**Preface to "Comparative Pathology and Immunohistochemistry of Veterinary Species"**

Comparative pathology plays a fundamental role in the One Health concept and has the ultimate goal of advancing our medical knowledge of both human and veterinary species. Immunohistochemistry is a routine diagnostic technique that is often essential to reach a final diagnosis. It is usually part of any anatomic pathology study in cancer, infectious, or developmental diseases. There has been an exponential increase in use of immunohistochemical techniques in the last few decades, reflecting the current position that immunohistochemistry holds in most pathological laboratories and research centres. This book represents a collection of papers that aim to highlight the importance of immunohistochemical findings and their role in improving the understanding of pathogenesis and diagnosis of disease in domestic and wild animals, with a special focus on comparative aspects with the human species. It is mainly directed at veterinary students and professionals, researchers, and technicians who want to improve their immunohistochemical skills and update their knowledge in pathology, microbiology, and infectious diseases in both domestic and wildlife species.

> **Alejandro Su´arez-Bonnet and Gustavo A. Ram´ırez** *Editors*
