The diagnostic methodologies of clinical examination, radiographic evaluation, and laboratory data may not always confirm a diagnosis. In such cases, cytology proves to be a crucial tool in confirming disease processes or conditions. Presently, there is a need for less invasive and cost-effective methods for tumor diagnosis (Sangha et al., 2011). The success of cytological diagnosis relies on the collection of appropriate representative cells, specimen preparation, and processing, as well as the interpretation of smears, which are all interdependent procedures (Roszel, 1981; Lumsden and Baker, 2000).

The arrangement of neoplastic cells within tissue is critical for determining the diagnosis of various types of tumors, evaluating surgical margins, and distinguishing between benign and malignant tumors (Stirtzinger, 1988). The role of cytology as a diagnostic tool in veterinary medicine is continuously developing and expanding, establishing itself as a reliable, minimally invasive method for obtaining a tissue diagnosis over the last two decades.

As clinicians increase their use of diagnostic techniques and cytopathologists gain experience with a wider range of lesions, tissue samples, disease processes, and accuracy of the diagnosis must be improved (Meinkoth and Cowell, 2002). Cytology serves as a screening diagnostic tool, classifying lesions as inflammatory, hyperplastic, or neoplastic. An experienced cytologist can definitively diagnose specific neoplasms, provide tentative diagnoses for various types of tumors, identify sites of tumor metastasis, and monitor tumor regrowth following anticancer therapy. Information obtained from cytology may prove useful in establishing a diagnosis, determining a prognosis, and formulating a diagnostic or therapeutic plan.

C. Balachandran, Ph.D., Former Vice Chancellor, Tamil Nadu Veterinary and Animal Sciences University, Madhavaram milk colony, Chennai – 600 051. He was born on 28.07.1957 in Mannargudi town of Tiruvarur District, Tamil Nadu. He obtained B.V.Sc., M.V.Sc. and Ph.D. (Veterinary Pathology) degrees from Madras Veterinary College. He started his career at Namakkal in 1980 and promoted as Associate Professor in 1988 and Professor in 1996. He served  as  Vice-Chancellor of Tamil Nadu Veterinary and Animal Sciences University (TANUVAS) for three years from 09-04-2018.He also served as Registrar of TANUVAS and as the Dean, Madras Veterinary College. He has published about 400 scientific articles including 73 articles in International journals. He was instrumental in introducing cytological diagnosis of disease in animals. His areas of research interests are avian diseases, cancer biology and indigenous medicinal effects. He has published about 50 popular articles. He served as Editor, Kalnadai Kathir, a TANUVAS Tamil Popular Magazine. He has about 90 awards to his credit. Notable Awards: University gold medal for the best thesis in avian diseases, Fellow of FAO, IAVP, National Academy of Veterinary Sciences and Academy of Science for Animal Welfare, Tamil Nadu State Scientist Award

N. Pazhanivel, Professor, Department of Veterinary Pathology, Madras Veterinary College, Chennai – 600 007. Dr. N. Pazhanivel, M.V.Sc., Ph.D., M.A. (Public Administration), PGDEVP., Diplomate ICVP., FASAW, FIAVP, ICMR DHR IF, and Professor of Pathology, Madras Veterinary College, Chennai-600007. His area of research includes oncology, avian oncogenic viruses, avian pathology, cytopathology, histopathology and toxicopathology. He has published 287 research articles (International -62; National-231). He has published 63 popular articles. He has presented 301 research papers (International-91; National-202). He has received 47 awards. He has published 3 books and 40 book chapters. He has completed 6 projects and currently 2 projects are handling. He has completed Post-Doctoral Fellowship Research Training at Pennsylvania State University, USA in 2020. He visited to Liverpool University, United Kingdom for educational training program under ICAR- NAHEP /IDP –TANUVAS during January to February,2023. He is acting as the Editor, The Indian Veterinary Journal from 2022 onwards. He acted as the Secretary, Indian College of Veterinary Pathologists (ICVP) from 2020 and now acting as Registrar, Indian College of Veterinary Pathologists (ICVP) from 2023 onwards.

S.Vairamuthu, Professor and Head  Centralised Clinical Laboratory, Madras Veterinary  College,Chennai-600 007Tamilnadu Veterinary and animal Sciences University, Chennai - 600 007.Tamilnadu, India. He has 33 years  of professional experience  including 16 years of  experience in Clinical Laboratory of Madras Veterinary College. Teaching UG students for 25 Years, Post graduate for 20 years and guided   15 post graduate students and 3 PhD scholars.  Expertise in Interpretation of hematology and serum biochemistry results. Screening of cytological smears for neoplastic ,inflammatory conditions and blood smears for blood parasites and blood pictures.Diagnostic Cytology – screening of  FNAC smears / impression smears from cutaneous and internal masses for diagnosis of tumours. Visted  University of  Maryland, Maryland USA short term training (3 months) in animal diseases diagnosis (molecular aspects) in Virginia Maryland regional College of Veterinary Medicine. Visited University of Bari, Italy training program on Educational Technology on Veterinary Medicine at College of  Veterinary Medicine ICAR- NAHEP /IDP -TANUVAS. Visited South Africa and Nairobi-Kenya -BBSRC, UK-TANUVAS collaborative Project.  Published more than 120 research papers including 35 in foreign journals. He has been received more than 20 awards including seven in national level.   

1 Introduction, 2 Techniques of Cytology, 3. Fixation, 4. Cytological Stains, 5. Ideal Smears, 6. Inflammatory Conditions, 7. Neoplastic Conditions