HEMATOLOGICAL REFERENCE INTERVALS OF THE SOUTH-AMERICAN RATTLESNAKE (CROTALUS-DURISSUS-TERRIFICUS, LAURENTI, 1768) IN CAPTIVITY

Blood samples were taken from 180 healthy specimens of South American rattlesnake (Crotalus durissus terrificus) kept in captivity. The red blood cell count (RBC), haematocrit value, haemoglobin concentration, mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH) and mean corpuscular haemoglobin concentration (MCHC) obtained were within the normal values reported for other Crotalid, Viperid and Elapid spe cies. Total leucocyte (WBC) counts were within the range described in other ophidian species. No significant changes were observed as a func tion of sex and age. The period of the year (seasonal variation) was t he only factor which had a significant influence on the haematological parameters, RBC counts, haematocrit, haemoglobin concentration, MCV, MCH and MCHC were 17-30% higher during wintertime (p<0.01), whereas th e WBC and thrombocyte counts were 15-20% higher (p<0.01) during the su mmer.