Musnad Ahmad 907:237

'Abd al-Rahman ibn Mahdi narrated to us, Za'idah narrated to us, from Simak, from Ja'far ibn Abi Thawr, from Jabir ibn Samurah, from the Prophet (peace and blessings of Allah be upon him): That a man came to him and said, "Should I perform ablution after eating the meat of sheep?" He said, "No." He said, "Should I pray in their resting places?" He said, "Yes, if you wish." He said, "Should I perform ablution after eating the meat of camels?" He said, "Yes." He said, "Should I pray in their resting places?" He said, "No."