Table 2.

Effects of a regular free acidifier or a micro-encapsulated combination of organic acids and essential oils on performance of weaned pigs pre- and post-challenged with enterotoxigenic Escherichia coli F4 (K88⁺).

Item	Treatments1					SEM2	P-value
	PC	NC	FA	P1	P2
BW at d 0, kg	7.42	7.41	7.41	7.42	7.41	0.06	0.99
Day 0 to 7
ADG, g	449	482	478	457	527	30.3	0.44
ADFI, g	697	710	725	666	772	36.7	0.41
G:F	0.65	0.68	0.67	0.69	0.68	0.03	0.86
Day 7 to 14
ADG, g	488	356	396	478	504	34.2	0.04
ADFI, g	800	623	713	710	799	42.5	0.05
G:F	0.61ab	0.56b	0.55b	0.68a	0.63ab	0.02	<0.01
Day 14 to 21
ADG, g	477ab	394b	421b	499ab	545a	31.8	0.02
ADFI, g	856	760	808	851	917	42.5	0.16
G:F	0.56	0.53	0.52	0.58	0.60	0.03	0.17
Day 7 to 21
ADG, g	483	390	424	486	521	27.1	0.08
ADFI, g	828	696	785	781	858	42.1	0.13
G:F	0.58	0.56	0.54	0.63	0.62	0.02	0.07
Day 0 to 21
ADG, g	471	421	446	476	512	39.9	0.40
ADFI, g	784	707	789	732	830	39.9	0.22
G:F	0.60	0.59	0.56	0.65	0.62	0.02	0.09

BW = body weight; ADG = average daily gain; ADFI = average daily feed intake; G:F = gain-to-feed ratio.

^a,b Different superscripts within a row indicate a significant difference (P < 0.05).

¹PC, non-challenged positive control; NC, enterotoxigenic Escherichia coli F4 (K88⁺)-challenged (on d 7) negative control; FA, NC + kitasamycin at 50 mg/kg + olaquindox at 100 mg/kg + regular free acids at 5 g/kg; P1, NC + kitasamycin at 50 mg/kg + olaquindox at 100 mg/kg + micro-encapsulated combination of organic acids and essential oils at 1 g/kg; P2, NC + kitasamycin at 50 mg/kg + olaquindox at 100 mg/kg + micro-encapsulated combination of organic acids and essential oils at 2 g/kg.

²SEM means standard error of the means (n = 6).