Rolling Rock Mastiffs follows health testing guidelines before we will consider breeding.  Our mastiffs are clear of hip and elbow dysplasia.  We have their heart and patella's checked to make sure they are normal.  In addition, their eyes are CERF'ed & PRA DNA tested.  Our mastiffs are also tested clear of VWD, Cystinuria and thyroid disease.  Unfortunately, problems do occur in every breed of dog.  By using these guidelines we hope to improve the breed and eliminate the crippling and painful problems that hurt our pets and the families hearts.