While many aspects of animal health are highly regulated, that’s not the case for all types of diagnostic testing. There are standards in place for testing prescribed by USDA and state authorities, but that’s only a small fraction of the testing done in diagnostic labs. Dr. Bruce Akey, a veterinarian and director of the Texas A&M Veterinary Medical Diagnostic Laboratory, says there are no national regulations for conducting and interpreting other diagnostic tests, which can lead to variation.