State Key Laboratory of Animal Nutrition,College of Animal Science and Technology,China Agricultural University,Beijing 100193,P. R. China.
Animal. 2018 Nov;12(11):2284-2291. doi: 10.1017/S1751731118000289. Epub 2018 Feb 26.
In the present study, calcium propionate (CaP) was used as feed additive in the diet of calves to investigate their effects on rumen fermentation and the development of rumen epithelium in calves. To elucidate the mechanism in which CaP improves development of calf rumen epithelium via stimulating the messenger RNA (mRNA) expression of G protein-coupled receptors, a total of 54 male Jersey calves (age=7±1 days, BW=23.1±1.2 kg) were randomly divided into three treatment groups: control without CaP supplementation (Con), 5% CaP supplementation (5% CaP) and 10% CaP supplementation (10% CaP). The experiment lasted 160 days and was divided into three feeding stages: Stage 1 (days 0 to 30), Stage 2 (days 31 to 90) and Stage 3 (days 91 to 160). Calcium propionate supplementation percentages were calculated on a dry matter basis. In total, six calves from each group were randomly selected and slaughtered on days 30, 90 and 160 at the conclusion of each experimental feeding stage. Rumen fermentation was improved with increasing concentration of CaP supplementation in calves through the first 30 days (Stage 1). No effects of CaP supplementation were observed on rumen fermentation in calves during Stage 2 (days 31 to 90). Supplementation with 5% CaP increased propionate concentration, but not acetate and butyrate in calves during Stage 3 (days 91 to 160). The rumen papillae length of calves in the 5% CaP supplementation group was greater than that of Con groups in calves after 160 days feeding. The mRNA expression of G protein-coupled receptor 41 (GPR41) and GPR43 supplemented with 5% CaP were greater than the control group and 10% CaP group in feeding 160 days calves. 5% CaP supplementation increased the mRNA expression of cyclin D1, whereas did not increase the mRNA expression of cyclin-dependent kinase 4 compared with the control group in feeding 160-day calves. These results indicate that propionate may act as a signaling molecule to improve rumen epithelium development through stimulating mRNA expression of GPR41 and GPR43.
在本研究中，丙酸钙（CaP）被用作小牛饲料中的添加剂，以研究其对瘤胃发酵和小牛瘤胃上皮发育的影响。为了阐明 CaP 通过刺激 G 蛋白偶联受体的信使 RNA（mRNA）表达来改善小牛瘤胃上皮发育的机制，总共将 54 头雄性泽西奶牛（年龄=7±1 天，BW=23.1±1.2kg）随机分为三组：对照组（无 CaP 补充）（Con）、5%CaP 补充（5%CaP）和 10%CaP 补充（10%CaP）。实验持续 160 天，分为三个喂养阶段：阶段 1（0 至 30 天）、阶段 2（31 至 90 天）和阶段 3（91 至 160 天）。丙酸钙的补充量是基于干物质计算的。每组共随机选择 6 头小牛，在每个实验喂养阶段结束时的第 30、90 和 160 天进行屠宰。通过前 30 天（第 1 阶段），随着 CaP 补充浓度的增加，小牛的瘤胃发酵得到改善。在第 2 阶段（31 至 90 天），CaP 补充对小牛的瘤胃发酵没有影响。在第 3 阶段（91 至 160 天），5%CaP 补充增加了丙酸的浓度，但不增加乙酸和丁酸在小牛中的浓度。在 160 天喂养后，5%CaP 补充组的小牛瘤胃乳头长度大于对照组。在 160 天喂养的小牛中，与对照组和 10%CaP 组相比，添加 5%CaP 的 G 蛋白偶联受体 41（GPR41）和 GPR43 的 mRNA 表达更高。5%CaP 补充增加了 cyclin D1 的 mRNA 表达，而与对照组相比，cyclin D1 的 mRNA 表达没有增加。依赖性激酶 4（CDK4）在 160 天喂养的小牛中。这些结果表明，丙酸可能作为一种信号分子，通过刺激 GPR41 和 GPR43 的 mRNA 表达来改善瘤胃上皮的发育。
