Ashworth C J, Dwyer C M, McIlvaney K, Werkman M, Rooke J A
The Roslin Institute and R(D)SVS, University of Edinburgh, Edinburgh, Easter Bush, Midlothian, EH25 9RG, UK.
Reprod Fertil Dev. 2011;23(8):1024-33. doi: 10.1071/RD10290.
This study assessed the effect of feeding 0.75 energy requirements between Days 1 and 90 of pregnancy on placental development and feto-placental amino acid status on Day 125 of pregnancy in Scottish Blackface and Suffolk ewes carrying a single fetus. Such moderate nutrient restriction did not affect placental size, placentome number or the distribution of placentome types. Although fetal weight was unaffected by maternal nutrition, fetuses carried by nutrient restricted mothers had relatively lighter brains and gastrocnemius muscles. Suffolk fetuses were heavier and longer with a greater abdominal circumference, relatively lighter brains, hearts and kidneys, but heavier spleens, livers and gastrocnemius muscles than Blackface fetuses. Total placentome weight was greater in Suffolk than Blackface ewes. Ewe breed had a greater effect on amino acid concentrations than nutrition. Ratios of maternal to fetal amino acid concentrations were greater in Suffolk ewes than Blackface ewes, particularly for some essential amino acids. The heavier liver and muscles in Suffolk fetuses may suggest increased amino acid transport across the Suffolk placenta in the absence of breed differences in gross placental efficiency. These data provide evidence of differences in nutrient handling and partitioning between the maternal body and the fetus in the two breeds studied.
本研究评估了在怀孕第1天至第90天期间给予0.75能量需求对怀有单胎的苏格兰黑脸和萨福克母羊怀孕第125天胎盘发育和胎儿-胎盘氨基酸状态的影响。这种适度的营养限制并未影响胎盘大小、胎盘叶数量或胎盘叶类型的分布。尽管胎儿体重不受母体营养的影响，但营养受限母羊所怀胎儿的大脑和腓肠肌相对较轻。与黑脸胎儿相比，萨福克胎儿更重、更长，腹围更大，大脑、心脏和肾脏相对较轻，但脾脏、肝脏和腓肠肌更重。萨福克母羊的胎盘叶总重量比黑脸母羊更大。母羊品种对氨基酸浓度的影响大于营养。萨福克母羊的母体与胎儿氨基酸浓度之比高于黑脸母羊，尤其是对于一些必需氨基酸。萨福克胎儿较重的肝脏和肌肉可能表明，在胎盘总体效率无品种差异的情况下，萨福克胎盘的氨基酸转运增加。这些数据提供了所研究的两个品种在母体与胎儿之间营养处理和分配差异的证据。
