The quality of the tests and their interpretation is primarily dependent upon the quality of the submitted material. Keep the following important factors in mind when submitting samples.
- Sampling prior to therapy is vital to the reliability of all types of samples.
- Submission of a complete clinical history including physical examination findings, current medication, and time and date of obtaining the sample from the patient.
- Submission of volumes in excess of requirement is ideal as it enables further investigation without resampling.
Sample Arrival Time
Samples should arrive at the laboratory before 3:30 pm to ensure that all requested tests can be completed that day. For samples that arrive after 3:30 pm some tests may be done that day but some will not be completed until the following day.
Emergency or “STAT” Requests
All requests for “STAT” service should be addressed to the laboratory. Consideration should be given to which individual tests are required “STAT” and which tests can be done at the standard work schedule.
Multiple Sample Submission
Requests involving more than 20 samples per case or per farm require a 24 hour notice.
The laboratory will be able to do profiles on herds. In view of the expense involved, it is important that one carefully selects the profiles and specific tests required.
Projects involving many repeated samples or large batches of samples should be discussed with the laboratory prior to sampling.
Samples in lavender-topped (EDTA) tubes for CBC (complete blood count) should be forwarded to the laboratory as soon as possible. Samples that are two days old or more when received by the Diagnostic Services laboratories could be inaccurate. Always include air-dried, unfixed, non- refrigerated smears made at the time of sampling. Meaningful smears cannot be made from shipped EDTA blood. The routine hematology tests that can be performed on shipped blood samples are listed with appropriate information and comments.
TEST SAMPLE REQUIREMENTS COMMENTS
WBC White Blood Cell count Whole blood (EDTA) Gently invert and rotate
RBC Red Blood Cell count
MCV Mean Cell Volume MCH Mean Cell Hemoglobin MCHC Mean Cell Hemoglobin Concentration.
RDW Red Blood Cell Distribution Width
MPV Mean Platelet Volume
PDW Platelet Distribution Width Retic Reticulocyte (when applicable) HB Heinz Body
TP Plasma Total Protein
Fib Fibrinogen (large animals only) (lavender vial)
Small and Large Animal patients require 3 ml of whole blood to complete all of the tests listed. vial immediately after collection.
Vial must be free of clots.
Vials should be more than half full – preferably completely full.
WBC Differential 2 freshly made AIR DRIED Avoid submitting blood
Preparation of blood smears:
smears. Please see the following comments.
smears in the same package with tissues in formalin – the fumes can cause alterations in the staining.
- Smears can be made directly from the venipuncture or from a well-mixed EDTA sample immediately after collection.
- Smear preparation technique aids:
- Use clean glass slides with a bevel edge.
- Do not use too large a drop of blood.
- Smears should be made on a firm surface.
- Air dry rapidly by waving – DO NOT blow on smear OR expose to moisture. Do not refrigerate or stain.