Waltham Centre for Pet Nutrition, Freeby Lane, Waltham-on-the-Wolds, Melton Mowbray, Leicestershire LE14 4RT, UK.
Br J Nutr. 2011 Oct;106 Suppl 1:S128-30. doi: 10.1017/S0007114511001875.
It has been reported that daily fluid intake influences urinary dilution, and consequently the risk of urolithiasis in human subjects and dogs. The aim of the present study was to investigate the role of dietary moisture on urinary parameters in healthy adult cats by comparing nutritionally standardised diets, varying only in moisture content. A total of six cats were fed a complete dry food (6.3 % moisture) hydrated to 25.4, 53.2 and 73.3 % moisture for 3 weeks in a randomised block cross-over design. Urinary specific gravity (SG), urine volume, water drunk and total fluid intake were measured daily; relative supersaturation (RSS) for calcium oxalate (CaOx) and struvite was calculated using the SUPERSAT computer program. Cats fed the 73.3 % moisture diet produced urine with a significantly lower SG (P < 0.001) compared with diets containing 53.2 % moisture or lower. Mean RSS for CaOx was approaching the undersaturated zone (1.14 (sem 0.21); P = 0.001) for cats fed the diet with 73.3 % moisture and significantly lower than the 6.3 % moisture diet (CaOx RSS 2.29 (sem 0.21)). The effect of diet on struvite RSS was less clear, with no significant difference between treatment groups. Total fluid intake was significantly increased (P < 0.001) in the 73.3 % moisture diet (144.7 (SEM 5.2) ml, or 30 ml/kg body weight per d) compared with the 6.3 % (103.4 (SEM 5.3) ml), 25.4 % (98.6 (SEM 5.3) ml) and 53.3 % (104.7 (SEM 5.3) ml) moisture diets, despite voluntary water intake decreasing as dietary moisture intake increased. Cats fed the 73.3 % moisture diet had a higher total daily fluid intake resulting in a more dilute urine with a lower risk of CaOx when compared with the lower-moisture diets.
据报道，每日液体摄入量会影响尿液稀释度，从而影响人类和犬类的尿路结石风险。本研究旨在通过比较仅在水分含量上有所不同的营养标准化饮食，来研究饮食水分对健康成年猫尿液参数的作用。总共 6 只猫随机分组进行交叉设计，分别喂食完全干燥的食物（含水量为 6.3%），并分别将其水分含量调整至 25.4%、53.2%和 73.3%，持续 3 周。每天测量尿液比重（SG）、尿量、饮水量和总液体摄入量；使用 SUPERSAT 计算机程序计算钙草酸（CaOx）和鸟粪石的相对过饱和度（RSS）。与含水量为 53.2%或更低的饮食相比，喂食 73.3%水分饮食的猫产生的尿液 SG 显著降低（P < 0.001）。喂食 73.3%水分饮食的猫的 CaOx RSS 接近过饱和区（1.14（sem 0.21）；P = 0.001），明显低于 6.3%水分饮食（CaOx RSS 2.29（sem 0.21））。饮食对鸟粪石 RSS 的影响不太明显，各组之间无显著差异。73.3%水分饮食组的总液体摄入量显著增加（P < 0.001）（144.7（SEM 5.2）ml，或 30 ml/kg 体重/天），与 6.3%（103.4（SEM 5.3）ml）、25.4%（98.6（SEM 5.3）ml）和 53.3%（104.7（SEM 5.3）ml）水分饮食相比，尽管随着饮食水分摄入的增加，自愿饮水量减少。与低水分饮食相比，喂食 73.3%水分饮食的猫总液体日摄入量更高，导致尿液更稀释，CaOx 形成风险更低。
