Ministry of Education Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, P. R. China.
Anim Biotechnol. 2022 Apr;33(2):289-296. doi: 10.1080/10495398.2020.1806073. Epub 2020 Aug 18.
The aim of the present study was to evaluate how long-term high-concentrate diet feeding affected rumen epithelium (RE) of dairy cows. So, 12 mid-lactating multiparous cows were divided into two groups randomly fed either with high-concentrate diet (HC, concentrate: forage = 6: 4) or low-concentrate diet (LC, concentrate: forage = 4:6) for 20 weeks. Remarkable upregulation of lipopolysaccharide (LPS) level and depress of pH in rumen fluid were induced by HC compared with LC group. mRNA abundance of (), (), (), , and were elevated in RE of HC group compared with LC group. Greater protein abundance of phosphorylated NF-κB p65, IL-6, and tumor necrosis factor α (TNF-α) was observed in RE of cows fed HC than that fed LC. Abundance of protein related to proapoptotic response (cytochrome c, BAX and caspase-3) in HC group was greater than that in LC group, while the abundance of anti-apoptotic factor protein (Bcl-2) was lower in HC group than LC group. Therefore, the present study demonstrated that long-term high-concentrate diet feeding upregulated LPS level in rumen fluid and induced the proinflammatory response in the rumen epithelium and apoptosis of rumen epithelial cells.
本研究旨在评估长期高浓度日粮喂养如何影响奶牛的瘤胃上皮（RE）。因此，将 12 头泌乳中期的经产奶牛随机分为两组，分别用高浓度日粮（HC，精料：粗饲料=6:4）和低浓度日粮（LC，精料：粗饲料=4:6）喂养 20 周。与 LC 组相比，HC 组的瘤胃液中脂多糖（LPS）水平显著上调，pH 值降低。与 LC 组相比，HC 组 RE 中（）、（）、（）、、和的 mRNA 丰度升高。与 LC 组相比，HC 组奶牛 RE 中磷酸化 NF-κB p65、IL-6 和肿瘤坏死因子-α（TNF-α）的蛋白丰度更高。与 LC 组相比，HC 组促凋亡反应相关蛋白（细胞色素 c、BAX 和 caspase-3）的蛋白丰度更高，而抗凋亡因子蛋白（Bcl-2）的丰度更低。因此，本研究表明，长期高浓度日粮喂养会增加瘤胃液中的 LPS 水平，并在瘤胃上皮引起促炎反应和瘤胃上皮细胞凋亡。
