They say a ban would cost US taxpayers millions and would make conditions worse for an estimated 100,000 unwanted horses every year.
"Unwanted horses are an unfortunate reality," wrote the leaders of the House Committee on Agriculture and the House Committee on Energy and Commerce, Collin Peterson, John Dingell, Bob Goodlatte and Joe Barton.
The proposed ban is back before the 110th Congress, having failed to complete its passage through the US legislative process before fresh elections late last year for a new Congress and Senate. The proposed law was passed by the 109th Congress, but had not got a hearing before the Senate.
This legislation, which is being promoted by PETA and the Humane Society of the United States, is bad for horse welfare, bad for animal agriculture, and bad for the U.S. economy," the Congress members said in their open letter.
"Every year in this country there are tens of thousands of unwanted horses abandoned, just as there are millions of healthy, but abandoned cats and dogs. As is the case with abandoned cats and dogs, the nation's infrastructure of animal rescue facilities for horses is already overrun.
"No-one has any idea how 90,000 or more unwanted horses that currently go to the processing plants will be cared for if the plants are closed. That's 90,000 additional unwanted horses every year. What we do know is that it will cost millions of dollars that are not budgeted in the legislation.
"Millions of cats and dogs are humanely euthanized each year. But disposal of unwanted horses is not as simple as disposal of unwanted cats and dogs. It's illegal in many states to bury horses because they are vectors for West Nile virus.
"Horse owners who can no longer care for their horses face a difficult choice. They can hire a veterinarian to euthanize the animal and dispose of it at a cost of several hundred dollars. They can try to find adoptive homes. They can sell the horses at auction. Or they can sell the horses directly to one of the processing plants. The choice is up to the owners, and we believe all of these options should be available to them."
They argued that federal law required the horses to be treated humanely and that inspectors could shut the plants for violations.
"Over 200 national, state, and local horse owner organizations, humane groups, and state and county government associations oppose the American Horse Slaughter Prevention Act because they know that the processing plants serve a vital function in assuring a humane, federally supervised end-of-life option for unwanted horses."
They point to a study suggesting the ban could cost over $US500 million within five years.
Collin Peterson is chairman of the Committee on Agriculture; John. Dingell is chairman of the committee on Energy and Commerce; Bob Goodlatte is the ranking minority member on the Committee of Agriculture, and Joe Barton the ranking minority member on the Energy and Commerce Committee.
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