It's hoped a new code of welfare for horses and donkeys will result in the animals being better treated.

It's been years in the making but the Ministry for Primary Industries has just released a code of welfare for the animals.

There was already a code for chickens, llamas, cats and dogs but until now there's never been one for horses and donkeys.

It comes into force today and there are plans to regulate aspects of it.

National Animal Welfare Advisory Committee Chair John Hellstrom said the code covers everything from the racing industry to recreational horse owners.

"W expect it will bring a lot of issues to the attention of the public, that people will start thinking about these things in a way that they haven't before."

Mr Hellstrom said the code will draw attention to some long standing issues.

"Issues around branding, transport, housing, there's a whole raft of stuff in there, but the codes make quite clear what people can do to minimise the stress on their horses."