Radiographic Estimation of the Location and Size of kidneys in Nigerian local dogs

Abstract

Keywords: Radiography, Location, Kidney size, Local dogs The kidneys of dogs and cats are located retroperitoneally (Bjorling, 1993). Visualization of the kidneys on radiographs is possible due to the contrast provided by the perirenal fat (Grandage, 1975). However, this perirenal fat rarely covers the ventral surface of the kidney and are absent in lean dogs. Thus interpretation of abnormality on survey radiograph is based on a good knowledge of the radiological anatomy of the kidney (Brodsky, et al., 1977). This knowledge include the sizes and locations of the kidneys. Reports on exotic breeds revealed that the right kidney is located between the last thoracic (T13) and second lumbar (L2) vertebrae while the left kidney is located between the first Lumbar (L1) and the third Lumbar (L3) vertebrae (Finco, et al., 1971; Osborne and Fletcher, 1995). However, to date, there is no report on the radiological parameters of the kidney of the local dogs. This study was therefore carried out to establish the length, width and location of both kidneys in local dogs. Ten local dogs comprising of 8 non-lactating non-pregnant bitches and 2 intact male dogs with an average weight of 10.7+1.2kg were used for this study. They were judged to be in good general health and with no kidney abnormality based on the results of complete physical examination, serum creatinine and urinalysis of urine samples obtained by cystocentesis. Prior to radiography, the dogs were fasted overnight and saline enema administered to empty the colorectum of feaces. They were sedated for radiography using atropine and 2% xylazine (Chanazine, Chanelle pharmaceuticals) at the intramuscular dosage rates of 0.04mg/kg and 2.0mg/kg, respectively. In order to improve the opacification of the kidney for proper visualization, 76% urograffin (Schering pharmaceuticals) was administered intravenously through the cephalic vein at the dosage rate of 800mg/kg (Morgan and Silverman, 1983). Ventrodorsal abdominal radiograph of the dog was then obtained immediately after the injection of urograffin. The location, length and width of the left and right kidneys were determined from each radiograph. Both the length and width were measured in relation to the length of the second lumbar vertebrae (L2). The length of the kidney was taken as the distance between the cranial and caudal poles while the width was taken as the diameter from the hilus to the capsule on the opposite side. The means of the length and width, of the right and left Trop. Vet. Vol. 20(3) 2002: 169-171