Table 3 Pearson's rank correlation coefficients for the relationships between concentrations of estrogen, progesterone and cortisol in serum and peak systolic velocity (PSV), blood flow volume (BFV), time-averaged maximum velocity (TAMV), pulsatility index (PI), resistance index (RI) systolic/diastolic velocity (S/D), and peak velocity (PV) of blood flow through vaginal artery (V) using Doppler ultrasonography parameters (D) in Holstein cows during the GnRH PGF2α management program. Bold parameters are R value and reverse bolding indicates P value

P4

1

-0.18

0.94**

0.75**

0.98**

0.33

-0.48

-0.44

0.69**

0.49

P4

0.5

0.000

0.001

0.01

0.22

0.06

0.09

0.01

0.06

E2

-0.18

1

-0.26

-0.31

-0.09

-0.17

-0.1

0.18

-0.04

-0.27

E2

0.5

0.34

0.25

0.7

0.047

0.7

0.5

0.86

0.32

Cortisol

0.94**

-0.26

1

0.76**

-0.05

0.26

-0.54*

-0.37

0.12

0.37

cortisol

0.000

0.34

0.001

0.83

0.34

0.03

0.16

0.64

0.17

V-PSV

0.75**

-0.31

0.76**

1

-0.13

0.1

0.34

-0.31

0.4

0.41

V-PSV

0.001

0.25

0.001

0.62

0.7

0.2

0.24

0.1

0.12

V-TAMV

0.98

-0.17

-0.05

-0.13

1

0.74**

-0.81*

-0.34

- 0.74*

0.5

V-TAMV

0.01

0.7

0.83

0.62

0.001

0.01

0.21

0.01

0.05

V-BFV

0.33

-0.17

0.26

0.1

0.74**

1

0.02

-0.3

0.25

0.82**

V-BFV

0.22

0.047

0.34

0.7

0.001

0.9

0.26

0.35

0.000

V-PI

-0.48

-0.1

-0.54*

0.34

-0.81*

0.02

1

-0.21

0.4

-0.04

V-PI

0.06

0.72

0.03

0.2

0.01

0.9

0.43

0.13

0.88

V-RI

-0.44

0.18

-0.37

-0.31

-0.34

-0.3

-0.21

1

0.18

-0.46

V-RI

0.09

0.5

0.16

0.24

0.74*

0.26

0.43

0.5

0.08

V-S/D

0.69**

-0.04

0.12

0.4

0.01

0.25

0.4

0.18

1

0.26

V-S/D

0.01

0.8

0.64

0.1

0.52

0.35

0.13

0.5

0.33

V-D

0.49

-0.27

0.37

0.41

0.5

0.82**

-0.04

-0.46

0.26

1

V-D

0.06

0.32

0.17

0.12

0.05

0.000

0.88

0.08

0.33