Reference for Bekhorot 111:25

א"ק תעשה בשעת עשייה מיעט הכתוב

And if you will say that it is a [recognized] teaching, then it must be the opinion of R'Simeon B'Judah.<span class="x" onmousemove="('comment',' For according to his opinion an animal within seven days of its birth can be dedicated, and therefore the law of an animal bought applies to it. He admits nevertheless that if an embryo was in the inside of the mother, the law of an animal bought does not apply to it.');">¹³</span>

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