Bone Marrow
Specimens of bone marrow will yield the most information if both a core biopsy and aspirate slides are submitted. The biopsy should be cut first, and the core placed in a tissue processing cassette, labeled and dropped into a formalin container. The aspirate needle then can be placed into the same puncture site as the biopsy needle. After placing the needle, attach a large bore syringe (10-20 cc) rinsed with a little liquid EDTA to help control clotting. Pull quickly and forcefully to aspirate 0.5-1.0 mL of sample into the needle. More is not better here as the negative pressure will rapidly rupture capillaries in the marrow, causing influx of peripheral blood. Place a portion of the aspirate into a LTT, which prevents clotting and preserves cellular morphology. Make the remainder into fresh smears. If hemodilution occurred, dispense the aspirate onto a glass surface and pick out spicule material to make smears. Send aspirate specimens in separate bags from the core biopsy to avoid formalin contamination

Biopsy Tissue
Tissue specimens for histology must be preserved and transported in formalin (10 parts formalin to 1 part tissue). The ideal tissue specimen is less than an inch thick. OSHA and Transportation Safety Regulations limit the size and quantity of formalin containers that can be shipped. Use an Antech supplied or FAA approved container, place it in a ziplock plastic bag, and then in a second outer bag that contains the requisition. Also, do not enclose cytology samples in bags containing formalin-fixed tissues. Samples packaged inappropriately may not be picked up by the courier.

Very Large Specimen
Several (preferably 3 or more) representative sections of large tissues or organs should be selected, preserved and transported for histology. The remainder should be placed in a large plastic container of formalin, refrigerated, and retained at the clinic in case additional samples are needed.

Tissue Orientation and Information
Knowing the orientation and other facts about the tissue mass is critical to the pathologist. A diagram on the requisition form is helpful. Borders and areas of interest on the mass can be marked with colored or numbered sutures. Please state if the entire mass has been excised, if all is being submitted, or if it had to be divided into sections before submission.

Very Small Specimen
Tiny samples, such as from endoscopy, are best preserved if they are first placed in a labeled tissue cassette holder (available from Antech) and then dropped into formalin. Small biopsies should not be placed into a container with large tissue, as they are easily lost.

Cytology Fluid
Fluids for cytology should be submitted in both RTT and LTT. For very small samples, a LTT is preferred. Cellular morphology is preserved by making 2-4 fresh smears on glass slides and allowing them to air dry. Do not add fixative or stain to any cytology smears. Urine smears for cytology should be made from fresh unstained urine sediment.

Collection Site/Source, Animal History & Status
Information about the animal is extremely important to the microbiologist in processing a culture and seeking certain pathogens, and to the pathologist in viewing a histology or cytology specimen. If the specimen comes from a necropsy, this should be stated clearly on the requisition, along with the site of collection, type of specimen (wound, abscess, body fluid, tissue, etc.) and relevant clinical history. Please note reference numbers or dates of previous reports from Antech that will allow these materials to be reviewed.

Preparation of biopsy samples is a multi-step, labor-intensive process. Generally, Antech’s expected turn around time is 2–4 business days (Monday thru Friday) from the time the sample reaches the laboratory.

Some samples require special preparation and handling such as additional fixation time, decalcification, gross dissection by the pathologist, and/or special staining procedures. These procedures may delay receipt of your final report.