EN
Measures of horn growth of Bulgarian chamois Rupicapra rupicapra balcanica Bolkay, 1925 were compared between males and females. The hypothesis that rapid early growth of horn is followed by slower subsequent growth was tested through the regression of the horn increment in the first two years against the third, fourth and fifth year respectively in the same individual. Sexual dimorphism in annual growth increment was significant up to the third year, males having higher values than females. Negative correlation coefficients were found when regressing the third, fourth and fifth individual annual increment on the second one in males, thus showing that individuals which had horns which grew fastest in the first two years tended to have slower horn growth in subsequent years.