Ultrasonographically determined renal values and comparisons to serum biochemistry renal parameters in aged semi-captive cheetahs (Acinonyx jubatus)

Cheetahs in captivity have a high prevalence of chronic renal diseases. Abdominal diagnostic ultrasound is a useful diagnostic modality to evaluate the urinary tract and can give an immediate indication of renal status but lacks sensitivity and specificity for early renal changes in domestic carnivores. We ultrasographically evaluated the renal volumes, a variety of renal dimensions, interarcuate artery resistivity indices as well as aortic diameters and the length of the ventral aspect of the 6th lumbar vertebras in 27 aged semi-captive anesthetized cheetahs. A number of ultrasound ratios were determined to evaluate renal size and the dimensions and ratios were compared to serum creatinine and urea values as well as urine specific gravity. There were minimal differences for all values between left and right kidneys. Mean kidney length was 65 .4 mm (range 54.9-76.9) with left kidney length ratios to L6 length being 1.60 (range1.27-2.06) and to the aortic diameter 7.69 (range 4.54-10.72). Significant correlations between left renal length as well as length:L6 ratio to creatinine values were found ((r -0.66) and (r -0.60) respectively). The mean RI values of the different sedation/anesthetic protocols ranged from 0.46 -0.55. 4 – 0.66. Left renal length and L6 ventral vertebral body length as well as left kidney RI values should be measured in all cheetah abdominal ultrasound examinations. These measurements, together with serum creatinine, urea and urine specific gravity values may be relatively sensitive indicators of early renal pathology in the absence of gross ultrasonographic changes.

圈养中的猎豹普遍存在慢性肾脏疾病。腹部诊断性超声是一种评估泌尿系统的有效诊断手段，能够即时反映肾脏状况，但对于家养肉食动物早期肾脏变化的敏感性和特异性不足。本研究采用超声技术对27只老龄半圈养麻醉猎豹的肾脏体积、多种肾脏尺寸、弓间动脉阻力指数以及主动脉直径和第6腰椎腹侧长度进行了评估。通过一系列超声比值的测定，以评估肾脏大小及其尺寸和比例，并将这些尺寸和比例与血清肌酐、尿素和尿液比重值进行比较。左右肾脏的所有值之间的差异均极小。平均肾脏长度为65.4毫米（范围54.9-76.9），左侧肾脏长度与L6长度的比例为1.60（范围1.27-2.06），与主动脉直径的比例为7.69（范围4.54-10.72）。左侧肾脏长度及其与L6长度的比例与肌酐值之间存在显著的相关性（分别为r-0.66和r-0.60）。不同镇静/麻醉方案的平均阻力指数（RI）值范围为0.46-0.55。在所有猎豹腹部超声检查中，应测量左侧肾脏长度、L6腹侧椎体长度以及左侧肾脏RI值。这些测量值，连同血清肌酐、尿素和尿液比重值，可能是在未出现明显超声变化的情况下，对早期肾脏病理变化的相对敏感指标。