Skip to main content

Table 2 Cardiac activity parameters with shift towards parasympathetic nervous system activity in horses at successive periods of the test of predator vocalization (means ± standard deviations)

From: The intensity of physiological and behavioral responses of horses to predator vocalizations

Horse pedigree

group

Prestimulus period

Stimulus period

Poststimulus period

RR during testing the wolf sound

  ¾TB

1559 ± 223 ax

1232 ± 312 ay

1513 ± 17 ax

  ½TB

1292 ± 169 bx*

1136 ± 337 ax*

1444 ± 234 ay*

  ¼TB

1392 ± 129 bx*

1189 ± 270 ay

1469 ± 137 ax*

RR during testing the leopard sound

  ¾TB

1431 ± 413 ax

1307 ± 431 ax

1575 ± 327 ax

  ½TB

1033 ± 150 bx

861.2 ± 206 by

1079 ± 140 bx

  ¼TB

1052 ± 179 bxy

909.3 ± 160 bx

1106 ± 148 by

RMSSD during testing the wolf sound

  ¾TB

104.0 ± 25.3 ax

86.9 ± 17.5 ay*

101.8 ± 5.6 ax*

  ½TB

79.0 ± 27.9 ax*

91.1 ± 48.6 axy*

102.9 ± 37.0 ay*

  ¼TB

85.0 ± 19.5 ax*

70.5 ± 40.2 ax

81.1 ± 31.8 ax

RMSSD during testing the leopard sound

  ¾TB

88.0 ± 26.4 ax

188.2 ± 136.3 ay

66.9 ± 18.5 abz

  ½TB

55.6 ± 23.8 bx

57.0 ± 51.2 bx

59.9 ± 21.6 ax

  ¼TB

59.6 ± 22.5 bx

54.8 ± 31.3 bx

71.0 ± 21.2 by

HF during testing the wolf sound

  ¾TB

2700 ± 1238 ax

2048 ± 965 ax*

2582 ± 267 ax*

  ½TB

1596 ± 901 bx*

2395 ± 1271 ay*

2801 ± 1064 ay*

  ¼TB

1670 ± 603 bx*

1480 ± 866 bx

1709 ± 1621 bx

HF during testing the leopard sound

  ¾TB

2412 ± 1832 ax

1227 ± 370 ay

993 ± 437 ay

  ½TB

792 ± 558 bx

1257 ± 242 ay

1008 ± 700 ax

  ¼TB

990 ± 697 bx

991 ± 330 ax

1763 ± 789 by

  1. ¾TB, ½TB, ¼TB – horse groups with 75%, 50% and 25% Thoroughbred ancestry within the parental and grandparental generations, respectively
  2. RR beat-to-beat intervals, RMSSD root mean square of the successive differences in RR, HF high frequency component of the power spectrum
  3. Means marked with different letters significantly differ (according to Tukey’s HSD test) at p < 0.05: a, b - in columns (between different horse pedigree groups exposed to the same predator sound); x, y, z - in rows (between the same horse pedigree group at different test periods); *between the same horse pedigree group exposed to different predator sounds in analogical period of the test