Sahih Muslim 1019
It is narrated on the authority of Abu Huraira (that the Messenger of Allah) said:
Of course the person who gives to the family a she-camel as a gift, which gives milk morning and evening equal to a large bowl, its reward (the reward of the gift) is great.
حَدَّثَنَا زُهَيْرُ بْنُ حَرْبٍ، حَدَّثَنَا سُفْيَانُ بْنُ عُيَيْنَةَ، عَنْ أَبِي الزِّنَادِ، عَنِ الأَعْرَجِ، عَنْ أَبِي هُرَيْرَةَ، يَبْلُغُ بِهِ ‏
"‏ أَلاَ رَجُلٌ يَمْنَحُ أَهْلَ بَيْتٍ نَاقَةً تَغْدُو بِعُسٍّ وَتَرُوحُ بِعُسٍّ إِنَّ أَجْرَهَا لَعَظِيمٌ ‏"‏ ‏.‏