Susceptibility of dairy cows to subacute ruminal acidosis is reflected in both prepartum and postpartum bacteria as well as odd- and branched-chain fatty acids in feces

Table 4 Average relative abundance (%) of bacterial groups in feces sampled on d 21 postpartum that differ among groups of dairy cows varying in SARA susceptibility over the first 3 postpartum weeks¹

Phylum	Family	Genus	SU²	MS²	MU²	UN²	SEM³	P_adj⁴
Firmicutes			71.6	76.7	72.3	75.4	1.27	0.127
	Streptococcaceae		0.035^a	0.002^b	0.010^b	0.022^b	0.0032	0.022
		Streptococcus	0.035^a	0.002^b	0.010^b	0.018^b	0.0029	< 0.001
	Ruminococcaceae	Ruminococcus	2.14^a	2.33^a	2.15^a	1.53^b	0.154	0.008
		Anaerosporobacter	0.037^a	0.018^a	0.027^a	0.000^b	0.0082	< 0.001
	Erysipelatoclostridiaceae	Candidatus_Stoquefichus	0.313^a	0.103^b	0.198^b	0.231^a	0.0431	< 0.001
	Clostridia_UCG-014	Clostridia_UCG-014	1.45^b	2.83^a	1.34^b	1.34^b	0.143	< 0.001
Bacteroidota			23.2	16.5	22.7	20.0	1.37	0.338
	Prevotellaceae	UCG-001	0.516^a	0.300^ab	0.421^ab	0.279^b	0.0403	< 0.001
Proteobacteria			0.466	1.13	1.29	0.592	0.1812	0.971
Actinobacteria			1.47	1.42	1.22	0.74	0.261	0.971
Patescibacteria			1.43	2.09	1.23	1.74	0.188	0.606
Spirochaetota			0.859	1.06	0.552	0.856	0.1216	0.971

¹Only differentially abundant taxa with relative abundance ≥0.01% are included here. Phyla with a relative abundance ≥1% are also presented here, even if they did not differ among groups
²Postpartum grouping: susceptible group (SU; n = 10): mean or median of time below pH 6 of at least 180 min/d; moderately susceptible group (MS; n = 7): 60 min/d < mean time of pH below 6 < 180 min/d and median time of pH below 6 < 180 min/d; moderately unsusceptible group (MU; n = 11): 10 min/d < mean time of pH below 6 < 60 min/d and median time of pH below 6 ≤ 30 min/d; unsusceptible group (UN; n = 10): median time pH below 6 = 0 min/d and mean time pH below 6 < 10 min/d. Due to early calving, 10 cows were from the SU group, the UN-group only contained nine animals in the prepartum period and MS (n = 3) and MU (n = 7) cows were merged into a single group (MO, n = 10)
³SEM = standard error of the mean
⁴P_adj = P value adjusted for false discovery rate at 5%
^a,bMeans within a row with different superscripts differ significantly (P ≤ 0.05)

ISSN: 2049-1891