Reference for Chullin 178:21

ולדות קדשים במעי אמן הן קדושים דאיסור גיד ואיסור מוקדשין בהדי הדדי קאתי

[into the thigh]! - Rather we must suppose that he is dealing with the young of consecrated animals.<span class="x" onmousemove="('comment',' E.g. the young of a peace-offering which is consecrated the moment it was formed, even while in its dam's womb. At this same moment the prohibition of the sciatic nerve attaches to it.');">¹²</span>

Jastrow

Jastrow