Because of a clerical error, the wrong version of a bill to end horse slaughter was delivered to the U.S. Senate. The error was discovered the week of Sept. 10, and the House of Representatives requested the bill be returned so the correct version can be sent. Lawmakers expect that the issue will be resolved quickly, according to Brent Dolen, press secretary for Kentucky Rep. Ed Whitfield. Whitfield and New York Rep. John Sweeney were lead sponsors of the bill while it was in the House.The original version of the American Horse Slaughter Prevention Act was passed by the House Sept. 7. However, a House clerk apparently delivered an amended version of the bill that would have allowed existing slaughter plants to remain open.Last year more than 90,000 horses were slaughtered in the United States. If the bill becomes law, the three existing plants, which are in Fort Worth and Kaufman, Texas, and DeKalb, Ill., will be shut down.