Table 4 The ruminal fluid composition, blood metabolites and hormone level in the dairy cows fed the low-concentrate (LC) diet and high-concentrate (HC) diet

Total VFA(mmol/L)

92.91

107.64^a

3.66

<0.05

Molar proportion, mmol/mol

Acetate

454.51

440.55

3.10

0.47

Propionate

247.68

281.83^b

2.41

<0.01

Isobutyrate

25.19

24.68

0.38

0.83

Butyrate

210.11

195.99

1.77

0.17

Isovalerate

36.31

34.52

0.67

0.67

Valerate

21.25

19.93

0.24

0.38

Caproate

4.95

2.49^b

0.17

<0.01

Acetate:Propionate

1.84

1.57^a

0.02

<0.05

Propionate:Butyrate

1.18

1.44^b

0.05

<0.01

Lactic acid

0.96

1.55^b

0.20

<0.01

Plasma biochemical parameter ⁴

TG (mmol/L)

0.28

0.21^a

0.05

<0.05

NEFA (mmol/L)

1.16

0.48^ab

0.07

<0.001

TCH (mmol/L)

2.21

1.69^b

0.31

<0.01

GLU (mg/dL)

45.23

56.02^b

4.54

<0.01

Hormone level ⁴

Insulin (μIU/mL)

16.95

21.57^a

1.01

<0.05

Glucagon (pg/mL)

191.23

161.02

18.28

0.28

Insulin:Glucacon

0.10

0.16^c

0.01

0.07