A man called the Messenger of Allah ﷺ: We used to sacrifice Atirah in pre-Islamic days during Rajab; so what do you command us? He said: Sacrifice for the sake of Allah in any month whatever; obey Allah, Most High, and feed(the people). He said: We used to sacrifice a Fara' in pre-Islamic days, so what do you command us? He said: On every pasturing animal there is a Fara' which is fed by your cattle till it becomes strong and capable of carrying load. The narrator Nasr said (in his version): When it becomes capable of carrying load of the pilgrims, you may slaughter it and give its meat as charity (sadaqah). The narrator Khalid's version says: You (may give it) to the travellers, for it is better. Khalid said: I asked AbuQilabah: How many pasturing animals? He replied: One hundred.  

نُبَيْشَةُ نَادَى رَجُلٌ رَسُولَ اللَّهِ ﷺ إِنَّا كُنَّا نَعْتِرُ عَتِيرَةً فِي الْجَاهِلِيَّةِ فِي رَجَبٍ فَمَا تَأْمُرُنَا قَالَ اذْبَحُوا لِلَّهِ فِي أَىِّ شَهْرٍ كَانَ وَبَرُّوا اللَّهَ ﷻ وَأَطْعِمُوا قَالَ إِنَّا كُنَّا نُفْرِعُ فَرَعًا فِي الْجَاهِلِيَّةِ فَمَا تَأْمُرُنَا قَالَ فِي كُلِّ سَائِمَةٍ فَرَعٌ تَغْذُوهُ مَاشِيَتُكَ حَتَّى إِذَا اسْتَحْمَلَ قَالَ نَصْرٌ اسْتَحْمَلَ لِلْحَجِيجِ ذَبَحْتَهُ فَتَصَدَّقْتَ بِلَحْمِهِ قَالَ خَالِدٌ أَحْسَبُهُ قَالَ عَلَى ابْنِ السَّبِيلِ فَإِنَّ ذَلِكَ خَيْرٌ قَالَ خَالِدٌ قُلْتُ لأَبِي قِلاَبَةَ كَمِ السَّائِمَةُ قَالَ مِائَةٌ  

Prophet ﷺ sa saying: There is no fara' and 'atirah.  

أَنَّ النَّبِيَّ ﷺ قَالَ لاَ فَرَعَ وَلاَ عَتِيرَةَ  

Fara' was the first animal born to them (the Arabs) which they sacrificed.  

الْفَرَعُ أَوَّلُ النِّتَاجِ كَانَ يُنْتَجُ لَهُمْ فَيَذْبَحُونَهُ  

The Messenger of Allah ﷺ used to sacrifice goat out of every fifty goats. Abu Dawud said: Fara' means the first baby camel born (to the Arabs). They used to sacrifice it for their idols, and then eat it, and its skin was thrown on a tree. 'Atira was a sacrifice made during the first ten days of Rajab.  

أَمَرَنَا رَسُولُ اللَّهِ ﷺ مِنْ كُلِّ خَمْسِينَ شَاةً شَاةٌ