169.1	247.7	233.3	77.66	0.62	0.51	0.48
CV	19.0	19.5	16.4	17.6	21.7	13.2	20.5	21.1	6.95	0.65	0.64	0.36
Piglets < 800 g (%)	9.5	7.3	3.0	5.6	8.0	12.6	13.2	9.8	12.40	0.31	0.98	0.82
Piglets > 1,600 g (%)	12.8	2.0	1.5	19.0	11.8	34.4	9.8	4.5	15.51	0.32	0.60	0.08

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.