Effect of venipuncture site and anticoagulant on selected hematologic values in black rhinoceros (Diceros bicornis).

Paired blood samples were collected from the ear and radial vein of four captive healthy adult black rhinoceroses (Diceros bicornis). Samples were collected using heparin or ethylenediaminetetraacetic acid (EDTA) as an anticoagulant. Packed cell volume (PCV) and total protein (TP) values were compared between samples drawn from the two venipuncture sites and treated with the two anticoagulants to determine whether statistically significant variation occurred. No significant difference in the grouped values was observed when venipuncture sites (ear and radial vein) were compared using the same anticoagulant (heparin). However, when comparing different anticoagulants (EDTA and heparin) used to collect blood from the radial vein, the grouped-heparinized samples had higher mean PCV and TP values than did the EDTA-treated samples. These differences may be important when performing serial sampling in a sick rhinoceros and suggest that the choice of anticoagulant should be consistent, although selection of venipuncture site may be less important when monitoring selected hematologic values in black rhinoceroses.