Reference for Bekhorot 106:14

מוקדשין פשיטא לאו דידיה נינהו

and blemishes which disqualify consecrated animals are frequent, for even a cataract disqualifies, animals for sacrifice are not easy to obtain.<span class="x" onmousemove="('comment',' Even by purchase and for this reason we do not set aside an animal nowadays as tithe.');">¹¹</span>

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