Mocé M L, Santacreu M A, Climent A, Blasco A
Departamento de Ciencia Animal, Universidad Politécnica de Valencia, 46071 Valencia, Spain.
J Anim Sci. 2004 Apr;82(4):1046-52. doi: 10.2527/2004.8241046x.
The aim of this work was to study the effects of the genotype of the dam, the embryo, or their interactions on prenatal growth by performing double-reciprocal embryo transfers between two lines of rabbits divergently selected for uterine capacity. Females from high (n = 53) and low (n = 48) lines were slaughtered at 72 h of gestation, and recovered embryos were transferred to the oviducts of recipient does from the high (n = 23) and low (n = 19) lines. Each recipient doe received eight embryos from the high line into one oviduct and eight embryos from the low line into the other. Recipient does were slaughtered on d 28 of gestation. The percentages of live fetuses at 28 d of gestation were 89.2 and 74% for high and low recipient lines, respectively. Length and weight of the empty uterine horn and weight of the full uterine horn were not affected by either the recipient or by donor line. Fetal weight was affected by the recipient line but not by the donor line. Fetuses gestated in high recipient does were 7% heavier (P < 0.10) than those in the low recipient does. There was a donor and a donor x recipient interaction effect on fetal placental weight. Fetal placental weight was heavier (7%, P < 0.01) for embryos from the low line. Embryos from the high line gestated in low-line uteri showed a lower fetal placenta weight than did low-line embryos gestated in high-line uteri and low-line uteri (P < 0.05). Linear regression coefficients of fetal weight at term on fetal placental weights differed (P < 0.05) for the high and low donors (4.33 +/- 0.28 and 3.41 +/- 0.29 respectively). A significant effect of the donor genotype on individual placental length was observed (P < 0.05), which might have resulted from a smaller individual placental length of low-line embryos gestated high-line uteri (P < 0.10). Neither donor nor recipient lines affected maternal placental weight or available space for fetuses. Fetuses and their fetal placentae were heavier when receiving more than four blood vessels than when receiving less than three blood vessels (13 and 17% respectively, P < 0.05). Neither recipient nor donor genotype affected the number of blood vessels arriving at each live fetus. Thus, fetal weight depends on the maternal genotype, whereas fetal placental weight depends on the embryo genotype in these two lines of rabbits divergently selected for uterine capacity.
本研究旨在通过在两个因子宫容量而被反向选择的兔品系之间进行双 reciprocal 胚胎移植，来研究母本基因型、胚胎基因型或它们的相互作用对产前生长的影响。在妊娠72小时时屠宰来自高（n = 53）、低（n = 48）品系的母兔，回收的胚胎被移植到来自高（n = 23）、低（n = 19）品系的受体母兔的输卵管中。每个受体母兔在一个输卵管中接受8个来自高品系的胚胎，在另一个输卵管中接受8个来自低品系的胚胎。受体母兔在妊娠第28天被屠宰。高、低受体品系在妊娠28天时活胎的百分比分别为89.2%和74%。空子宫角的长度和重量以及满子宫角的重量均不受受体或供体品系的影响。胎儿体重受受体品系影响，但不受供体品系影响。在高受体母兔中孕育的胎儿比在低受体母兔中孕育的胎儿重7%（P < 0.10）。在胎儿胎盘重量上存在供体以及供体×受体的相互作用效应。来自低品系的胚胎的胎儿胎盘较重（7%，P < 0.01）。在低品系子宫中孕育的来自高品系的胚胎，其胎儿胎盘重量低于在高品系子宫和低品系子宫中孕育的低品系胚胎（P < 0.05）。足月时胎儿体重与胎儿胎盘重量的线性回归系数在高、低供体之间存在差异（P < 0.05）（分别为4.33±0.28和3.41±0.29）。观察到供体基因型对个体胎盘长度有显著影响（P < 0.05），这可能是由于在高品系子宫中孕育的低品系胚胎的个体胎盘长度较小（P < 0.10）。供体和受体品系均不影响母体胎盘重量或胎儿的可用空间。当接受超过四条血管时，胎儿及其胎儿胎盘比接受少于三条血管时更重（分别为13%和17%，P < 0.05）。受体和供体基因型均不影响到达每个活胎的血管数量。因此，在这两个因子宫容量而被反向选择的兔品系中，胎儿体重取决于母体基因型，而胎儿胎盘重量取决于胚胎基因型。
