Table 3.

Ruminal fermentation characteristics following a 48-h in vitro incubation of forages using strained rumen fluid

Item	Chungcheong, central region				Jeolla, southern region				SEM	p-value
	Corn silage	IRG	Sudan-grass	Rice straw	Corn silage	IRG	Sudan-grass	Rice straw		Region	Forage	Region ×forage
pH	6.29d	6.42b	6.44b	6.54a	6.35c	6.45b	6.50a	6.51a	0.009	<0.01	<0.01	<0.01
NDFD (g/kg)	560ab	577a	408b	236c	466ab	600a	343bc	374bc	31.7	0.977	<0.01	<0.01
NH3-N (mg/dL)	15.0cd	23.0a	13.3d	17.4b	16.0bc	21.1a	16.5bc	15.4bcd	0.49	0.839	<0.01	<0.01
VFA (mM)	60.9a	55.4b	50.5c	39.3f	59.4a	54.7b	46.0d	42.3e	0.61	0.050	<0.01	<0.01
Acetate (mmol/mol)	624e	667c	709a	701a	644d	663c	676b	706a	1.8	0.047	<0.01	<0.01
Propionate (mmol/mol)	263a	220c	196d	188e	237b	224c	218c	193de	1.3	0.143	<0.01	<0.01
Butyrate (mmol/mol)	85b	77c	79c	71d	92a	69d	77c	72d	0.6	0.237	<0.01	<0.01
A/P ratio	2.4e	3.0bc	3.6a	3.7a	2.7d	3.0c	3.1b	3.7a	0.02	<0.01	<0.01	<0.01

IRG, Italian ryegrass; SEM, standard error of the mean; NDFD, Neutral detergent fiber digestibility; VFA, Volatile fatty acid; A/P ratio, Acetate to propionate ratio.

^a–fMeans in the same row that do not have common superscript differ significantly (p<0.05).