BEIJING—Most Chinese consumers go to JD.com to buy electronic gadgets and other items. Restaurant operator Zhang Zong uses China’s No. 2 e-commerce company to deliver 400 million pounds of carp heads.

By outsourcing delivery of the fish heads and other kitchen essentials to JD.com, Ms. Zhang said she no longer has to rely on 200 different suppliers for the 33-outlet restaurant chain she runs. She added that she was also saving on delivery expenses.

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