Urolithiasis with uroperitoneum and hydronephrosis in grazing cattlein Southern Brazil

EnglishThe purpose of this paper was to describe obstructive urolithiasis with uroperitoneum and hydronephrosis in range cattle in southern Rio Grande do Sul. The disease was observed in castrated male cattle, aged between 18 months and 3 years in a herd of 200 steers that were in a ryegrass pasture during the winter and a native pasture during the summer. Different mineral salts were used as a supplement for the animals during the two seasons of the year. Cattle presented a progressive abdominal distention, depression and dehydration ranging from 10 days to one month in duration. One animal was necropsied, and approximately 50 liters of urine (uroperitoneum) in the abdominal cavity were observed. The bladder had a small rupture and was adhered to the pelvic cavity. The right kidney was enlarged with hydronephrosis. Uroliths of more than 1cm in diameter were housed in the penile urethra. In this study, the disease occurred probably because of mineral salt supplementation, resulting in an imbalance of calcium and phosphorus intake. Key words: ruminants; uroliths; hydronephrosis portuguesO objetivo deste trabalho foi descrever urolitiase obstrutiva associada a hidroperitonio e hidronefrose em bovinos no sul do Rio Grande do Sul. A doenca foi observada em um rebanho de 200 bovinos machos castrados, com idade entre 18 meses e tres anos, mantidos a campo, que permaneciam no inverno em pastagem de azevem e no verao em campo nativo e eram suplementados com diferentes sais minerais nas duas epocas do ano. Os bovinos afetados apresentavam aumento de volume abdominal progressivo, depressao e desidratacao, com evolucao de 10 dias a um mes. Um bovino foi necropsiado e havia na cavidade abdominal aproximadamente 50 litros de urina (uroperitonio). A bexiga apresentava pequena ruptura e aderencia a cavidade pelvica. O rim direito estava aumentado de tamanho e apresentava hidronefrose. Havia urolitos de mais ou menos 1cm de diâmetro alojados na uretra peniana. Neste caso e provavel que a doenca tenha ocorrido em consequencia da suplementacao com sal mineral contendo quantidades inadequadas de calcio e fosforo levando a um desequilibrio entre estes minerais. Palavras-chaves: ruminantes; urolitos; hidronefrose