Funaba Masayuki, Yamate Takayo, Hashida Yuka, Maki Kodenta, Gotoh Ken, Kaneko Masahiro, Yamamoto Hiromi, Iriki Tsunenori, Hatano Yoshikazu, Abe Matanobu
Laboratory of Nutrition, Azabu University School of Veterinary Medicine, 1-17-71 Fuchinobe, Sagamihara 229-8501, Japan.
Am J Vet Res. 2003 Aug;64(8):1059-64. doi: 10.2460/ajvr.2003.64.1059.
To evaluate the effects of a high-protein diet versus dietary supplementation with ammonium chloride (NH4Cl) on struvite crystal formation in the urine of clinically normal cats by measuring the urine concentration of hydrochloric acid (HCl)-insoluble sediment, urine pH, struvite activity product (SAP), number of struvite crystals in urine, and urine volume.
23 healthy adult cats.
Urine was fractionated by centrifugation with subsequent extraction of the sediment with 1 N HCl (study 1). Diets containing either 29% crude protein or 55% crude protein were fed to cats in a crossover trial of 3 weeks/period (study 2). Diets supplemented with either sodium chloride (NaCl) or NH4Cl were fed, by use of a 3 x 3 Latin-square design with 3 wk/period (study 3). In studies 2 and 3, urine samples were collected for the last 7 days of each period.
The HCl-insoluble sediment contained Tamm-Horsfall glycoprotein (THP; study 1). The high-protein diet (study 2) and dietary supplementation with NH4Cl (study 3) resulted in a decrease in urine pH, SAP, and the number of struvite crystals in urine. However, the high-protein diet decreased urine concentrations of HCl-insoluble sediment containing THP (study 2), in contrast to the NH4Cl supplementation that increased urine volume without a significant effect on the urine concentration of the HCl-insoluble sediment (study 3).
Our results indicate that compared with dietary supplementation with NH4Cl, the high-protein diet is preferable as a urine acidifier for the prevention of struvite crystal formation in clinically normal cats.
通过测量盐酸（HCl）不溶性沉淀物的尿液浓度、尿液pH值、鸟粪石活性产物（SAP）、尿液中鸟粪石晶体数量和尿量，评估高蛋白饮食与氯化铵（NH4Cl）膳食补充剂对临床正常猫尿液中鸟粪石晶体形成的影响。
23只健康成年猫。
通过离心对尿液进行分级分离，随后用1N HCl提取沉淀物（研究1）。在为期3周/周期的交叉试验中，给猫喂食含29%粗蛋白或55%粗蛋白的饮食（研究2）。采用3×3拉丁方设计，为期3周/周期，给猫喂食补充氯化钠（NaCl）或NH4Cl的饮食（研究3）。在研究2和3中，在每个周期的最后7天收集尿液样本。
HCl不溶性沉淀物含有Tamm-Horsfall糖蛋白（THP；研究1）。高蛋白饮食（研究2）和NH4Cl膳食补充剂（研究3）导致尿液pH值、SAP和尿液中鸟粪石晶体数量减少。然而，高蛋白饮食降低了含THP的HCl不溶性沉淀物的尿液浓度（研究2），与之形成对比的是，NH4Cl补充剂增加了尿量，但对HCl不溶性沉淀物的尿液浓度没有显著影响（研究3）。
我们的结果表明，与NH4Cl膳食补充剂相比，高蛋白饮食作为尿液酸化剂更适合预防临床正常猫的鸟粪石晶体形成。
