Viewers in New Zealand have complained about a three-second clip in an advert showing horses mating.

The advert is promoting Cadbury’s Moro chocolate bars — a bar filled with whipped nougat and caramel centre and covered in chocolate, similar to a Mars bar.

Plugged as “New Zealand’s fourth favourite chocolate bar, allegedly” the advert promotes being the “fourth best” and that they are the real winners.

It features the fourth best disco dancer who dances to his own beat — saying the first, second and third best are “boring”

A yatching crew who came fourth in the Americas Cup and a team of sycronised swimmers, who came fourth in a competition are also in the ad.

But some viewers were upset when the advert focused on Thunderfoot, a horse that came fourth in the Melbourne Cup.

He is seen covering a mare with the narrative “he won’t race again, he has better things to do.”

Watch the video

One viewer said it was “offensive to watch an advert in which two horses were fornicating. I am the parent of an eight-year-old and a two-year-old and work hard at preserving their innocence”.

But the complaints have been rejected by the country’s Advertising Standards Authority (ASA)

Legal counsel for Cadbury’s and advert makers DDB said the commercial was aimed at young males, between 15-25 years old.

It had a rating of PGR — enabling it to be broadcast after 7pm and between appropriate weekday daytime adult shows.

The Television Commercials Approval Bureau had expected some people to react, but decided it was unlikely for it to “cause serious or widespread offence”.

“The humour is admittedly rather juvenile and of dubious taste but the footage is not gratuitous and does not depict anything not seen daily on farms up and down the country.”

“To take offence seems rather prudish and curiously anthropomorphic (it is not technically possible for animals to ‘fornicate’),” the bureau said.