Gov. Christie vetoed a measure Friday to ban crates used to confine pregnant pigs, slamming it as a "solution in search of a problem" and a "political movement masquerading as substantive policy."

"We do not have an issue with gestation crates in New Jersey," Christie wrote in his veto message. He urged the Legislature to work on "significant issues" and "stop following misguided partisans and special interest groups who want to use the lawmaking process as a political cudgel on issues outside our borders."

The move is unlikely to affect New Jersey farmers or their pigs - it's unclear whether any of the state's pig farmers use the crates.

But it prompted a rebuke from some legislators and the Humane Society of the United States, which had campaigned in favor of the bill.

The society accused Christie of bowing to the "Iowa pork industry," a reference to that state's status as host of the first presidential caucus.

Christie, who as chair of the Republican Governors Association visited Iowa several times this year to campaign for Gov. Terry Branstad, is considering a run for the White House in 2016.

He reportedly told an Iowa pork producer during a visit that he intended to veto the bill.

"Obviously, the governor is putting his personal political ambitions ahead of the humane treatment of animals," State Sen. Raymond J. Lesniak (D., Union), who sponsored the bill, said in a statement.

Lesniak added on Twitter: "Shame! Shame! Shame! Christie vetoes gestation crate ban. To the mattresses!"

The National Pork Producers Council says the metal crates let farmers better care for sows by preventing them from fighting or eating and defecating in the same place.

Animal-rights groups say the crates are cruel because pigs can't turn around in them. Nine states and several countries are moving away from gestation crates, the group says, and large pork buyers such as McDonald's have removed farms that use them from their supply chain.

Christie's veto was anticipated, given that he had rejected a similar bill last year. But supporters reintroduced the legislation, and celebrities such as Danny DeVito supported the society's push by asking the governor to sign it.

Most recently, The Daily Show With Jon Stewart produced a segment on the issue, and Stewart questioned whether Christie had been influenced by "the citizens of Iowa who elected you governor of New Jersey."

In his veto message, Christie said the state Board of Agriculture and Department of Agriculture had adopted "humane standards" that "have put New Jersey at the vanguard of protecting domestic livestock from animal cruelty."