Department of Animal Science, Oklahoma Agricultural Experiment Station, Stillwater, OK 74078-0425, USA.
J Anim Sci. 2010 Oct;88(10):3251-61. doi: 10.2527/jas.2009-2512. Epub 2010 Jun 4.
Angus x Hereford heifers (15 mo and artificially inseminated to a single sire) were used to evaluate the effect of prenatal nutritional restriction on postnatal growth and development. At d 32 of gestation, dams were stratified by BW and BCS and allotted to a low-nutrition [55% of NRC (1996) requirements, n = 10] or moderate-nutrition [100% of NRC (1996) requirements, n = 10] diet. After 83 d of feeding, dams were commingled and received a diet in excess of requirements. Dams were allowed to calve naturally, and birth weights and growth of calves were recorded. Bulls were castrated at birth. Steers (16 mo of age, 5 per treatment) received a high-concentrate diet ad libitum to a constant age (88 ± 1 wk). Steers were slaughtered and weights of the empty body and organs were recorded. Samples of organs, muscle (complexus), and perirenal and subcutaneous adipose tissue were stored at -80 degrees C, and then DNA and protein concentrations were quantified and expression of genes associated with fatty acid metabolism and glucose uptake were measured in adipose and muscle tissue. Dams had similar (P > 0.33) BW and BCS at the beginning of the experiment. At the end of restriction, dams on the low-nutrition diet weighed less (P ≤ 0.01) and had less BCS (P < 0.001) than those on the moderate-nutrition diet. Length of gestation was 274 ± 2 d for dams in the low-nutrition treatment and 278 ± 2 d (P = 0.05) for dams in the moderate-nutrition treatment. Nutrient restriction during gestation did not influence birth weight or postnatal growth of calves. Lungs and trachea of steers whose dams were fed the low-nutrition diet weighed less (P = 0.05) at slaughter than those of steers whose dams were fed the moderate-nutrition diet; weights of other organs were not influenced by treatment. Complexus muscle from steers whose dams were fed the low-nutrition diet had a greater (P = 0.04) concentration of DNA and larger muscle fiber area compared with steers whose dams were fed the moderate-nutrition diet. Abundance of mRNA for fatty acid binding protein 4, fatty acid translocase, and glucose transporter 4 was less in perirenal adipose tissue of steers whose dams were fed the low-nutrition diet compared with those whose dams were fed the moderate-nutrition diet. Nutritional restriction of dams during early gestation did not alter postnatal calf growth. However, concentrations of DNA in muscle tissue and muscle fiber area were greater in steers from dams exposed to restricted nutrient intake during early gestation.
安格斯和海弗福德小母牛（15 月龄，人工授精至单一公牛）用于评估产前营养限制对产后生长和发育的影响。在妊娠第 32 天，根据体重和体况将母羊分层，并分配到低营养[NRC（1996 年）需求的 55%，n=10]或中等营养[NRC（1996 年）需求的 100%，n=10]饮食。喂养 83 天后，母羊混合喂养，并摄入超过需求的饮食。母羊自然分娩，记录出生体重和小牛的生长情况。公牛出生时被去势。公牛（16 月龄，每处理 5 头）自由摄入高浓缩饲料，直至达到恒定年龄（88±1 周）。公牛被屠宰，记录空体和器官的重量。器官、肌肉（胸锁乳突肌）、肾周和皮下脂肪组织的样本在-80°C 下储存，然后定量测定 DNA 和蛋白质浓度，并测量与脂肪代谢和葡萄糖摄取相关的基因在脂肪和肌肉组织中的表达。实验开始时，母羊的体重和体况相似（P>0.33）。在限制结束时，低营养饮食组的母羊体重较轻（P≤0.01），体况评分较低（P<0.001），低于中等营养饮食组。低营养处理组的母羊妊娠期为 274±2d，中等营养处理组的母羊妊娠期为 278±2d（P=0.05）。妊娠期的营养限制并没有影响小牛的出生体重或产后生长。与母羊喂养中等营养饮食的公牛相比，母羊喂养低营养饮食的公牛的肺部和气管在屠宰时较轻（P=0.05）；其他器官的重量不受处理的影响。与母羊喂养中等营养饮食的公牛相比，母羊喂养低营养饮食的公牛的胸锁乳突肌的 DNA 浓度更高（P=0.04），肌纤维面积更大。与母羊喂养中等营养饮食的公牛相比，低营养饮食组公牛的肾周脂肪组织中脂肪酸结合蛋白 4、脂肪酸转运蛋白和葡萄糖转运蛋白 4 的 mRNA 丰度较低。妊娠期早期母羊的营养限制并没有改变产后小牛的生长。然而，在经历早期营养限制的母羊的后代公牛的肌肉组织中的 DNA 浓度和肌纤维面积更大。
