Delta Downs in Vinton, La., and Sam Houston Race Park in Houston have canceled their races for Saturday night because of freezing temperatures. It is the second straight program both tracks have had to scrap because of a cold front that has settled into the region in the last week.\n"With tonight's temperatures forecasted to drop below freezing by post time, combined with the already frozen condition of our track surface, we are forced to cancel tonight's live racing program for the safety of the horses and jockeys," said Andrea Young, the president and chief operating officer of Sam Houston. \nSam Houston has also canceled training for Sunday. \nDelta on Friday night canceled the final eight races of its program because of the weather. The cold front also forced Louisiana Downs near Shreveport to call off the opening card of its Quarter Horse meet on Saturday. In addition, the freezing temperatures have disrupted training at Oaklawn Park in Hot Springs, Ark.