Urolithiasis in a captive group of Tammar wallabies (Macropus eugenii).

Urolithiasis is a well-known disease of the urogenital system in domestic animals, and it has also been described in captive and free-ranging wildlife. This article reports 15 cases of urolithiasis in a captive group of Tammar wallabies (Macropus eugenii) between 2004 and 2011. The analyzed stones were composed of pure calcium carbonate (n = 5), calcium carbonate with traces of calcium phosphate (n = 6), carbonate apatite (n = 2), and carbonate apatite mixed with calcium oxalate (n = 2). In 12 out of 15 cases uroliths were situated only in the renal pelvis; in two cases they were found in the renal pelvis and the ureter; while in one case in the ureter only. No common infectious agents were identified either by microbiological or histopathological methods. Although the exact cause remains unknown, the repetitive occurrence of calcium carbonate urolithiasis suggests husbandry-related causes. To the best of the authors' knowledge, this is the first report on recurrent appearance of urolithiasis in a captive group of Tammar wallabies.