Table 4. Reproductive parameters of the recipients in estrus 48 h later than the donors after nonsurgical deep-uterine transfer of 30 fresh porcine embryos.
| Embryonic stage* |
||
| Morula | Blastocyst | |
| Recipients, N | 10 | 8 |
| Pregnancy rate, N (%) | 3 (30.0)a | 7 (87.5)b |
| Farrowing rate, N (%) | 3 (30.0)a | 7 (87.5)b |
| Total born (mean ± SEM) | 7.3 ± 2.3e | 10.4 ± 0.7f |
| Born alive (mean ± SEM) | 7.0 ± 2.0e | 9.6 ± 0.7f |
| Stillborn (mean ± SEM) | 0.3 ± 0.3 | 0.8 ± 0.5 |
| Piglet birth weight (kg; mean ± SEM) | 1.7 ± 0.2 | 1.5 ± 0.2 |
| Sex ratio at birth (%; male/female) | 52.4/47.6 | 43.7/56.3 |
| Piglet production efficiency (%) | 7.0c | 27.9d |
*Embryos at the morula and unhatched blastocyst stages were collected from donors at days 5 and 6 (day 0=onset of estrus), respectively, and were transferred into the recipients on days 3 and 4 of the cycle, respectively. a,b,c,d Different superscripts within the same row indicate differences: a,b P<0.05; c,d P<0.001. e,f Different superscripts within the same row indicate tendencies for differences (P=0.09).