Temporal microbial colonization on different forages is driven by the rumen environmental conditions

Table 2 Ruminal volatile fatty acids variations in the different rumen environmental conditions after feeding

Time	AHR¹							CSR¹							SEM	P value²
Time	0	0.5	2	4	8	16	24	0	0.5	2	4	8	16	24		R	T	R × T
Total VFA, mM/L	116^abc	127^a	107^bc	126^ab	100^c	117^abc	116^abc	90^b	105^a	85^bc	83^bc	80^bc	76^c	90^b	3.07	< 0.01	< 0.01	< 0.01
Molar proportion, mM/100 mM
Acetate	66.6^ab	67.1^a	66.4^ab	65.8^b	63.8^c	63.4^c	66.6^ab	70.5^a	70.4^a	68.3^b	67.3^b	68.0^b	67.7^b	70.5^a	0.24	< 0.01	< 0.01	< 0.01
Propionate	17.7^c	18.7^bc	18.5^bc	19.7^ab	18.7^bc	21.1^a	17.7^c	15.9^d	15.5^d	20.1^ab	21.1^a	18.4^c	19.0^bc	15.9^d	0.29	< 0.01	< 0.01	< 0.01
Butyrate	11.4^b	10.9^b	12.1^ab	11.5^b	13.6^a	12.5^ab	11.4^b	10.9^b	11.8^a	8.9^d	9.2^d	10.3^c	10.4^bc	10.9^b	0.24	< 0.01	< 0.01	< 0.01
Isobutyrate	1.3^a	0.8^b	0.8^b	0.8^b	1.2^a	0.8^b	1.3^a	0.9^bc	0.7^d	0.8^bcd	0.8^cd	1.1^a	1.0^ab	0.9^bc	0.04	< 0.01	< 0.01	< 0.01
Valerate	1.5^a	1.4^a	1.3^a	1.5^a	1.4^a	1.4^a	1.5^a	0.7^b	0.7^b	0.8^b	0.8^b	0.9^a	0.8^ab	0.7^b	0.04	< 0.01	0.15	< 0.01
Isovalerate	1.5^a	1.0^bc	1.0^c	0.8^c	1.4^ab	0.7^c	1.5^a	1.2^ab	0.9^c	1.2^b	0.9^c	1.2^a	1.1^bc	1.2^ab	0.05	< 0.01	< 0.01	< 0.01
Acetate/Propionate	3.76^a	3.59^ab	3.60^ab	3.34^b	3.44^b	3.01^c	3.76^a	4.44^a	4.55^a	3.41^bc	3.19^c	3.69^b	3.57^b	4.44^a	0.07	< 0.01	< 0.01	< 0.01

^a⁻^dMeans within the same column with different superscripts are significantly different (P < 0.05)
¹AHR: alfalfa hay rumen environmental condition; CSR: corn stover rumen environmental condition
²R = treatment effect, T = time effect, F × T = interactive effect of treatment and time

ISSN: 2524-4671