Table 3.

Rumen pH, volatile fatty acid (VFA) profiles and ammonia-N concentration after 6 h in vitro incubation

Item	Sucrose level				SEM1	P-value2
	0	3 %	6 %	9 %		T	L	Q
Rumen pH	6.17	6.17	6.18	6.19	0.014	0.971	0.641	1.000
Total VFA, mmol/L	73.8	74.8	75.9	76.5	0.391	0.056	0.009	0.738
Individual VFA (mol/100 mol)
Acetate	63.0a	62.8b	62.7b	63.1a	0.044	0.003	0.380	<0.001
Propionate	20.4a	20.1b	19.9bc	19.7c	0.074	0.001	<0.001	0.324
Butyrate	12.2c	12.7b	13.1a	12.9ab	0.090	<0.001	<0.001	<0.001
Isobutyrate	1.16a	1.14b	1.11c	1.08d	0.009	<0.001	<0.001	0.715
Valerate	1.25b	1.29ab	1.30a	1.31a	0.008	0.015	0.002	0.457
Isovalerate	2.07a	2.01b	1.95c	1.89d	0.018	<0.001	<0.001	0.804
A:P ratio3	3.09c	3.12bc	3.16ab	3.19a	0.012	0.002	<0.001	0.987
Ammonia, mg/dL	28.9a	27.5b	26.8b	26.6b	0.291	0.005	<0.001	0.114

Note: Means within the same row with different superscripts differ significantly (P < 0.05)

¹ SEM = standard error of mean

² Probability of a significant effect of treatment (T), or linear (L) and quadratic (Q) orthogonal contrasts for dietary sucrose levels

³ A:P ratio = acetate to propionate ratio