The Prophet ﷺ said: There is no slaughtering (at the grave) in Islam. 'Abd al-Razzaq said: They used to slaughter cows or sheep at grave.  

قَالَ رَسُولُ اللَّهِ ﷺ لاَ عَقْرَ فِي الإِسْلاَمِ قَالَ عَبْدُ الرَّزَّاقِ كَانُوا يَعْقِرُونَ عِنْدَ الْقَبْرِ بَقَرَةً أَوْ شَاةً