Table 1. Effects of the different degrees of synchrony between recipients and donors on the farrowing rates and litter sizes after nonsurgical deep intrauterine transfers of 30 fresh embryos at the morula and/or unhatched blastocyst stages.
| Synchrony recipients–donors (h)* |
||||
| −24 | 0 | + 24 | + 48 | |
| Recipients, N | 9 | 31 | 74 | 18 |
| Pregnancy rate, N (%) | 1 (11.1)a | 19 (61.3)b | 63 (85.1)c | 9 (50.0)ab |
| Farrowing rate, N (%) | – | 19 (61.3)a | 60 (81.1)b | 9 (50.0)a |
| Total born (mean ± SEM) | – | 10.5 ± 0.8 | 9.6 ± 0.4 | 9.2 ± 1.0 |
| Born alive (mean ± SEM) | – | 10.1 ± 0.8 | 8.9 ± 0.4 | 8.6 ± 0.9 |
| Stillborn (mean ± SEM) | – | 0.4 ± 0.2 | 0.7 ± 0.1 | 0.6 ± 0.3 |
| Piglet birth weight (kg; mean ± SEM) | – | 1.2 ± 0.1 | 1.7 ± 0.1 | 1.6 ± 0.1 |
| Sex ratio at birth (%; male/female) | – | 47.7/52.3 | 49.0/51.0 | 46.4/53.6 |
| Piglet production efficiency (%) | – | 20.6d | 24.0d | 14.3e |
*Recipients in estrus before (–) or after (+) donors. a,b,c,d,e Different superscripts within the same row indicate differences: a,b,c P<0.05; d,e P<0.001.