Chullin 44 - The Pharynx
The stiff, uppermost section of the food-pipe, roughly equivalent to the pharynx, is where the food-pipe is attached to the jaw. Rav says that any slight puncture in it renders the animal a terefah . Why? According to Rav, there is no limit where one can cut the food-pipe, and it is only the windpipe that has limits. It follows then that the pharynx is a place of shechitah, and no puncture there is tolerated. On the contrary, Shmuel says that there is a definite limit where the food-pipe can be cut, and it is below the pharynx. Accordingly, the pharynx itself can be punctured, as long as the defect is less than its half.
If the majority of the trachea of an animal was split, it is terefah. They brought such a case to examine before Rav, and Rav ruled the animal terefah, because he measured on the outside of the windpipe. However, Rabbah bar bar Chanah measured on the inside, declared the animal kosher, and bought thirteen measures of its meat. But didn't he buy it on the cheap and therefore benefited from his own ruling? - No, he didn't, because he bought it at the going market price.
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