That’s an interesting and important question (especially rebouncing on the evidence problem discussions), but I also believe that a few concepts were mixed up in this train of thought. Meghann’s comment went above and beyond to answer all of it already, so I’ll just share what I think are the most important take-home messages and what is most convincing (to me):
- Shrimp nociceptors, if categorized by analogy as C- or A- type receptors, most likely ressemble C-types neurons (although, as said, there are no such classification yet). It would thus be more accurate to say that shrimps possess only C-type nociceptors rather than not at all (again, by analogy only). - Stunning is supposed to cause an immediate loss of consciousness, ideally not causing any pain. As explained, it should cause a huge burst of neuron activation in the entire nervous system, not just active nociceptive / pain pathways. Its goal is to make subsequent cold shock death insensibly. Pain could likely arise if animals are able to recover partially. Again, if it was shown that protocols are poorly done (poor stun, recovery, not cold enough water, etc), then yes, it’s possible that SWP interventions could produce more harm than good (or at least not less). However, if the intervention does reduce suffering in ideal-enough conditions (which seems to be the case when looking at the little early evidence that we have), then it is part of the intervention to make sure that the ideal-enough conditions are met to ensure that the protocol stands true to its promises; which SWP does, as far as I know.
-> Thus, if asphyxiation does produce suffering the way you describe it (I know nothing about this stuff), then it would probably induce way more suffering than stunning followed by asphyxiation (or cold shock).
Also, by analogy again, I think we have pretty good evidence that stunning mammals before slaughter allows to reduce suffering. I don’t know the literature, but since so much pigs are slaughtered in CO2 gas chambers suffocating, as well as so many lab mice, I guess we have some insights into how they live through asphyxiation (?). Either way, there is indeed a lack of evidence in shrimps (and invertebrates generally) on the exact way their nervous system works, but the evidence that we have suggests that its not that different than mammals to a point where these kind of experiences may be completely opposites; especially regarding nociception, which is quite relatively well conserved across the entire animal kingdom. Again, I may be completely wrong, and should be told if I am—but I share Meghann’s views on the literature.
That’s an interesting and important question (especially rebouncing on the evidence problem discussions), but I also believe that a few concepts were mixed up in this train of thought. Meghann’s comment went above and beyond to answer all of it already, so I’ll just share what I think are the most important take-home messages and what is most convincing (to me):
- Shrimp nociceptors, if categorized by analogy as C- or A- type receptors, most likely ressemble C-types neurons (although, as said, there are no such classification yet). It would thus be more accurate to say that shrimps possess only C-type nociceptors rather than not at all (again, by analogy only).
- Stunning is supposed to cause an immediate loss of consciousness, ideally not causing any pain. As explained, it should cause a huge burst of neuron activation in the entire nervous system, not just active nociceptive / pain pathways. Its goal is to make subsequent cold shock death insensibly. Pain could likely arise if animals are able to recover partially. Again, if it was shown that protocols are poorly done (poor stun, recovery, not cold enough water, etc), then yes, it’s possible that SWP interventions could produce more harm than good (or at least not less). However, if the intervention does reduce suffering in ideal-enough conditions (which seems to be the case when looking at the little early evidence that we have), then it is part of the intervention to make sure that the ideal-enough conditions are met to ensure that the protocol stands true to its promises; which SWP does, as far as I know.
-> Thus, if asphyxiation does produce suffering the way you describe it (I know nothing about this stuff), then it would probably induce way more suffering than stunning followed by asphyxiation (or cold shock).
Also, by analogy again, I think we have pretty good evidence that stunning mammals before slaughter allows to reduce suffering. I don’t know the literature, but since so much pigs are slaughtered in CO2 gas chambers suffocating, as well as so many lab mice, I guess we have some insights into how they live through asphyxiation (?). Either way, there is indeed a lack of evidence in shrimps (and invertebrates generally) on the exact way their nervous system works, but the evidence that we have suggests that its not that different than mammals to a point where these kind of experiences may be completely opposites; especially regarding nociception, which is quite relatively well conserved across the entire animal kingdom. Again, I may be completely wrong, and should be told if I am—but I share Meghann’s views on the literature.