Table 5.
Timing and amount of feed delivered to sows prior to farrowing on subsequent reproductive performance1
| Response | 2.7 kg × 1 delivery | 0.68 kg × 4 deliveries | Ad libitum × 4 deliveries | SEM | P−value |
|---|---|---|---|---|---|
| Count, n | 188 | 188 | 186 | −− | −− |
| Wean to estrus interval2, day | 4.6 | 4.0 | 4.3 | <0.1823 | 0.162 |
| Estrous by day 7, % | 95.7 | 96.3 | 96.2 | 1.47 | 0.958 |
| Estrous by day 20, % | 97.3 | 99.4 | 98.9 | 1.17 | 0.204 |
| Conception rate4, % | 89.4 | 88.3 | 86.6 | 2.51 | 0.703 |
| Farrowing rate5, % | 85.1 | 87.8 | 85.0 | 2.62 | 0.673 |
| Subsequent litter | |||||
| Count6, n | 160 | 165 | 158 | −− | −− |
| Total born, n | 13.7 | 14.0 | 13.7 | 0.26 | 0.492 |
| Born alive, % | 93.4 | 93.3 | 92.8 | 0.55 | 0.809 |
| Stillborn, % | 6.6 | 6.7 | 7.2 | 0.59 | 0.809 |
1A total of 562 mixed parity sows remaining in the herd were used to collect subsequent reproductive performance. Sows were culled after lactation due to old age (n = 160), injury (n = 3), or infertile (n = 2).
2Sows were monitored for 42 d after weaning for signs of estrus.
3Heterogenous variance by treatment, SEM = 0.18, 0.17, and 0.17 for sows receiving 2.7 kg × 1 delivery, 0.68 kg × 4 deliveries, and ad libitum × 4 deliveries, respectively.
4Sows confirmed pregnant at day 30 divided by total number bred.
5Sows farrowed divided by total number bred.
6Sows that farrowed a subsequent litter.