Rumen microbiome structure and metabolites activity in dairy cows with clinical and subclinical mastitis

Table 1 Milk yield, compositions and rumen fermentation parameters in cows with different udder health status

Items	Experimental treatments			SEM	P-value
Items	H (n = 20)	SM (n = 20)	CM (n = 20)	SEM	P-value
Lactation parameters
Milk yield, kg/d	42.6^a	32.7^b	28.5^b	1.43	< 0.010
Milk fat, %	3.58^a	2.80^b	2.14^c	0.14	< 0.010
Milk protein, %	3.10^b	3.06^b	3.42^a	0.10	< 0.010
Lactose, %	4.92^a	3.95^b	2.57^c	0.18	< 0.010
Milk SCC, ×10³ cells/mL	42.8^c	1002^b	7053^a	409	< 0.010
Rumen fermentation parameters
pH	6.68	6.71	6.73	0.03	0.214
NH₃-N, mg/dL	10.5	8.64	8.40	0.40	0.061
RUN, mg/dL	5.90	5.73	6.02	0.20	0.851
LA, mmol/L	0.86^b	0.90^a	0.80^c	0.01	< 0.010
Acetate, mmol/L	64.5^a	60.1^a	41.0^b	1.67	< 0.010
Propionate, mmol/L	27.7^a	25.2^a	19.2^b	0.87	< 0.010
A/P	2.63	2.35	2.45	0.06	0.111
Isobutyrate, mmol/L	0.91	0.85	0.83	0.02	0.325
Butyrate, mmol/L	12.1^a	12.1^a	8.36^b	0.36	< 0.001
Isovalerate, mmol/L	1.58	1.46	1.38	0.05	0.213
Valerate, mmol/L	1.54^a	1.55^a	1.15^b	0.05	< 0.010
TVFAs, mmol/L	109^a	105^a	76.2^b	3.00	< 0.010

Abbreviations: SCC Somatic cell counts, NH₃-N Ammonia nitrogen, RUN Ruminal urea nitrogen, LA Lactic acid, A/P Acetate to propionate ratio, TVFAs Total volatile fatty acids, H Healthy, SM Subclinical mastitis, CM Clinical mastitis, SEM Standard error of mean. ^{a, b, c} values within a row, different letters denote differences between treatment combinations (P < 0.05)

ISSN: 2049-1891