Nicky Wagner provides bodyguard duties for Bill English on election trail

National leader Bill English might want to put his MP Nicky Wagner on duty as a bodyguard after she hauled an animal welfare protester away from him during a speech in Christchurch.

English was speaking to supporters and members of the public at a shopping centre on Colombo St when a man carrying a sign with images of battery chickens sidled through the throngs of National supporters and got right in beside him.

English's police protection squad were too far away to intervene - but Wagner was not.

Without hesitation she grabbed the man and dragged him to the side where a protection squad officer took over.

As National's supporters booed, English reacted calmly, carrying on speaking and then addressed the concerns the protesters were raising.

"Animal welfare is something we've really focused on, because we have to turn the idea of animal welfare into practical steps and we have done that.

"We have taken the steps to change the production systems, change farming practices so that bobby calves are treated in a way that respects the animal welfare, so we've got changes in the pork industry so people find the production process there more acceptable."

The handful of protesters remained with their signs featuring a sow in a crate and battery chickens throughout English's speech but did not interject or heckle.

They jostled with National supporters who were trying to block the placards with their own National Party hoardings.

English had spoken with one of the protesters just before the incident soon after he arrived at the centre.

The woman had told him her concerns about sow crates and bobby calves and English had told her the Government had been reviewing the welfare codes and introducing new minimum standards.

However, the woman remained unconvinced.