The aim of this study was to evaluate the effect of a short-acting antipsychotic (acepromazine) on the stress response to transport in roe deer ( C. capreolus ). 21 roe deer in France were submitted to a 9-h road journey in order to reintroduce and restock this species into Catalonia (northeastern Spain) in January 1999 and March 2001. The animals were divided into two groups: animals in the treatment group received an intramuscular injection of acepromazine (0.13 mg/kg in 0.5 ml; n=9) while animals in the control group received the same volume of saline (n=12). Clinical (heart rate and body temperature, measured during transport using remote devices), haematological and biochemical indicators of stress were used to evaluate the effect of the antipsychotic. Heart rate increased during transportation but no differences were found between groups. Body temperature decreased during transportation in both groups but this reduction was faster in acepromazine-treated animals. Comparison of blood parameters before and after transport revealed significantly lower red blood cell counts and haemoglobin concentrations after transport in treated animals compared with control animals; a reduction in lymphocyte count, eosinophil count and serum creatinine levels over transport in treated animals; a decrease in serum potassium levels over transport in the control group; an increase in serum creatine kinase (CK), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities over transport in control animals; an increase in serum urea and chloride concentrations over transport in both groups and finally a decrease in serum glucose concentrations in both groups. These results demonstrate the suitability of acepromazine in transport operations in order to reduce the stress response and prevent its adverse effects in roe deer.