Abu Dawud Book 9, Hadith Number 2824.

Chapter : The atirah.

Narated By Nubayshah : A man called the Apostle of Allah (PBUH): 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 Abu Qilabah: How many pasturing animals? He replied: One hundred.