What physical defects disqualify a sacrificial animal?

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There is no known scholarly dispute regarding the disqualification of four major defects: the overtly one-eyed animal (*a'wra' bain 'awraha*), the overtly sick animal (*maridah bain mardaha*), the overtly lame animal (*'arja' bain zal'iha*), and the extremely emaciated animal that lacks marrow (*'ajfa' allati la tunqi*). This is based on the Hadith of Al-Bara' where the Prophet (peace be upon him) listed these four defects as invalid for sacrifice. The overtly one-eyed animal is one whose eye has completely disappeared. The overtly sick animal is one whose illness visibly affects it, as this reduces its flesh. The overtly lame animal is one whose gait prevents it from keeping up with the herd to graze, thus reducing its flesh. The emaciated animal (*'ajfa'*) is one whose bones lack marrow (*naqiyy*) due to extreme leanness, leaving it mostly bone.