Bird flu has not spread among chickens in Delhi, an official said on Thursday after all the 100 samples taken from Asia's largest poultry market in Ghazipur tested negative, following which Delhi Chief Minister Arvind Kejriwal ordered opening of the mandi while all the three municipal corporations in Delhi lifted the ban imposed on sale, storage of poultry or processed chicken meat. Welcoming the Delhi government and civic authorities decision, Union Animal Husbandry Minister Giriraj Singh said that Delhi government's decision to open Ghazipur poultry market will send a positive message throughout the country. Earlier, samples taken from crows and ducks at parks and lakes in the national capital tested positive for the avian influenza.