Effects of early gestational undernutrition on fetal growth, organ development, and placentomal composition in the bovine
Effects of early gestational undernutrition on fetal growth, organ development, and placentomal composition in the bovine
复制标题
DOI：
10.2527/jas.2008-1672
复制
发表时间：
2009-06-01
影响因子：
3.3
通讯作者：
Ford, S. P.
中科院分区：
文献类型：
--
作者：
Long, N. M.;Vonnahme, K. A.;Ford, S. P.
胎儿宫内生长受限（IUGR）是众所周知的负面影响后代的健康出生后。本研究评估了妊娠早期营养不良后再补充营养对牛胎儿和胎盘生长的影响。从妊娠第30天到第125天，对30头与一个父系交配并孕育雌性胎儿的经产肉牛进行饲喂，以满足NRC建议（对照; n = 15）或低于NRC建议（68.1%的NEm和86.7%的MP建议;营养限制，NR; n = 15）。在妊娠第125天，对10头对照和10头NR奶牛进行尸检。在妊娠第190天，使剩余5头NR奶牛达到与剩余5头对照奶牛相似的BW和BCS;在妊娠第245天对两组进行尸检。对照奶牛妊娠第125天的胎仔重量为948 +/- 14 g（n = 10）;然而，NR奶牛的胎仔重量分为2个不同的组：NR非IUGR奶牛的胎仔重量与对照奶牛相似（974 +/- 20 g，n = 6），而NR IUGR母牛的胎儿体重降低（773 +/- 23 g，n = 4; P < 0.01）。NR IUGR组胎儿脑重占胎儿体重的百分比较其他两组胎儿增加（接近11%; P < 0.01）。与对照组胎儿相比，NR IUGR胎儿的胎儿心脏重量占胎儿重量的百分比也倾向于增加（接近10%; P = 0.08）。与NR非IUGR奶牛和对照奶牛相比，营养限制IUGR奶牛表现出子叶重量降低（P < 0.01），两者相似（分别为192 +/- 27 vs. 309 +/- 22和337 +/- 17 g）。与NR非IUGR奶牛和对照奶牛相比，NR IUGR奶牛的胎盘总表面积也有减少的趋势（P = 0.07），两者也相似（分别为685.0 +/- 45.6 vs. 828.7 +/- 37.2和790.7 +/- 28.9 mm 2）。在妊娠第245天，NR和对照奶牛的胎仔重量和肉阜重量相似;然而，NR与对照奶牛的子叶重量降低（1，430 +/- 133 vs. 2，137 +/- 133 g，P < 0.01）。NR IUGR奶牛在妊娠第125天的胎儿生长下降与子叶重量下降和胎盘表面积减少有关。NR奶牛通过从第126天开始的重新调整恢复到与对照奶牛相似的BW和BCS，导致NR和对照奶牛在妊娠第245天的胎重相似。因此，如果妊娠早期营养不良的奶牛在妊娠后半期接受饲料补充以确保正常的出生体重，胎儿IUGR可能无法被发现。
Fetal intrauterine growth restriction (IUGR) is known to negatively affect offspring health postnatally. This study evaluated the impacts of early gestational undernutrition followed by realimentation on bovine fetal and placental growth. Thirty multiparous beef cows bred to a single sire and gestating female fetuses were fed to meet NRC recommendations (control; n = 15) or fed below NRC recommendations (68.1% of NEm and 86.7% of MP recommendations; nutrient restricted, NR; n = 15) from d 30 to 125 of gestation. On d 125 of gestation, 10 control and 10 NR cows were necropsied. The remaining 5 NR cows were realimented to achieve similar BW and BCS with the remaining 5 control cows by d 190 of gestation; both groups were necropsied at d 245 of gestation. Fetal weight at d 125 of gestation was 948 +/- 14 g (n = 10) for control cows; however, fetal weights of NR cows fell into 2 distinct groups: NR non-IUGR cows had fetal weights similar to control cows (974 +/- 20 g, n = 6), whereas fetal weights of NR IUGR cows were reduced (773 +/- 23 g, n = 4; P < 0.01). Fetal brain weight as a percentage of fetal weight was increased (similar to 11%; P < 0.01) in the NR IUGR fetuses compared with fetuses from the other 2 groups, which were similar. Fetal heart weight as a percentage of fetal weight also tended to be increased (similar to 10%; P = 0.08) in NR IUGR fetuses compared with control fetuses. Nutrient-restricted IUGR cows exhibited reduced (P < 0.01) cotyledonary weights compared with NR non-IUGR and control cows, which were similar (192 +/- 27 vs. 309 +/- 22, and 337 +/- 17 g, respectively). Total placentome surface area also tended to be reduced (P = 0.07) in NR IUGR cows compared with NR non-IUGR and control cows, which again were similar (685.0 +/- 45.6 vs. 828.7 +/- 37.2 and 790.7 +/- 28.9 mm(2), respectively). On d 245 of gestation, fetal weights and caruncle weight were similar for NR and control cows; cotyledonary weights, however, were reduced in NR vs. control cows (1,430 +/- 133 vs. 2,137 +/- 133 g, P < 0.01). Decreased fetal growth in NR IUGR cows on d 125 of gestation was associated with decreased cotyledonary weights and reduced placentomal surface areas. The return of NR cows to a BW and BCS similar to that of control cows through realimentation beginning on d 126 resulted in similar fetal weights of NR and control cows by d 245 of gestation. Thus, a bout of fetal IUGR may go undetected if cows undernourished during early gestation receive feed supplementation in the second half of gestation to assure normal birth weight.