Casey’s General Stores Inc. said today that merger talks have ended with 7-Eleven Inc. The convenience store giant had acted as a foil to the hostile takeover bid for Ankeny-based Casey’s by the Canadian company Alimentation Couche-Tard Inc., which dropped its stock offer in late September. Casey’s said in a news release that its board of directors rejected 7-Eleven’s most recent offer of $43 a share for the company because it undervalued the company. The company had previously offered $40 a share. Couche-Tard’s final offer was $38.50 a share. Separately, Casey’s said it would buy up to 44 Kabredlo’s convenience store locations to expand its presence in Nebraska and Kansas. It said it expected the deal to add to earnings in the first year of operation. All of the stores will operate under the Casey’s General Stores name. Casey’s stock was trading at $39.60 a share at 10:06 a.m. Iowa time after closing at $41.45 on Tuesday.