Table 1. Descriptive statistics of the Yorkshire × Landrace F2 crossbred P1, P3, and P6

Parity Avg SD Med Min Max p-value
Sows traits
 Gestation length (days) P1 115.4 ± 1.3 116 114 117 <0.05
P3 115.5 ± 1.2 115 114 117
P6 116.7 ± 0.9 117 115 118
 Total number of piglets born (heads) P1 16.8 ± 1.8 17 14 19 0.113
P3 15.5 ± 3.1 15 12 21
P6 12.4 ± 3.2 12 7 17
 Number of piglets born live (heads) P1 15.6 ± 2.1 16 13 18 0.118
P3 14.0 ± 3.2 13 10 19
P6 11.0 ± 3.4 11 6 16
 Number of piglets still born (heads) P1 0.2 ± 0.5 0 0 1 0.151
P3 1.3 ± 1.5 1 0 4
P6 1.1 ± 0.3 0 0 1
 Total piglet birth weight (kg) P1 16.8 ± 2.1 16 14 20 0.117
P3 14.7 ± 3.2 14 10 19
P6 12.4 ± 3.5 12 7 18
Weaning traits
 Weaning period (days) P1 23.0 ± 7.8 24 13 34 0.170
P3 20.7 ± 2.7 19 18 24
P6 20.2 ± 4.8 19 16 32
 Weaning piglets (heads) P1 10.4 ± 1.5 11 8 12 <0.05
P3 10.0 ± 0.6 10 9 11
P6 10.4 ± 1.7 11 8 12
 Total piglets weaning weight (kg) P1 54.9 ± 10.2 56 38 66 0.377
P3 58.4 ± 13.6 59 43 77
P6 62.0 ± 10.4 58 54 81
Durations traits
 Duration of farrowing (min) P1 25.9 ± 6.1 26 18 33 0.355
P3 29.5 ± 3.8 29 25 33
P6 22.2 ± 13.3 21 5 42
 Duration of placenta expulsion (min) P1 141.0 ± 263.0 15 0 536 0.447
P3 192.0 ± 423.0 17 0 1,056
P6 663.0 ± 1,802.0 23 0 5464
 Time from last piglet to first placenta (min) P1 74.0 ± 117.0 25 0 248 0.206
P3 34.0 ± 37.0 31 0 80
P6 87.0 ± 79.0 83 1 248
 Average birth interval (min) P1 125.6 ± 94.8 114 0 357 0.156
P3 229.3 ± 125.0 229 0 455
P6 167.1 ± 92.0 189 0 340
 Behavior of tail wagging (count) P1 5.3 ± 4.3 4 1 16 0.065
P3 5.6 ± 2.3 4 2 9
P6 7.8 ± 6.7 5 0 24
Twenty sows used in this study were between the first and sixth parity in gilts (P1), parity 2–5 (P3), and parity 6–9 (P6).
Avg, average; SD, standard deviation; Med, median; Min, minimum; Max, maximum.