Sperm cytology: Kernechtrot–picroindigocarmine stain and dog semen


  • Adam Stern, DVM DACVP University of Florida College of Veterinary Medicine




animal sexual abuse, semen, dog, Kernechtrot–picroindigocarmine stain, Christmas tree stain, KPIC, companion animals


Animal sexual abuse cases present as an unusual scenario for forensic investigators. In this study, the kernechtrot–picroindigocarmine (KPIC, aka Christmas tree stain) staining properties of semen from 8 domestic dogs was compared to two samples of human sperm. In the head of the dog sperm, the acrosomal region stained pale red and the postacrosomal region stained dark red. There was a colorless band with a mean length of 0.59 μm within the sperm head between the acrosomal and postacrosomal regions. The colorless band was not identified within the human control samples nor reported in the literature. This data supports the use of KPIC stain for the examination of dog semen and further characterizes a unique staining pattern found in dog sperm that is not present in human sperm.

Author Biography

Adam Stern, DVM DACVP, University of Florida College of Veterinary Medicine

Department of Comparative, Diagnostic, and Population Medicine, University of Florida College of Veterinary Medicine, PO Box 100123, Gainesville, FL 32610-0123, USA






Domestic Animal