Sahih Bukhari Volume 7, Book 69, Hadith Number 513.

Narrated By Abu Huraira : Allah’s Apostle said, “The best object of charity is a she-camel which has (newly) given birth and gives plenty of milk, or a she-goat which gives plenty of milk; and is given to somebody to utilize its milk by milking one bowl in the morning and one in the evening.”