General Instructions

Results of serologic tests provide useful information for regulatory and export purposes, and planning herd-health vaccination programs.

For most mammalian cases, a minimum of 2 ml of good quality serum (yellow, clear) is needed for one or more serology tests. Do not freeze blood or allow it to become overheated. Submit serum rather than whole clotted blood if samples will not be received by the laboratory within 48 hours. Blood samples should be collected in sterile tubes containing no anticoagulants (red-top tube). Brucellosis (Bangs) tubes contain residues which may be toxic and thus produce non-diagnostic results.

Serologic results may be of limited use in the diagnosis of infectious diseases unless the results of acute and convalescent sera are compared.  The acute sample should be collected as early in the illness as possible and the convalescent sample two to four weeks later. More definitive results can usually be obtained in less time if samples are submitted for other tests such as bacteriology and virology, at the same time.

For herd situations, submit serum from at least ten (10) animals or 10% of the herd. In the event of special requests or large numbers of samples, please contact the laboratory prior to submission.

Coggins Tests (EIA, Equine Infectious Anemia). Serum must be collected by a licensed, USDA-Accredited veterinarian, and submitted with a signed, fully completed, signed USDA VS Form 10-11. A minimum of 2 working days are required from the time the specimen is received at the laboratory to complete a Coggin’s test; any required supplemental tests require additional times.  

Planning sufficient time for the completion of regulatory serology tests is the responsibility of the owner and veterinarian.  Careful attention to scheduling can prevent stressful situations for proper documentation required to transport of animals to shows, sales, and exhibitions. For information about animal health passports, contact the State Veterinarian