本试验旨在研究妊娠后期宫内生长受限(IUGR)对蒙古绵羊胎儿肝脏脂类代谢能力的影响。选择体重相近、2~3胎次、经同期发情且同期受孕、健康的蒙古绵羊24只,在妊娠90 d时选择6只母羊进行屠宰,其余按体重随机分配到3个组:0.175 MJ/(kg BW^0.75·d)组(RG1组)、0.330 MJ/(kg BW^0.75·d)组(RG2组)和0.670 MJ/(kg BW^0.75·d)组[自由采食组(CG组)],每组6只。饲喂至妊娠140 d,屠宰取胎儿肝脏和血浆用于分析。结果表明:妊娠140 d,RG1组胎儿肝脏重(P<0.01),肝脏干物质(P<0.01)、粗脂肪(P<0.05)、粗蛋白质(P<0.01)、粗灰分(P<0.05)、水分的质量(P<0.01),甘油三酯(P<0.01)、总胆固醇含量(P<0.01),脂蛋白酯酶(P<0.01)、肝酯酶活性(P<0.05)以及血浆中甘油三酯含量(P<0.05)显著或极显著低于CG组,而血浆中β-羟基丁酸(P<0.01)、非酯化脂肪酸(P<0.05)、总胆固醇含量(P<0.05)显著或极显著高于CG组;RG2组肝脏重(P<0.05)、水分质量(P<0.01)、脂蛋白酯酶活性(P<0.01),血浆中甘油三酯含量(P<0.05)显著或极显著低于CG组。妊娠后期IUGR限制了绵羊胎儿肝脏的生长发育,脂肪合成能力受到严重影响,肝脏中脂蛋白酯酶和肝酯酶活性降低,血浆中脂类代谢产物含量升高。

This study aimed to investigate the effects of intrauterine growth restriction (IUGR) during late pregnancy on lipid metabolism in fetal liver of Mongolia ovine. Twenty four healthy Mongolian ewes in second or third parities with similar body weight at synchronization of estrus and superfecundation were selected. Six ewes were slaughtered at the beginning of the experiment (90 d of gestation) and the remaining animals were allocated to three different groups: 0.175 MJ/(kg BW^0.75·d) group (RG1 group), 0.33 MJ/(kg BW^0.75·d) group (RG2 group) and 0.67 MJ/(kg BW^0.75·d) group [ad libitum group (CG group)], each group had six ewes. At 140 d of gestation, ewes were slaughtered and liver and plasma of their fetuses were collected. The results showed as follows: at 140 d of gestation, compared with GC group, the fetal liver weight (P<0.01), the mass of dry matter (P<0.01), ether extract (P<0.05), crude protein (P<0.01), ash (P<0.05) and moisture (P<0.01), the contents of triglycerides (P<0.01) and total cholesterol (P<0.01), and the activities of lipoprotein lipase (P<0.01) and hepatic lipase (P<0.05) in fetal liver as well as triglycerides content (P<0.05) in fetal plasma were significantly or extremely significantly decreased, meanwhile, the contents of β-hydroxybutyrate (P<0.01), nonesterified fatty acid (P<0.05), total cholesterol (P<0.05) in fetal plasma were significantly or extremely significantly enhanced in RG1 group; fetal liver weight (P<0.05), moisture mass (P<0.01) and lipoprotein lipase activity (P<0.01) in fetal liver and triglycerides content (P<0.05) in fetal plasma were significantly or extremely significantly decreased. In conclusion, the growth and development of fetal liver are affected seriously by IUGR during late pregnancy, and the capability of fetal lipid synthesis is decreased, the activities of lipoprotein lipase and hepatic lipase in fetal liver are decreased, and lipid metabolite contents in fetal plasma are greatly enhanced.