One hundred Yorkshire × Landrace sows were randomly assigned to one of two dietary treatments (diet ND: 6,000 IU vitamin D₃/d feed; diet 25‐D: 200 μg/day 25OHD₃ feed). The experiment began on d 90 of gestation and continued until weaning on day 21 of lactation. In sows that received 25OHD₃, the growth rate of the piglets before weaning was significantly accelerated (0.266 kg/day, p  < .05). Sow serum was collected after weaning, and those in the 25OHD₃ group were found to have significantly higher serum calcium (CA) and phosphorus (PI) levels (p  < .05). Interestingly, the oestrus cycle of sows fed 25OHD₃ was significantly shortened (p  < .05), the oestrus time was concentrated on the fifth day after weaning, and the piglets were born with a higher degree of uniformity (p  < .05). Colostrum was collected on the day of delivery, and the colostrum of sows fed 25OHD₃ contained higher milk fat content than the control group (p  < .05). 25OHD₃ supplementation increased the mRNA and protein expression of INSIG1 and SREBP1, which regulate milk fat synthesis, in the mammary gland of lactating sows (p  < .05). In conclusion, 25OHD₃ supplementation in maternal diets improved reproductive performance, milk fat content and the mRNA and protein levels of genes regulating milk fat synthesis in lactating sows.

中文翻译：

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母体日粮中添加 25-羟基胆钙化醇对母猪繁殖性能和调节泌乳基因表达的影响。

100 头约克夏 × 长白母猪被随机分配到两种日粮处理中的一种（日粮 ND：6,000 IU 维生素 D ₃ /d 饲料；日粮 25-D：200 μg/天 25OHD ₃饲料）。实验从妊娠第 90 天开始，一直持续到哺乳期第 21 天断奶。在接受 25OHD _{3 的}母猪中，断奶前仔猪的生长速度显着加快（0.266 公斤/天，p  < .05）。断奶后收集母猪血清，发现 25OHD ₃组的母猪血清钙 (CA) 和磷 (PI) 水平显着升高 ( p  < .05)。_{有趣的是，饲喂 25OHD 3}的母猪发情周期显着缩短（p < .05)，发情时间集中在断奶后第 5 天，仔猪出生均匀度较高 ( p  < .05)。初乳是在分娩当天收集的，饲喂 25OHD ₃的母猪初乳中的乳脂含量高于对照组 ( p  < .05)。添加25OHD ₃增加了泌乳母猪乳腺中调节乳脂合成的INSIG1和SREBP1的 mRNA 和蛋白质表达( p  < .05)。总之，25OHD ₃母体日粮中的补充剂改善了繁殖性能、乳脂含量以及调节泌乳母猪乳脂合成的基因的 mRNA 和蛋白质水平。