The measure sparked a lengthy debate Monday in the House, which voted 36-28 against the measure to have a study by the state Department of Agriculture.
A Roswell meat company has proposed resuming horse slaughtering and sued the federal government last year over inaction on its application.
Supporters said a slaughter plant would provide a humane way for dealing with unwanted horses and those left to starve by owners who can't afford to feed them. They said the horses could be processed to provide meat for human consumption in overseas markets.
Opponents said a better approach is to support private programs that care for unwanted or mistreated horses.