Photo of dog in Jaisalmer with ear-notch visible on leading edge of left ear. - All dogs subject to sterilisation and/or vaccination as part ABC projects are ear-notched using a clamp and cauterizer whilst under anaesthetic. An ear-notch provides a permanent and visible mark that the dog is already sterilised and hence avoids them being caught unnecessarily. This photo shows a dog in Jaisalmer with an ear-notch on the leading edge of the left ear.
Hiby et al. BMC Veterinary Research 2011 7:46 doi:10.1186/1746-6148-7-46