Thanks for the comment, Tristan.
I agree factory-farmed animals having positive lives is not sufficient to justify continuing factory-farming. If one is confident that i) wild animals have positive lives, ii) the effects of factory-farming on wild animals are much larger than those on farmed animals, and iii) factory-farming decreases the number of wild animals (as animal products usually require more land than plant-based ones), then ending factory-farming would be good to increase animal welfare when accounting for both farmed and wild animals. However, I am not arguing for reaching positive factory-farming, and then maintaining it forever. I am arguing for having the ultimate goal of increasing animal welfare, which I think is robustly good, unlike ending factory-farming or maintaining positive factory-farming forever.
I also think that focussing on increasing the welfare of factory-farmed animals (instead of ending factory-farming) is more conducive to making people care about the welfare of wild animals. People justify ending factory-farming as a way of perserving nature, but I believe this may well backfire because wild animals may have negative lives. There is huge uncertainty about whether wild animals have positive/ānegative lives, so I would say it is more prudent to have the robustly good ultimate goal of increasing welfare.
Thanks, Aaron.
I accounted for badly implemented ice slurry slaughter. I assumed:
In any case, based on my assumptions, it does not matter whether HSI is harmful for the 37.5 % of the affected shrimp which go from well implemented ice slurry to electrical stunning slaughter. The overall cost-effectiveness is dominated by making 62.5 % of the affected shrimp go from air asphyxiation to electrical stunning slaughter. I estimate 97.3 % (= 0.625*0.0447/ā0.0287) of the benefits come from helping shrimp slaughtered via air asphyxiation, and that the increase in welfare for these is 48.6 % (= 1 ā 4.85/ā9.44), whereas the number of shrimp would very hardly increase by that. So the question of whether the number of shrimp increases is only relevant if a very small fraction of the helped shrimp is slaughtered via air asphyxiation (again, conditional on my assumptions).