Xu S-Y, Wu De, Guo H-Y, Zheng A-R, Zhang G
Key Laboratory for Animal Disease Resistance Nutrition of the Ministry of Education of China, Institute of Animal Nutrition, Sichuan Agricultural University, Ya'an, China.
Reprod Domest Anim. 2010 Aug;45(4):685-93. doi: 10.1111/j.1439-0531.2008.01331.x. Epub 2009 Jan 21.
Appropriate feed intake level would enhance embryo survival. This study investigated the relationship among feed intake level, embryo survival, hormone secretion and mRNA expression. Fifty-four Landrace x Yorkshire crossbred gilts were allotted to three treatment groups of high (H, 2 x maintenance), medium (M, 1.2 x maintenance) and low (L, 0.6 x maintenance) after mating, to study the effect of feed intake levels on embryo survival, hormone secretion and mRNA expression of leptin, obesity receptor (ob-R), signal transducer and activator of transcription-3 (STAT3), DNA methyltransferase 1 (DNMT1), retinol-binding protein 4 (RBP4), fibroblast growth factor receptor 2 (FGFR2) and progesterone receptor (PGR) in embryos. Blood samples and embryos were collected for hormone concentrations determination and gene expression analysis. Slaughter weight, total weight gain and net weight gain were affected (p < 0.05) by dietary treatment. Embryonic survival was 80.23% and 78.45% in M group on days 25 and 35 of pregnancy, respectively, and was greater (p < 0.05) in M than H and L groups. Serum insulin-like growth factor-I and leptin concentrations enhanced (p < 0.05) with the increased feed intake, but progesterone concentrations were lower (p < 0.05) in H than M and L groups and no difference (p > 0.05) between M and L on days 25 and 35 of pregnancy. Real-Time PCR indicated that gene expression pattern of leptin, ob-R, STAT3 and DNMT1 were the highest (p < 0.05) in H group on days 25 and 35 of pregnancy. Transcript expression level of RBP4 and FGFR2 were the highest (p < 0.05) in M group on days 25 and 35 of pregnancy. Significantly higher (p < 0.05) expression of PGR was observed in L group on day 25 and in M group on day 35 of pregnancy. Our data suggest that 1.2 x maintenance feed intake level promoted the appropriate hormone secretion and enhanced genes expression in RBP4, FGFR2 and PGR, and thus resulted in better embryo survival compared with the high and low groups.
适宜的采食量水平可提高胚胎存活率。本研究调查了采食量水平、胚胎存活率、激素分泌和mRNA表达之间的关系。54头长白×约克夏杂交后备母猪在配种后被分为高（H，2倍维持量）、中（M，1.2倍维持量）、低（L，0.6倍维持量）三个处理组，以研究采食量水平对胚胎存活率、激素分泌以及胚胎中瘦素、肥胖受体（ob-R）、信号转导子和转录激活子3（STAT3）、DNA甲基转移酶1（DNMT1）、视黄醇结合蛋白4（RBP4）、成纤维细胞生长因子受体2（FGFR2）和孕激素受体（PGR）mRNA表达的影响。采集血样和胚胎用于激素浓度测定和基因表达分析。屠宰体重、总增重和净增重受日粮处理影响（p<0.05）。妊娠第25天和第35天，M组的胚胎存活率分别为80.23%和78.45%，且M组高于H组和L组（p<0.05）。血清胰岛素样生长因子-I和瘦素浓度随采食量增加而升高（p<0.05），但妊娠第25天和第35天，H组的孕激素浓度低于M组和L组，M组和L组之间无差异（p>0.05）。实时荧光定量PCR表明，妊娠第25天和第35天，H组的瘦素、ob-R、STAT3和DNMT1基因表达模式最高（p<0.05）。妊娠第25天和第35天，M组的RBP4和FGFR2转录表达水平最高（p<0.05）。妊娠第25天L组和第35天M组的PGR表达显著更高（p<0.05）。我们的数据表明，1.2倍维持量的采食量水平促进了适宜的激素分泌，并增强了RBP4、FGFR2和PGR中的基因表达，因此与高、低组相比，胚胎存活率更高。
