Abstract
This article presents the results of a comprehensive study of clinical, hematological, and morphological changes observed in dogs affected by canine transmissible venereal tumor (CTVT). The study was conducted in 2024–2025 at a veterinary diagnostic center in Astana. The aim of the research was to assess the prevalence of CTVT among dogs, identify risk factors for disease development, and characterize the main diagnostic features of the tumor. A total of 2,500 dogs of various breeds, age groups, and housing conditions underwent clinical examination. Among the examined animals, oncological pathology was identified in 425 cases, of which 23 dogs (5.4%) were diagnosed with CTVT. Analysis of anamnestic data demonstrated that the incidence of CTVT depends on sex, age, breed, and housing conditions. The disease was predominantly recorded in male dogs, which accounted for 73.9% of cases, likely due to transmission mechanisms and behavioral factors. Clinical investigations revealed that the main clinical signs of the disease included bloody or purulent discharge from the external genital organs and the formation of tumor-like masses in the genital area. In complicated cases, signs of general intoxication were observed, including increased body temperature, general weakness, and decreased appetite. Hematological studies revealed the development of anemia and leukocytosis in severe forms of the disease. Cytological examination identified characteristic morphological features of tumor cells, fully confirming the diagnosis. The obtained results expand current knowledge of CTVT pathogenesis and may be used to improve early diagnostic approaches and enhance the effectiveness of veterinary oncological practice.