Table 4.
Least-squares means for the effect of Birth Weight Category on piglet weights, average daily gain, preweaning mortality, and the causes and timing of mortality
| Item | Birth Weight Category1 | ||||
|---|---|---|---|---|---|
| Light | Medium | Heavy | SEM | P-value | |
| Number of piglets | 61 | 238 | 262 | – | – |
| Piglet weight, kg | |||||
| Birth | 0.90c | 1.27b | 1.76a | 0.016 | <0.0001 |
| Weaning | 3.99c | 5.38b | 6.76a | 0.145 | <0.0001 |
| Average daily gain, kg | 0.159c | 0.211b | 0.258a | 0.0073 | <0.0001 |
| Preweaning mortality, % | 37.7a | 11.8b | 7.5b | – | <0.0001 |
| Number of mortalities | 24 | 31 | 22 | – | – |
| Cause of mortality, % of total mortality within treatment | |||||
| Crushing | 37.5 | 54.8 | 54.5 | – | 0.40 |
| Starvation | 62.5 | 38.7 | 36.4 | – | 0.15 |
| Other | 0.0 | 6.5 | 9.1 | – | 0.94 |
| Time of mortality, % of total mortality within treatment | |||||
| Day 1 to 2 | 0.0 | 9.7 | 13.6 | – | 0.91 |
| Day 1 to 7 | 66.7 | 51.6 | 40.9 | – | 0.23 |
| Day 8 to weaning | 33.3 | 48.4 | 59.1 | – | 0.23 |
| Age at death, d2 | 7.0 | 8.0 | 9.3 | 1.17 | 0.30 |
1Light = birth weights between 0.5 and 1.0 kg; Medium = birth weights between 1.0 kg and 1.5 kg; Heavy = birth weights > 1.5 kg.
2Data transformed using a square transformation to correct for normality and homogeneity of variance of the residuals.
a,b,cMeans with differing superscripts differ at P ≤ 0.05.