[Avodah] diff between small nick in koneh vs veshet

[Alan Rubin]

Chaim Manaster asked

> can you explain why a small nick in the veshet produces a traifa (which will not survive 12 months)
> whereas it won't in the koneh unless it is rov

It can difficult to relate rabbinic rules on what constitutes traifa
to our understanding of pathophysiology but let me venture the
following:

A nick in the trachea is only going to harm the animal if it allows
blood and fluid into the trachea which runs down into the lungs. If it
allows air into the trachea that is not a problem, it is a normal
function of the trachea to transmit air to the lungs and indeed in a
tracheotomy an incision is made in the trachea precisely for this
purpose. At any rate I would guess that even a large nick in the
trachea will not kill an animal unless there is significant damage to
blood vessels. I frequently take fine needle aspiration cytology
specimens from the thyroid gland. Very occasionally the needle can
enter the trachea. This does not cause any ill effects and the patient
usually does not notice.

The problem with even a small nick in the oesophagus is that it can
lead to life threatening infection in the surrounding tissue. Ruptured
oesophagus is a serious medical emergency.

Alan Rubin