Final answer:
The distance between the two injection sites in the SICCT test is 4 centimeters. This spacing is important for the accuracy of the test in detecting bovine tuberculosis in cattle.
Step-by-step explanation:
The distance between the two injection sites in the Single Intradermal Comparative Cervical Tuberculin (SICCT) test is 4 centimeters. The SICCT test is a diagnostic procedure used in veterinary medicine, particularly in cattle, to detect the presence of bovine tuberculosis. It is critical to maintain the recommended distance to ensure the accuracy of the test results, as it allows for sufficient space between the two intradermal injections of tuberculin.