The influence and the role of corticotrophin analogue 4-10 on the rabbits' behaviour in spontaneous conditions was analysed. The data analysis indicated that analogue 4-10 with modified aminoacid sequence in 8, 9, 10 positions significantly influenced the behavioural changes in the general model of behaviour. The 4-10 corticotrophin derivative caused the suppression of aggression, considerably reduced the tension and orientation-cognition reactions, however, it prolonged comfort and grooming significantly. This may prove the noticeable reaction of analogue 4-10 in modification of behavioural pattern, which was expressed by restraining the reaction of stressogenic character with simultaneous attenuation and prolongation of appetite reactions.