Turkey's Yildiz receives several bids for Ak Gida stake - sources

* Sources say IPO for Ak Gida remains an option * Application for up to 45 percent IPO made in March * Yildiz bought United Biscuits in November By Asli Kandemir ISTANBUL, April 10 (Reuters) - Yildiz Holding, Turkey's largest food group, has had several bids for a stake in its dairy business Ak Gida that could be worth some $950 million, but a stock market listing is still an option, sources familiar with the matter said. In January, Yildiz said it had mandated HSBC and Turkish investment bank U