Teh T H, Hemken R W, Harmon R J
J Dairy Sci. 1985 Apr;68(4):881-90. doi: 10.3168/jds.S0022-0302(85)80905-X.
Thirty-six Holstein cows were fed a diet of 50% concentrate and 50% corn silage (dry matter) for 12 wk postpartum. Treatments were 0, .4, and .8% magnesium oxide with or without .8% sodium bicarbonate in a 2 X 3 factorial arrangement. Dry matter intake was not different among treatments although the combined buffers had higher intake. Milk production was higher for the .4% magnesium oxide treatments either alone or with sodium bicarbonate as compared with either the 0 or .8% magnesium oxide treatments. Ruminal pH was increased with addition of sodium bicarbonate either alone or together with magnesium oxide. Dietary addition of .4% magnesium oxide either alone or with sodium bicarbonate increased total volatile fatty acid in ruminal fluid. Propionate and valerate were depressed in both of the combined buffered diets. Fecal pH was increased with magnesium oxide addition either alone or with sodium bicarbonate. Increasing magnesium oxide increased magnesium in plasma. No interactions in animal performance were significant for the two buffers.
36头荷斯坦奶牛在产后12周饲喂由50%精饲料和50%玉米青贮料（干物质）组成的日粮。处理方式采用2×3析因设计，分别为添加0%、0.4%和0.8%的氧化镁，且添加或不添加0.8%的碳酸氢钠。尽管复合缓冲剂组的干物质采食量较高，但各处理组之间的干物质采食量并无差异。与添加0%或0.8%氧化镁的处理组相比，单独添加0.4%氧化镁或同时添加0.4%氧化镁和碳酸氢钠的处理组产奶量更高。单独添加碳酸氢钠或同时添加碳酸氢钠和氧化镁均可提高瘤胃液pH值。日粮中单独添加0.4%氧化镁或同时添加0.4%氧化镁和碳酸氢钠均可提高瘤胃液中总挥发性脂肪酸的含量。两种复合缓冲日粮中的丙酸和戊酸含量均降低。单独添加氧化镁或同时添加氧化镁和碳酸氢钠均可提高粪便pH值。增加氧化镁的添加量可提高血浆中的镁含量。两种缓冲剂对动物生产性能的影响无显著交互作用。
