Animal rights campaigners are calling for a ban on the activity. Picture: @3dogsandanag, Instagram

London - Blue coats, rainbow manes and unicorn horns – these horses look like toys brought to life.

It’s all down to a party craze that sees children paint spots, stripes and hearts on horses. Some are even given the unicorn treatment, with horns and glitter.

Organisers say the paint is non-toxic and harmless to the animals, which simply feel like they are being groomed while the paint is brushed on.

But animal rights campaigners are calling for a ban on the activity – in which horses are made to look like My Little Pony toys.

#myhappyequine #therapysession #equine #love #glittertattoos

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Sophie Tomlinson, who started a petition to end the £150-per-hour (about R3 000) parties, said ponies should not be used as chalkboards.

"It’d be great to nip this one in the bud and urge respectful ways to entice children with animals and art, such as painting pictures of the ponies," she said.

Dr Mark Kennedy, equine specialist at the RSPCA, also had concerns. "We understand children love getting close to animals but we would urge any such encounters to focus on fostering compassion towards animals and providing education about how to act safely around horses and ponies and meet their complex needs," he said.

But Helen Preece, the owner of My Happy Equine, a company that sells the paints, said they could be easily washed off and the activity was no different to farmers painting numbers on their sheep.

She said campaigners should instead "put all their energy into actual cruelty and neglect cases, rather than pony painting". Others also defended the parties.