The American Legion, which is the biggest wartime veterans organization in the U.S., is urging the Senate to strip out language from a major spending bill that would ban most medical testing on dogs at the Department of Veterans Affairs.

The House easily approved the language as part of a package of four spending bills in July, and the amendment from Reps. Dave Brat, R-Va., and Dina Titus, D-Nev., was passed in a voice vote. The Senate was set to start work on those bills this week.

But opposition to the dog testing ban has surfaced since then, and late last week, The American Legion asked Senate Appropriations Committee Chairman Thad Cochran, R-Miss., to make sure the language is removed.

"[W]e find the VA's practices to be within recommended federal and ethical standards as established by the U.S. Department of Agriculture and the National Institutes of Health," the group wrote in its Sept. 1 letter to Cochran. "Based on this information, The American Legion opposes the amendment to the minibus ... and encourages VA to continue research vital to advancing the medical well-being of our nation's veterans."

The group said research at the VA has helped improve the lives of veterans with heart disease and diabetes, and has helped treat post traumatic stress disorder.

"Stopping VA research that can only be done with dogs will mean accepting that the care we offer our veterans must be limited to what we can do now in those areas," the group said.

"VA's efforts to develop some promising ways to restore the ability to cough to individuals with spinal cord injuries or other problems with respiratory control will stop, leaving people vulnerable to potentially lethal respiratory infections that could otherwise be avoided," the Legion wrote. "VA will not be able to pursue to some ways to reduce the damage that heart attacks cause to heart muscle."

"There are many pet owners and animal lovers in The American Legion," it added. "Sometimes animal research is needed for the greater good of protecting human life."

It's not clear whether the group's opposition will end up derailing the proposal. However, others have also come out against it.

Last month, Friends of VA Medical Care and Health Research called on lawmakers on the House Appropriations Committee to eliminate the language.

"Animal models play an essential role in advancing our understanding of human health and disease," that group wrote in a late August letter to the leaders of the House Appropriations Committee.

The group said is supports the ethical treatment of animals, but said the VA is already performing tests on dogs sparingly, and said the language in the bill goes too far.

"While we understand and appreciate the efforts to reduce use of dogs in animal research, we believe the policy included in the appropriations bill will impede scientific research and unnecessarily delay research advances for our nation's veterans," the group wrote.

In early August, Paralyzed Veterans of America also argued that the ban would lead to the "devaluation of the lives of catastrophically injured veterans."

Brat defended his proposal by saying his the language would still allow non-painful experiments to continue on dogs. But opponents of the language said it would block most of the experimentation that happens at the VA.