Authorities in the US state of Pennsylvania have asked for the public's help, after a horse riddled with over 100 paintballs was found abandoned at a stable.

The Lancaster County SPCA said the 20-year-old Appaloosa-Arabian mix was discovered on Monday.

The horse, which is blind in one eye, had been struck by about 130 paintballs at close range, the SPCA said.

The group posted pictures of the horse on Facebook, which showed the animal covered in several colours of paint.

This image shows the damage done to the horse | Image: Facebook/Lancaster County SPCA

SPCA executive director Susan Martin said the horse was "in a substantial amount of pain when touched".

She added the horse faced a lengthy recovery but was expected to survive.

The horse was found in a stall at the New Holland Sales Stable after sales ended for the day.

It had not been registered for the sale and had no visible identification, the SPCA said.

Animal cruelty investigators are asking anyone with information on the horse's owner to come forward.