Cytology Tests & Protocols

The cytology services are customized and arranged with a consulting clinical pathologist. Contact the lab to setup a consult time/date. Customized pricing may apply for high volume testing, batch testing, or panels of tests. Please contact the Clinical Pathology Lab for additional information regarding discount pricing.

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Cytology tests


  • Test description: Cytological evaluation of solid tissue specimens. Cell counts are not included.
  • Test code:  Varies; please contact the lab for ordering specifics.
  • Specimen type:  Varies; common specimens include aspirates or impression smears from organs or mass lesions, aspiration of cystic lesions, and some fluid types for which there may be insufficient fluid for fluid analysis or no established normal values.
  • Preferred volume:  Varies; a single smear may be acceptable, however multiple smears (2-4) may be preferable depending on the size of the lesion and the need for special stains.
  • Species:  Most species

Body Fluid Analysis

  • Test description: Testing usually includes red cell counts, white cell counts, total protein* and cytological analysis.  Some chemistry tests may be performed on body fluids; please contact the laboratory for additional information.
  • Test code:  Varies; please contact the lab for ordering specifics.
  • Specimen type:  EDTA: Includes joint/synovial fluid, peritoneal fluid, pleural fluid & pericardial fluid.  Cerebrospinal fluid analysis requires special methods and is listed separately, below.
  • Preferred volume:  2.0 ml
  • Species:  Most species

*Protein is measured using a refractometer. For CSF, order total protein (see chemistry test menu).  For joints, a mucin clot test will be provided in place of protein testing.

Body Fluid Count only

  • Test description: Testing includes red cell counts and white cell counts.
  • Test code:  402.7
  • Specimen type:  EDTA: Includes joints, CSF, peritoneal fluid, pleural fluid & pericardial fluid.
  • Preferred volume:  2.0 ml
  • Species:  Most species


  • Test description: Order Body Fluid Analysis for cytological examination to diagnose central nervous system degeneration, neoplasia or inflammation. Refer to chemistry test menu for total protein and glucose measurements. Deliver to lab within 4 hours of collection at refrigerated temperatures.
  • Test code:  Varies
  • Specimen type:  EDTA & Red Topped Tube
  • Preferred volume:  1.0 ml
  • Species:  Most species

Bone Marrow

  • Test description: Cytological and histological evaluation of specimen.
  • Test code:  402.1
  • Specimen type:  Blood smear, aspirate in EDTA, and core biopsy in formalin. A complete blood count within 24 hours of bone marrow sampling is strongly recommended for optimal marrow interpretation.  See hematology test menu for ordering.
  • Preferred volume:  0.5 ml (aspirate)
  • Species:  Most species

Cytology protocols

Collection protocol

Please note: Consultation with a pathologist regarding study design, species, and spectrum of disease states is essential prior to submitting cytology samples for evaluation. Please contact Kim Little or Tammy Ruska in the lab to initiate this process.


Submitted cytology samples are stained with Wright-Giemsa (Romanowsky stain) using an automated process and are evaluated via light microscopy by board-certified veterinary pathologists. 

Samples submitted for fluid analysis may have cell counts performed manually via hemocytometer (CSF) or via an automated analyzer (Advia 2120 Hematology Analyzer, version 2.00.00, multi-species; Siemens Healthcare Diagnostics Inc., Deerfield, IL). Protein levels for body fluid analysis are measured via handheld refractometry. Protein levels for CSF must be analyzed via automated methods (Beckman Coulter; AU480; Beckman Coulter, Brea, CA) due to low concentrations and therefore must be ordered separately under the chemistry test section.

Sample requirements

Cytology samples may be taken by fine needle biopsy/aspiration and gently smeared on to new, clean, plain glass slides. Impression preparations from biopsy samples or cutaneous lesions are also acceptable. Alternatively, small amounts of whole tissue may be submitted for the pathologist to prepare impression smears. Fluid samples may also be submitted for cytologic analysis, cell counts and protein levels. Common sources of fluid include peritoneal fluid and thoracic fluid. 

Option Description of item Required volume (Note: Dependent on source)
1 Cytology – includes cytologic evaluation of solid tissue specimens and cystic lesions/fluids for which cell counts are not required Variable- a single slide may be sufficient, however several slides (2-4) may be preferable depending on the cellularity of the preparations
2 Body Fluid Analysis * 2 mL in EDTA
3 Cerebrospinal Fluid (CSF) Analysis*- must be submitted to the laboratory within 4 hours of collection, at refrigerated temperatures 1 mL in EDTA or Red Top
4 Bone Marrow Current blood smear, aspirate (0.5mL in EDTA), and core biopsy in formalin

*For measurement of CSF protein levels, you must also order total protein (see chemistry test menu). For joints, a mucin clot test will be provided in place of protein testing.

Appropriate tubes

Fluid samples for cytologic analysis and/or cell counts should be submitted in EDTA tubes (purple top) and for the latter, MUST be clot-free. Non-blood-contaminated CSF may be submitted in either a plain red top tube, or EDTA sample.

Sample handling

Slides should be carefully packed to minimize risk of breakage and should be labeled (if possible) in pencil with a legible, simplified numbering system. Prepared slides and fluids should not be exposed to formalin fumes or packaged with biopsy samples preserved in formalin. Formalin exposure results in altered staining characteristics and cell morphology, which in turn prevents adequate sample evaluation. 


Cytologic descriptions, pathologist’s interpretation, and comments are available in Word format.

Common interferences

Common causes of non-diagnostic samples include low cellularity samples and excessive hemodilution. Please contact the laboratory to discuss methods for minimizing these interferences.