Severe renal oxalosis in five young Beefmaster calves.

Severe renal oxalosis was diagnosed in 4 male and 1 female purebred Beefmaster calves from herds in southeastern and northwestern United States. Clinical signs included weakness, anorexia, lethargy, alopecia, dehydration, and diarrhea. Results of serum biochemical analysis for 2 calves were consistent with end-stage renal disease. Calves died 2 days to 6 weeks after birth. At necropsy, renal calyces were dilated and contained pale yellow granular calculi. Histologically, there was renal interstitial fibrosis, and cortical and medullary tubules were distended with calcium oxalate crystals. Oxalate crystals were also in the tracheal glands of 1 calf. Severe renal oxalosis in young purebred calves, on widely varied diets, with no known exposure to exogenous oxalates is suggestive of an inherited metabolic defect resulting in primary hyperoxaluria.