Comparative Ultrasound Features of the Liver, Kidneys and Spleen in Female Sheep (Ovis aries) at Different Ages

摘要

To determine whether there are variations in ultrasound features of different organs between sheep of different ages, 16 apparently healthy mixed breed female sheep (Ovis aries), 6 mo to 8 yr old, were distributed into four age groups. Ultrasound examination was performed in non-sedated sheep in standing position using an ultrasound machine equipped with a 3.5 MHz convex array transducer. The liver, kidneys and spleen were examined, ultrasound images were recorded using a video graphic printer and measurements were done using the ultrasound machine electronic caliper. The acoustic window for the liver, kidneys and spleen was similar for all age groups. No difference was observed in liver echogenicity, appearance of gall bladder, and portal and hepatic veins among age groups. No differences in echogenicities of the renal structures were observed. Renal dimensions such as width, thickness and length of the left and right kidneys increased with increasing age. However, no differences were observed inthe thickness of the capsule, cortex, medulla and sinus between the different age groups. No differences in ultrasound features of the different structures of the spleen between different ages were observed. No significant differences were observed between the splenic dimensions of the animals at different ages. The results of the study suggest that from the age of six mo up to eight yr old, ultrasonography of the liver, kidneys and spleen can be performed for diagnosis of disorders without consideration of the age of the sheep.