The rumen microbial metagenome associated with high methane production in cattle

BMC Genomics

Table 1 Estimation of abundance of 18S and 16S rRNA genes by qPCR in four pairs of steers with extreme methane emissions

	AA/Conc		L/Conc		AA/Med		L/Med		Mean		P value	Ratio (H/L)
	Low	High	Low	High	Low	High	Low	High	Low	High	P value	Ratio (H/L)
CH₄ (g/kg DM intake)	7.63	18.14	9.29	20.13	17.41	32.42	19.37	30.37	13.43	25.26		1.88
qPCR of 16S and 18S rRNA genes (copies/ng DNA)
Protozoa	9395	8315	464	18865	500	24480	20940	1768	7825	13357	0.613	1.71
Bacteria	923503	1026155	964081	572312	891432	575574	563798	595201	835704	692311	0.329	0.83
Archaea	23269	72076	21459	40242	19662	54880	37006	75912	25349	60777	0.011	2.40
Cluster IV	110080	278085	114411	76922	135520	221092	175738	236213	133937	203078	0.201	1.52
Cluster XIVa	193249	119584	173592	99130	181399	89060	97723	155352	161491	115782	0.279	0.72
Bacteroidetes	337544	276658	215824	299295	342174	134542	274886	122765	292607	208315	0.277	0.71
Proteobacteria	3341	^a	9783	1446	21270	2085	4350	2489	11801^a	2007^a	0.192	0.17

Comparison of methane emissions (g/kg DM intake) and the abundance of various bacterial taxa as determined by qPCR for 4 pairs of steers matched for breed and diet. AA Aberdeen Angus, L Limousin. Conc, high concentrate diet; Med, mixed forage: concentrate diet. DMI dry matter intake
^aSample produced an abnormal melt curve. The mean was based on the three other pairs

ISSN: 1471-2164