Table 6.

Temperature measurements (°C) of the body surface of sows analyzed for different days of observed standing heat

Items	Observations2) Subgroups3)	4DPW1) (n = 40)5) (14:26)	5DPW (n = 39)6) (16:23)	6DPW (n = 20)7) (12:8)	7DPW (n = 13)8) (6:7)	NDPW1) (n = 204))9) (5:15)	SEM	p-value
Body surface
Vulva		34.50±0.047W,b	34.68±0.047W,ab	34.75±0.069W,a	34.62±0.076W,ab	34.54±0.078WX,ab	0.032	0.041
Udder		34.31±0.048X,c	34.34±0.048X,bc	34.56±0.071W,b	34.53±0.078W,b	34.83±0.079W,a	0.033	<0.001
Ear		33.81±0.058Y,b	34.23±0.058XY,a	34.28±0.085X,a	34.21±0.094X,a	34.31±0.095X,a	0.039	<0.001
Back		33.81±0.045Y,c	34.10±0.046Y,b	34.26±0.067X,ab	34.32±0.074WX,a	34.27±0.075X,ab	0.032	<0.001
SEM		0.024	0.024	0.036	0.041	0.041	-	-
p-value		<0.001	<0.001	<0.001	0.001	<0.001	-	-
Temperature difference between target sites
VU		0.19±0.046ab	0.34±0.047a	0.19±0.069ab	0.09±0.075b	−0.28±0.077c	0.031	<0.001
VE		0.70±0.048a	0.45±0.049b	0.47±0.071b	0.41±0.078bc	0.24±0.080c	0.031	<0.001
VB		0.68±0.063a	0.48±0.063ab	0.44±0.093ab	0.27±0.102b	0.22±0.104b	0.045	0.003

Value shown is the mean±standard deviation from day 1 to day 8 post-weaning.

SEM, standard error of the mean; VU, vulva - udder; VE, vulva - ear base; VB, vulva - central back.

¹⁾DPW, day post-weaning on which heat was first shown; NDPW, day post-weaning on which not detected in standing heat.

²⁾Number of sows observed standing heat.

³⁾Number of sows in AM and PM subgroups (AM:PM).

⁴⁾Number of sows observed non-standing heat.

⁵⁾Sample size = 40 sows×4 measurements per day×8 days.

⁶⁾Sample size = 39 sows×4 measurements per day×8 days.

⁷⁾Sample size = 20 sows×4 measurements per day×8 days.

⁸⁾Sample size = 13 sows×4 measurements per day×8 days.

⁹⁾Sample size = 20 sows×4 measurements per day×8 days.

^a–cMeans within a row without a common superscript letter differ (p<0.05).

^W–YMeans within a column without a common superscript letter differ (p<0.05).