The National Cooperative Dairy Federation of India buy 20,000 tonne maize, 9,800 tonne de-oiled rice bran, and 2,550 tonne polished rice through a reverse electronic auction on Tuesday. The commodities, used as cattle feed, will be bought on behalf of the Karnataka Milk Federation. The federation, which has nearly 200 dairy cooperatives as members, has developed an online trading platform to purchase feed stock and sell dairy products.