Trimming the nails for one who intends to slaughter for Qurbani

 عَنْ أُمِّ سَلَمَةَ رضي الله عنها أَنَّ النَّبِيَّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَالَ إِذَا رَأَيْتُمْ هِلَالَ ذِي الْحِجَّةِ وَأَرَادَ أَحَدُكُمْ أَنْ يُضَحِّيَ فَلْيُمْسِكْ عَنْ شَعْرِهِ وَأَظْفَارِهِ

Ummu Salmah رضي الله عنها narrates that Nabi صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ said:

"When you see the crescent of Zul Hijjah and any one of you intend to perform Udhiyyah (slaughter an animal) then he should abstain from (cutting) his hair and nails."

Narrated by Muslim