Norris C R, Christopher M M, Howard K A, Nelson R W
Veterinary Medical Teaching Hospital, School of Veterinary Medicine, University of California, Davis 95616, USA.
Am J Vet Res. 1999 Sep;60(9):1159-63.
To evaluate the efficacy of using serum total and ionized magnesium (Mg) concentrations and urine Mg concentrations to identify Mg deficiency in cats.
6 healthy castrated male cats.
A Mg-replete diet was fed for 37 days, followed by a Mg-deficient diet for 37 days. On days 1, 3, and 7 of the last week of each diet, serum ionized and total Mg concentrations were determined; in addition, urine Mg concentration was determined each day of the last week. Serum total and ionized Mg concentrations were compared with urine Mg concentration, amount of Mg excreted during 24 hours (24-hour urine Mg excretion), ratio of urine Mg concentration to urine creatinine concentration (Umg:Ucr), and urinary fractional excretion of Mg (FEmg) to determine which variable best predicted Mg status.
Cats fed Mg-deficient diets had significantly lower serum total and ionized Mg concentrations and 24-hour urine Mg excretion values, compared with cats fed Mg-replete diets. Serum total Mg concentration was the best predictor of Mg status. Twenty-four-hour urine Mg excretion was a repeatable, reliable measurement and had the best correlation with serum total Mg concentration. Serum total Mg concentration also correlated with urine Mg concentration, Umg:Ucr, and FEmg.
Serum total and ionized Mg concentrations can be used to identify cats with dietary-induced Mg deficiencies. Twenty-four-hour urine Mg excretion and urine Mg concentration correlated best with serum total Mg concentration and, therefore, may be the most useful urine variables for identifying Mg deficiency.
评估利用血清总镁和离子镁浓度以及尿镁浓度来识别猫镁缺乏的有效性。
6只健康去势雄猫。
先给予富含镁的饮食37天，随后给予缺镁饮食37天。在每种饮食最后一周的第1天、第3天和第7天，测定血清离子镁和总镁浓度；此外，在最后一周的每一天测定尿镁浓度。将血清总镁和离子镁浓度与尿镁浓度、24小时镁排泄量（24小时尿镁排泄）、尿镁浓度与尿肌酐浓度之比（Umg:Ucr）以及尿镁分数排泄率（FEmg）进行比较，以确定哪个变量最能预测镁状态。
与喂食富含镁饮食的猫相比，喂食缺镁饮食的猫血清总镁和离子镁浓度以及24小时尿镁排泄值显著降低。血清总镁浓度是镁状态的最佳预测指标。24小时尿镁排泄是一种可重复、可靠的测量方法，与血清总镁浓度的相关性最佳。血清总镁浓度也与尿镁浓度、Umg:Ucr和FEmg相关。
血清总镁和离子镁浓度可用于识别因饮食导致镁缺乏的猫。24小时尿镁排泄和尿镁浓度与血清总镁浓度的相关性最佳，因此可能是识别镁缺乏最有用的尿液变量。
