EN
The studies were aimed at immunohistochemical determination of telomerase expression in cells of primary adenocarcinomas in mammary glands of bitches. Moreover, it was aimed at comparing the obtained results with an extent of Ki-67 antigen expression, which reflects the proliferation rate of tumour cells. Material for the studies was sampled during surgery in 35 bitches of various breed, ranging in age from 5 to 14 years, which developed mammary tumour. Using histopathology, the tumours were verified as representing adenocarcinomas. This was followed by immunohistochemical reactions for the detection of telomerase and Ki-67 expression. The obtained preparations were photographed and the images were subjected to computer-assisted analysis using the MultiScaneBase V 14.02 software. The obtained mean positive correlation (r = 0.26) between the expression of Ki-67 proliferative antigen and that of telomerase in mammary adenocarcinoma of bitches points at the involvement of the enzyme in neoplastic processes in animals, in an analogy to breast cancers in women.