When you dog splits a toenail, it may look like a grievous injury -- but it is rarely an emergency. The split may have occurred naturally or may be the result of a traumatic injury. Treating the toenail depends on the depth and severity of the split.
A shallow split is one that has broken just through the surface of the toenail and does not breach the quick. Shallow splits typically do not bleed and are not typically painful to your dog. Wipe the area around the split with a warm, wet rag to remove debris, and carefully dry the toe. Shallow splits often heal on their own, so do not panic if the broken parts of the toenail fall off as the nail heals.
Deep splits are injuries that split the nail into the quick; these are often very painful. Your dog may be reluctant to let you look at the nail, so be patient and handle the foot gently to prevent unnecessary discomfort. Deep splits may also bleed; an application of a coagulant, such as cornstarch of styptic power, will stop the bleeding. Wash the area with mild soap and water and allow the nail to air dry.
When to See the Vet
Schedule your dog for a veterinary appointment to clip off the split nail. Clipping a split toenail can cause further damage if not done properly, and a vet will know exactly where to cut the nail. A little limping after a deep split is normal, but the dog's refusal to use the foot is cause for veterinary intervention. Incessant licking, chewing or biting of the injured toe should also be examined by a vet, as should a nail that continues to bleed even after an application of coagulant.