There is no fara and no atirah

It is narrated from Sayyiduna Nubayshah (may Allah be pleased with him) that a man asked the Prophet (peace and blessings be upon him) and said: "O Messenger of Allah (peace and blessings be upon him), in the Jahiliyyah we used to offer the 'atirah (a particular sacrifice) in the month of Rajab. What do you now command us?" The Messenger of Allah (peace and blessings be upon him) said: "Slaughter (a sacrifice) for Allah in any month, do good for the sake of Allah, and feed (people)."
This hadith has a sahih (authentic) chain, and they (the two Shaykhs) did not record it.

It is narrated from Sayyidah Aishah (may Allah be pleased with her) that the Prophet (peace and blessings be upon him) gave an order regarding the fara' (sacrificing the first offspring of a she-camel): that one out of every five (camels) should be sacrificed.
This hadith has a sahih (authentic) chain, and they (the two Shaykhs) did not record it.

It is narrated from Sayyiduna Abdullah bin Amr (may Allah be pleased with them both) that the Messenger of Allah (peace and blessings be upon him) was asked about the fara', and he (peace and blessings be upon him) said: "The fara' is a right, but to leave it until it becomes an ibn makhad (one year old) or an ibn labun (two years old), and it is used as a mount in the path of Allah, or it is given to a widow, is far better than that you slaughter it (while still young) with its flesh sticking to its hide (that is, while it is very lean) and make your she-camel distraught (with grief at losing her young)."

Sayyiduna Abu Hurayrah (may Allah be pleased with him) said concerning the fara': It is a right, but do not slaughter it while it is a gharah (that is, completely lean and weak) whose sticky substance clings to your hands; rather, let it drink (its mother's) milk until, when it becomes among the best of wealth, then slaughter it.
This hadith is sahih (authentic) with this chain, and the musnad hadith before it is also sahih according to the conditions I have set for this book.

It is narrated from Sayyiduna al-Harith bin Amr al-Sahmi (may Allah be pleased with him) that he said: I saw the Messenger of Allah (peace and blessings be upon him), and I said: "(O Messenger of Allah (peace and blessings be upon him),) pray for forgiveness for me." He (peace and blessings be upon him) said: "May Allah forgive you." I said the same thing once or twice. Then a man asked: "O Messenger of Allah (peace and blessings be upon him), what do you say about the 'ata'ir and the fara'i'?" The Messenger of Allah (peace and blessings be upon him) said: "Whoever wishes may offer the 'atirah and whoever wishes may not, and whoever wishes may sacrifice the fara' and whoever wishes may not; and the sacrifice of a sheep (alone) is sufficient."
This hadith has a sahih (authentic) chain, because al-Harith bin Amr al-Sahmi is a well-known Companion and his descendants in Basrah are well known, while the two Shaykhs have agreed that the Messenger of Allah (peace and blessings be upon him) said: "There is no fara' and no 'atirah (that is, they no longer have the status in Islam that they had in the Jahiliyyah)."