Croskerry P G, Smith G K, Hall S, Shepard B J
Biol Neonate. 1978;33(1-2):31-8. doi: 10.1159/000241048.
The effects on fetal and placental growth of differential litter size reduction on day 10 (LR10) and day 13 (LR13) were determined in the rat. LR10 resulted in significant increments in placental weight, fetal body and brain weight, and brain protein content in the survivors at day 21. A marginal effect on brain cellularity (DNA) was observed. Values for these parameters generally followed the extent of reduction. Placenta weight was also related to original litter size. In contrast, LR13 which was associated with survival of supernumerary placentae (those without a fetus) produced no growth enhancement. Prenatal development was discussed in terms of general systemic influences and hormonal regulatory mechanisms.
在大鼠中确定了第10天（LR10）和第13天（LR13）不同程度减少窝仔数对胎儿和胎盘生长的影响。LR10导致第21天时存活仔鼠的胎盘重量、胎儿体重和脑重以及脑蛋白含量显著增加。观察到对脑细胞数量（DNA）有轻微影响。这些参数的值通常随减少程度而变化。胎盘重量也与原始窝仔数有关。相比之下，与多余胎盘（无胎儿的胎盘）存活相关的LR13未产生生长促进作用。从一般全身影响和激素调节机制方面讨论了产前发育情况。
