The results demonstrate clearly, for the first time, that the act of slaughter by ventral-neck incision is associated with noxious stimulation that would be expected to be painful in the period between the incision and subsequent loss of consciousness.
So anyway, here’s the science on pain at slaughter
https://www.cambridge.org/core/journals/animal-welfare/article/pain-perception-at-slaughter/463284EC5DCD5A60CE674AC004B7E227