Abu Hasin (may Allah have mercy on him) said that Ibn al-Zubayr (may Allah be pleased with him) looked over his sacrificial animals, and among them was a one-eyed she-camel. He said: If the defect arose after it was bought, then sacrifice it; if the defect was there before it was bought, then replace it.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الحج / 10247