Poultry giant Tyson Foods Inc. won an...

Poultry giant Tyson Foods Inc. won an important round in its fight to acquire rival Holly Farms Corp. for $1.1 billion when a judge blocked the target company from merging with ConAgra Corp. The ruling evidently means Tyson can proceed with its unsolicited $54-a-share cash tender offer for the company. Holly, based in Memphis, Tenn., has been resisting Tyson’s overtures and sought a merger with Omaha-based ConAgra to thwart an unfriendly takeover. Under that deal, arranged in November, ConAgra would acquire Tyson in a stock swap valued by securities analysts at about $995 million.