The purpose of the present paper has been evaluating the biochemical changes in rabbits experimentally infected by Trypanosome evansi. Six male rabbits, separated in two groups, were used with the group A, the control group, being composed by non-infected animals and the group B composed by rodents infected with a T. evansi stump. The animals were maintained at room temperature and they have been analyzed during 120 days through 5 blood collections on days 1, 20, 40, 60 and 120. The biochemical changes observed in the infected rabbits were hyperproteinemia, hyperglobulinemia, increase on the urea levels, and significant decrease on ALT and albumin. The creatinine remained within the normality parameters. The rodents belonging to the group B have shown biochemical changes even after 80 days when the protozoon was not observed in the circulation anymore.