Table 2.
Relationship between average corpora lutea diameter measured by transrectal ultrasonography (DIAMTUS) and litter characteristics at birth
| DIAMTUS1, mm | Litter size | Parity | ||
|---|---|---|---|---|
| Dependent variables | β (SEM) | P-value | P-value | P-value |
| Gestational length, d | 0.48 (0.26) | 0.06 | ns2 | ns |
| Litter size3 | –0.098 (0.43) | 0.82 | – | ns |
| Number of live born | –0.084 (0.43) | 0.84 | – | ns |
| Number of stillborn4 | –0.015 (0.22) | 0.95 | 0.02 | 0.01 |
| Number of mummies | –0.013 (0.10) | 0.90 | ns | ns |
| Average piglet BW5, g | 37.57 (17.84) | 0.04 | < 0.0001 | ns |
| SD BW5, g | 24.25 (10.37) | 0.02 | ns | ns |
| Average live born piglets BW5, g | 32.98 (18.41) | 0.08 | < 0.0001 | ns |
| SD BW live born5, g | 27.33 (10.52) | 0.01 | ns | ns |
| Litter BW, kg | 0.81 (0.47) | 0.09 | < 0.0001 | ns |
1Average calculated based on the diameter of the 5 biggest corpora lutea in each ovary (10 per sow) measured by TUS.
2ns = P > 0.05.
3Litter size is the sum of piglets born alive (live born) and stillborn piglets.
4Interaction between parity (PC) and litter size (LS) classes (P = 0.002): PC1 × LS1 (n = 9): 0.67 ± 0.55b; PC2 × LS1 (n = 12): 0.48 ± 0.48b; PC3 × LS1 (n = 6): 1.54 ± 0.47ab; PC2 × LS2 (n = 12): 1.02 ± 0.49b; PC2 × LS2 (n = 12): 2.01 ± 0.49b; PC3 × LS2 (n = 11): 0.92 ± 0.49ab; PC1 × LS3 (n = 13): 0.81 ± 0.66b; PC2 × LS3 (n = 12): 1.58 ± 0.51ab; PC3 × LS3 (n = 13): 3.83 ± 0.47a.
5Piglets were weighed within 24 h after birth (BW).