China Mengniu Dairy Co., the nation’s biggest dairy company, may bid for Pfizer Inc. (PFE)’s infant-nutrition business, two people with knowledge of the matter said. Mengniu’s consideration of a potential bid is at an early stage, the people said, asking not to be identified because the information is private. The company won’t decide whether to proceed until more financial data on the unit is available, one of the people said. Mengniu said in a stock-exchange filing today that it isn’t “in any direct negotiation” with Pfizer.