Men Zhaoyue, Cao Meng, Gong Yuechan, Hua Lun, Zhang Ruihao, Zhu Xin, Tang Lianchao, Jiang Xuemei, Xu Shengyu, Li Jian, Che Lianqiang, Lin Yan, Feng Bin, Fang Zhengfeng, Wu De, Zhuo Yong
Animal Nutrition Institute, Sichuan Agricultural University, 211 Huimin Road, Wenjiang District, Chengdu, 611130, People's Republic of China.
College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, 611130, People's Republic of China.
J Anim Sci Biotechnol. 2022 Jan 13;13(1):14. doi: 10.1186/s40104-021-00657-0.
Dietary fiber (DF) is often eschewed in swine diet due to its anti-nutritional effects, but DF is attracting growing attention for its reproductive benefits. The objective of this study was to investigate the effects of DF intake level on oocyte maturation and uterine development, to determine the optimal DF intake for gilts, and gain microbial and metabolomic insight into the underlying mechanisms involved.
Seventy-six Landrace × Yorkshire (LY) crossbred replacement gilts of similar age (92.6 ± 0.6 d; mean ± standard deviation [SD]) and body weight (BW, 33.8 ± 3.9 kg; mean ± SD) were randomly allocated to 4 dietary treatment groups (n = 19); a basal diet without extra DF intake (DF 1.0), and 3 dietary groups ingesting an extra 50% (DF 1.5), 75% (DF 1.75), and 100% (DF 2.0) dietary fiber mixture consisting of inulin and cellulose (1:4). Oocyte maturation and uterine development were assessed on 19 d of the 2nd oestrous cycle. Microbial diversity of faecal samples was analysed by high-throughput pyrosequencing (16S rRNA) and blood samples were subjected to untargeted metabolomics.
The rates of oocytes showing first polar bodies after in vitro maturation for 44 h and uterine development increased linearly with increasing DF intake; DF 1.75 gilts had a 19.8% faster oocyte maturation rate and a 48.9 cm longer uterus than DF 1.0 gilts (P < 0.05). Among the top 10 microbiota components at the phylum level, 8 increased linearly with increasing DF level, and the relative abundance of 30 of 53 microbiota components at the genus level (> 0.1%) increased linearly or quadratically with increasing DF intake. Untargeted metabolic analysis revealed significant changes in serum metabolites that were closely associated with microbiota, including serotonin, a gut-derived signal that stimulates oocyte maturation.
The findings provide evidence of the benefits of increased DF intake by supplementing inulin and cellulose on oocyte maturation and uterine development in gilts, and new microbial and metabolomic insight into the mechanisms mediating the effects of DF on reproductive performance of replacement gilts.
膳食纤维（DF）由于其抗营养作用，在猪的日粮中常被摒弃，但DF因其对繁殖的益处而越来越受到关注。本研究的目的是调查DF摄入量对卵母细胞成熟和子宫发育的影响，确定后备母猪的最佳DF摄入量，并从微生物和代谢组学角度深入了解其潜在机制。
将76头年龄相近（92.6±0.6天；平均值±标准差[SD]）、体重相近（BW，33.8±3.9千克；平均值±SD）的长白×大白（LY）杂交后备母猪随机分为4个日粮处理组（n = 19）；一个不额外摄入DF的基础日粮组（DF 1.0），以及3个分别额外摄入50%（DF 1.5）、75%（DF 1.75）和100%（DF 2.0）由菊粉和纤维素（1:4）组成的膳食纤维混合物的日粮组。在第2个发情周期的第19天评估卵母细胞成熟和子宫发育情况。通过高通量焦磷酸测序（16S rRNA）分析粪便样本的微生物多样性，并对血液样本进行非靶向代谢组学分析。
体外成熟44小时后出现第一极体的卵母细胞比例和子宫发育情况随DF摄入量的增加呈线性增加；DF 1.75组的后备母猪卵母细胞成熟率比DF 1.0组快19.8%，子宫长度比DF 1.0组长48.9厘米（P < 0.05）。在门水平的前10种微生物群落成分中，8种随DF水平的增加呈线性增加，在属水平的53种微生物群落成分中（> 0.1%），30种的相对丰度随DF摄入量的增加呈线性或二次方增加。非靶向代谢分析显示血清代谢物有显著变化，这些变化与微生物群落密切相关，包括血清素，一种刺激卵母细胞成熟的肠道衍生信号。
研究结果证明了通过补充菊粉和纤维素增加DF摄入量对后备母猪卵母细胞成熟和子宫发育有益，并从微生物和代谢组学角度对介导DF对后备母猪繁殖性能影响的机制有了新的认识。
