´Narrated Hujayyah bin 'Adi:` "Ali said: 'A cow is for seven.' I said: "And if it gives birth?' He said: 'Then slaughter its offspring with it.' I said: 'What if it is lame?' He said: 'When it has reached the place of ritual.' I said: 'What if it has a broken horn?' He said: 'There is no harm, we were ordered' - or - 'The Messenger of Allah (ﷺ) ordered us, to check the two eyes and the two ears.'"
Hadith Referenceسنن ترمذي / كتاب الأضاحى عن رسول الله صلى الله عليه وسلم / 1503
´Narrated 'Ali:` "The Messenger of Allah (ﷺ) prohibited that an animal with a A'dab (stump) horn or ear should be slaughtered as a sacrifice." Qatadah (one of the narrators) said: "So I mentioned this to Sa'eed bin Al-Musayyab and he said: 'The A'dab is that which equals or more than that.'"
Hadith Referenceسنن ترمذي / كتاب الأضاحى عن رسول الله صلى الله عليه وسلم / 1504