The Shaykh (Al-Mufid), narrated from Abu Al-Qasim Ja'far ibn Muhammad, from Muhammad ibn Yahya and Ahmad ibn Idris, from Muhammad ibn Ahmad ibn Yahya, from Muhammad ibn Isa, from Faris. He said: A man wrote to Imam عليه السلام asking about chicken dung - if it is permissible to pray in it? Imam عليه السلام wrote in reply: "No."