Narated By Al-Bara’ ibn Azib : Ubayd ibn Firuz said: I asked al-Bara’ ibn Azib: What should be avoided in sacrificial animals? He said: The Apostle of Allah (PBUH) stood among us, and my fingers are smaller than his fingers, and my fingertips are smaller than his fingertips. He said (pointing with his fingers): Four (types of animals) should be avoided in sacrifice: A One-eyed animal which has obviously lost the sight of one eye, a sick animal which is obviously sick, a lame animal which obviously limps and an animal with a broken leg with no marrow. I also detest an animal which has defective teeth. He said: Leave what you detest, but do not make it illegal for anyone.
Abu Dawud said: (By a lean animal is meant) an animal which has no marrow.