Kidney tissures were collected from 142 calves during a study of pre- and perinatal mortality. Fifty-six calves had oxalate crystals in their renal tissue. Thirty-four of the 56 had either single or multiple congenital defects, mostly of the skeleton. Twenty-two of the 56 died of causes other than congenital defects. The renal oxalosis was more pronounced in those calves affected with congenital anomalies.