Eriksson L, Valtonen M, Mäkelä J
Acta Physiol Scand Suppl. 1984;537:59-64.
The effect of a ten-day dietary sodium load on the fluid balance of mink was studied by adding to the food NaCl 0.5, 1 or 2% of the wet weight. The basic diet without salt addition contained sodium corresponding to 0.5% NaCl of the wet weight. The animals showed no signs of discomfort, eating well in all test groups. Adding of 0.5% salt to the food did not increase drinking of water, whereas 1 and 2% salt addition doubled and quadrupled water consumption, respectively. Urine excretion was slightly higher than consumption of drinking water, and both increased parallelly to increasing salt intake. The dietary salt excess was mainly excreted in urine, whereas the alimentary canal played only a minor role. Urine sodium concentration rose with increasing salt intake, peak concentration 350 mM being reached in the diet with 1% salt addition. On higher sodium load any further increase in renal sodium excretion was achieved only by increasing the volume of urine. Urine osmolality was slightly above 2000 mOsm/kg on the control diet and on the diet with 0.5% salt addition. More diluted urine was excreted on higher salt loads, urine osmolality being 1500 mOsm/kg on the diet with 2% salt addition. Healthy minks appear to tolerate considerably high concentrations of salt in the feed. However, a sufficient supply of drinking water is of critical importance, because increased water intake and renal sodium excretion are the main means of eliminating excess salt.
通过在食物中添加占湿重0.5%、1%或2%的氯化钠，研究了为期十天的饮食钠负荷对水貂体液平衡的影响。不添加盐的基础饮食所含钠相当于湿重0.5%的氯化钠。所有试验组的动物均未表现出不适迹象，进食良好。在食物中添加0.5%的盐不会增加水的摄入量，而添加1%和2%的盐会使水的消耗量分别增加一倍和四倍。尿液排泄量略高于饮水量，二者均随盐摄入量的增加而平行增加。饮食中多余的盐主要通过尿液排出，而消化道的作用较小。尿液钠浓度随盐摄入量的增加而升高，在添加1%盐的饮食中达到峰值浓度350 mM。在更高的钠负荷下，只有通过增加尿量才能进一步增加肾脏钠排泄。对照饮食和添加0.5%盐的饮食中，尿渗透压略高于2000 mOsm/kg。在更高的盐负荷下，排出的尿液更稀，添加2%盐的饮食中尿渗透压为1500 mOsm/kg。健康的水貂似乎能耐受饲料中相当高浓度的盐。然而，充足的饮水供应至关重要，因为增加水的摄入量和肾脏钠排泄是消除多余盐分的主要方式。
