Abu Dawud said: Jallalah means an animal which eats filth and impurities.
In-book : Book 27, Hadith 51
English translation : Book 26, Hadith 3710
27. Drinks (Kitab Al-Ashribah)
باب الْمَوَاضِعِ الَّتِي نَهَى النَّبِيُّ صلى الله عليه وسلم عَنِ الْبَوْلِ فِيهَا