Petersson K H, Warner R G, Kallfelz F A, Crosetti C F
Department of Animal Science, Cornell University, Ithaca, NY 14853.
J Dairy Sci. 1988 Dec;71(12):3369-77. doi: 10.3168/jds.S0022-0302(88)79942-7.
Forty veal calves were fed milk replacers containing differing concentrations of Mg in a 16-w study. The concentrations were .1% (basal), .3%, .6% Mg, and .6% Mg plus 2% NaCl. The four groups were further subdivided into two groups fed reconstituted milk replacer at 14 or 17.9% DM. Weight gain was greater at the two lower concentrations of Mg. Calves fed .6% Mg or .6% Mg plus NaCl excreted significantly more Mg than calves fed .1 or .3% magnesium. The low water group (17.9% DM) excreted a more concentrated urine relative to Mg, Ca, and P than did the high water group (14% DM). No urethral obstructions were observed. Seventy percent of calves at .6% Mg and 30% of calves at .6% Mg plus NaCl had stones in their kidneys consisting primarily of calcium apatite and secondarily of struvite. Added NaCl reduced kidney and bladder calculi formation. When high amounts of water were fed, added NaCl prevented calculi formation completely. All calves fed the NRC level of .1% Mg performed normally.
在一项为期16周的研究中，40头小牛肉牛犊被喂食了含有不同镁浓度的代乳粉。这些浓度分别为0.1%（基础浓度）、0.3%、0.6%的镁，以及0.6%的镁加2%的氯化钠。这四组又进一步细分为两组，分别喂食干物质含量为14%或17.9%的复水代乳粉。较低的两种镁浓度下体重增加更多。喂食0.6%镁或0.6%镁加氯化钠的牛犊排出的镁明显多于喂食0.1%或0.3%镁的牛犊。低水分组（17.9%干物质）相对于高水分组（14%干物质）排出的尿液中镁、钙和磷的浓度更高。未观察到尿道梗阻。6%镁组70%的牛犊和6%镁加氯化钠组30%的牛犊肾脏中有结石，主要由磷酸钙组成，其次为鸟粪石。添加氯化钠可减少肾脏和膀胱结石的形成。当喂食大量水分时，添加氯化钠可完全防止结石形成。所有喂食美国国家研究委员会（NRC）规定的0.1%镁水平的牛犊表现正常。
