美国西南部野马数量过多导致资源紧张，威胁家畜养殖难等问题，新墨西哥州政府同意重新开启已关闭6年的野马屠宰场。

GWEN IFILL: There is renewed controversy in New Mexico over a plan to reopen horse slaughterhouses, which have been banned in this country for six years.

Hari Sreenivasan has our report about what's triggered this debate.

HARI SREENIVASAN: Several times a week this summer, residents of the Navajo Indian Reservation in New Mexico mapped out a game plan. They set up a temporary pen and then headed out by horseback and ATVs to round up groups of wild horses that have become a threat to the livelihood of farmers and ranchers here.

ERNY ZAH, Navajo Nation: These horses are bouncing between ranches, in between homesteads. They're, again, eating the forage, drinking the water. Each horse, feral horse, we estimate, eats anywhere between five and 18 pounds of forage a day. They drink five between five and 15 gallons of water a day.

HARI SREENIVASAN: Erny Zah, a spokesman for the tribe, estimates that feral horses — that is, horses that run wild but at one time were domesticated — cost the Navajos $200,000 a year in damages. There are approximately 70,000 of them in Northwestern New Mexico alone, and Zah says they are putting a tremendous strain on the land and resources, land that is already struggling from a catastrophic drought.

ERNY ZAH: You have cattle who are coming in under weight who are not as healthy. They're not getting as much money at these auctions for their cattle. So our ranchers that own cattle are losing out.

HARI SREENIVASAN: To try to ease the problem, tribal leaders have authorized these roundups, in which horses are chased across open land into makeshift corrals, and then loaded into trailers to head to auction.

Many of the horses end up in slaughterhouses in Canada and Mexico, their meat exported to China or Europe, where, unlike the U.S., horse meat is regularly consumed. The United States shut down horse slaughterhouses in this country six years ago, when it prohibited federal funding for inspectors.

But, recently, Congress removed that prohibition, and this summer, the USDA awarded the first permit that would allow horse slaughter to resume in the U.S. It was a decision that ignited a nationwide debate about the practice of killing horses for meat.

The permit was granted to Rick de los Santos, who, for more than 20 years, slaughtered cattle at his Valley Meat Company in Roswell, N.M. But his business had declined with the economic downturn. So he wanted to tap into a new market, knowing that more than 150,000 horses are shipped out annually for slaughter in Mexico and Canada.

RICK DE LOS SANTOS, slaughterhouse Oowner: The real problem here is the overabundance of horses that are going to slaughter anyway. We thought we would provide a service and do it humanely here in this country and be able to provide jobs for people that need jobs.

HARI SREENIVASAN: De los Santos was set to begin operations in August, but the U.S. Humane Society, which has long been an opponent of horse slaughter, filed a lawsuit, and a judge issued a temporary restraining order.

Phil Carter is with Animal Protection New Mexico. He says animal rights groups like his are pushing for a permanent ban, saying any kind of horse slaughter is cruel.

PHIL CARTER, Animal Protection New Mexico: You cannot slaughter horses humanely, no matter where you do it. Horses just do not adapt well to industrialized-scale slaughter.

They panic easily. They are very large, very large skulls on them, so it's extremely hard in an industrial capacity to kill them cleanly. And so we have to be able to provide more humane solutions than just regressing to this slaughter that 80 percent of Americans do not support.

RICK DE LOS SANTOS: Here, we would have one employee on the outside the plant here of this wall would open that shoot, and in would come in the livestock.

HARI SREENIVASAN: De los Santos disagrees. He gave the NewsHour a tour of the shut-down facility, which he says uses the most humane techniques available.

RICK DE LOS SANTOS: As the livestock come into the knocking chute, they can't see out. There's no noise going on. So they don't get spooked while they're in the knocking chute.

HARI SREENIVASAN: And he blames animal rights groups for distorting the facts about slaughter.

RICK DE LOS SANTOS: A lot of people that call in, if I sit there and talk to them and explain to them and educate them, then they calm down and they say, well, I didn't know that. I didn't know that.

WOMAN: They love people.

HARI SREENIVASAN: Even animal rights groups acknowledge that something must be done about the overpopulation of wild horses in the American Southwest. But they argue for the creation of more horse sanctuaries, like this one called The Horse Shelter just south of Santa Fe. The shelter accepts horses that have been mistreated or abandoned by owners and some that are rescued from the wild.

Here, the horses are fed and trained and most end up being adopted.

Still, shelter owner Jennifer Rios says organizations like hers will never be able to solve the problem alone.

JENNIFER RIOS, The Horse Shelter: The 75 horses we're able to help out at the time is really the tip of the iceberg. It is a Band-Aid to a much bigger problem. We do what we can. And for these horses, it makes all the difference. But for the overall problem, much more needs to be done.

Without funding, real funding and organized programs being put towards humane euthanasia and population control, this is all we will ever be able to do, and the problem is going to continue to spiral out of control.

HARI SREENIVASAN: Rios concedes that humane euthanasia and population control are very expensive remedies. Euthanasia costs roughly $300 per horse, and that's not including the cost to round it up. Right now, contraception for wild horses is difficult to administer.

It involves shooting darts from helicopters with a treatment that must be re-injected every two years. Rios is opposed to slaughter, but she says its not a simple issue. She says horses are dying every day in trucks as they're shipped out of the country and on the rangeland when they run out of food. She thinks the government has been delinquent by not spending enough money to deal with the problem.

JENNIFER RIOS: It's inhumane to let animals starve to death, dehydrate to death, procreate at a level that the environment is unable to support. So that's why, at the shelter, we wouldn't just say we were against slaughter. We are for humane alternatives.

HARI SREENIVASAN: The issue has also divided Native Americans.

Just this month, the Navajo Nation switched its position from supporting slaughterhouses to opposing them. It also ordered a halt to horse roundups on its land.

ERNY ZAH: For the Navajo people, this is a hard decision for us personally for each one of us individually, as leaders, as collective — as a collective clan, as a collective family, as a people. Rounding up horses is not something any of us want to do. These horses are sacred to us. We love our horses. But we love our land too.

HARI SREENIVASAN: For all the debate that has raged over this issue as of late, it's unlikely that Congress will allocate money for inspectors in the upcoming budget. And, so for another year at least, horse slaughterhouses in this country will remain closed.