Urinary retention in two male dromedaries due to silica uroliths

Two cases of urinary retention in male dromedaries due to silica uroliths a re presented. The animals were urethrostomized and one dromedary was euthan ized 7 months later due to urethrostomy obstruction. The estimated daily in take of silica was 84.44 g. Silica, calcium, phosphorus and pH in urine mer e determined in healthy animals from the same farms, and the following valu es were obtained: 174.78 +/- 3.46 mg/l (silica), 41.48 +/- 4.82 mg/l (calci um), 20.4 +/- 3.6 mg/l (phosphorus) and pH 8.2, respectively. Possible caus es of urolithiasis were the early castration of the animals and the fact th at salt was not added to the diet. To our knowledge, this is the first desc ription of silica urolithiasis in the dromedary camel.