Table 3.

PRRS viremia and antibody titers of pigs fed high and low soybean meal diets or nitrogen-free diet during PRRSV infection

Parameter	Complete diet					P-value1			Nitrogen-free diet			P-value1
	HSBM−	HSBM+	LSBM−	LSBM+	SEM	Diet	dpi	Diet × dpi	Control	PRRS	SEM	Diet	dpi	Diet × dpi
PRRS viremia2
7 dpi	≥37	20.1	≥37	19.5	1.29	0.205	<0.001	0.567	≥37	19.3	0.91	<0.001	<0.001	<0.001
14 dpi	≥37	27.3	≥37	24.7					≥37	26.2	1.08
21 dpi	≥37	32.6	≥37	30.6					≥37	32.4	1.08
PRRSX3 antibody3
7 dpi	<0.40	0.97	<0.40	0.97	0.36	0.550	<0.001	0.400	<0.40	0.94	0.01	<0.001	<0.001	<0.001
14 dpi	<0.40	2.42	<0.40	2.27					<0.40	2.03	0.13
21 dpi	<0.40	2.04	<0.40	2.57					<0.40	2.17	0.13

HSBM−, LSBM− = high soybean meal (HSBM), low soybean meal (LSBM) without PRRS; HSBM+, LSBM+ = high soybean meal (HSBM), low soybean meal (LSBM) with PRRS; PRRSV = porcine reproductive and respiratory syndrome virus.

¹Main effect of diet, day post inoculation (dpi), and interaction of diet × dpi.

²Ct ≥ 37 denotes negative PRRS outcome.

³PRRSX3 antibody S/P ratio < 0.40 denotes PRRS negative.