Urolithiasis is a common disease in the Brazilian semiarid in rams and bucks fed with grains, mainly with low C:P ratio. From 28 rams with urolithiasis sent to the Veterinary Hospital of the Federal University of Campina Grande, Paraíba, 19 died and 9 survived, and from the bucks, 13 died and 3 survived At necropsy the main lesions were presence of calculi in the urethra and urinary bladder, diffuse purulent urethritis, hemorrhagic necrotizing urethritis, rupture of the urethra with presence of urine in the subcutaneous tissue, hydronephrosis, urinary bladder rupture, necrotizing diffuse nephritis, pyelonephritis, renal hemorrhage, and renal rupture. The severity of the lesions is responsible for the high case fatality rate despite medical and chirurgic treatment. The most important preventive measure is the correction of the Ca:P ratio to at least 2:1. The administration of good quality roughage in the food is also necessary. In cases in which the amount of concentrate food is higher than 1.5% live weight, the addition of 1% ammonium chloride and 0.5-4% of sodium chloride in the diet could be also necessary. Water had to be offered ad libitum. It is necessary to abolish the use of ad libitum mineral supplementation in sheep and goats fed grains or their byproducts.
Urolithiasis; grain feeding; phosphorous; phosphorus:calcium rate