Hi Vasco, I’m not sure Food Impacts is calculating things correctly. They start off by calculating the number of animal hours lived to create 2,000 calories, which is reasonable. The next step should be to multiply that number by the average welfare of an animal, since that should tell you how many negative welfare units would be averted by not creating the demand for 2,000 calories.
But instead, they multiply by the welfare range of the animal.
This doesn’t make sense to me. If a farmed cow’s actual welfare is −0.1, why does it matter that its welfare range is −0.25 to 0.25? To figure out how much negative welfare I can avert, I care about the −0.1!
Am I thinking about this correctly?
And if so, is there a good resource for actual welfare values for farmed animals, rather than the theoretical ranges?
And if so, is there a good resource for actual welfare values for farmed animals, rather than the theoretical ranges?
I have estimated the welfare per living time of chickens in various conditions in animal quality-adjusted life years (AQALYs) per chicken-year. 1 AQALY corresponds to 1 year of a practically maximally happy life. As a rough approximation, you can get the welfare in QALYs mutiplying the welfare in AQALYs by Rethink Priorities’ median welfare ranges[1].
Animal
Broiler in a conventional scenario
Broiler in a reformed scenario
Hen in a conventional cage
Hen in a cage-free aviary
Welfare per living time (AQALY/year)
-2.27
-0.161
-1.69
-0.333
I have some estimates for shrimp too (this post has estimates for chickens, but these rely on underestimates of the time they spend in pain, whereas the ones above try to correct for this).
This would only be 100 % correct if the welfare per time of the practically maximally happy life as a fraction of the welfare range is constant across species.
As a rough approximation, you can get the welfare an QALYs mutiplying the welfare in AQALYs by Rethink Priorities’ median welfare ranges
I might be misunderstanding something, but I’m not sure that’s right, even with your footnote. My understanding is that animal AQALYs per years and human QALYs per year both range from +1 at the top, to some species-specific negative value at the bottom. The same is true of the Rethink welfare units, but with a different scale. If so, shouldn’t the formula be as described below?
This would only be 100 % correct if the welfare per time of the practically maximally happy life as a fraction of the welfare range is constant across species.
In this case, “maximum welfare of a chicken-year”/(“maximum welfare of a chicken-year”—“minimum welfare of a chicken-year”) = “maximum welfare of a human-year”/(“maximum welfare of a human-year”—“minimum welfare of a human-year”) ⇔ “maximum welfare of a chicken-year” = (“maximum welfare of a chicken-year”—“minimum welfare of a chicken-year”)/(“maximum welfare of a human-year”—“minimum welfare of a human-year”)*”maximum welfare of a human-year”. Since “welfare range of chickens” = (“maximum welfare of a chicken-year”—“minimum welfare of a chicken-year”)/(“maximum welfare of a human-year”—“minimum welfare of a human-year”), “maximum welfare of a chicken-year” = “1 AQALY in chickens”, and “maximum welfare of a human-year” = “1 QALY”, “1 AQALY in chickens” = “welfare range of chickens”*”1 QALY”. So, given the condition I mentioned in the footnote, one can get the welfare in QALYs mutiplying the welfare in AQALYs by the welfare range.
Hi Vasco, I’m not sure Food Impacts is calculating things correctly. They start off by calculating the number of animal hours lived to create 2,000 calories, which is reasonable. The next step should be to multiply that number by the average welfare of an animal, since that should tell you how many negative welfare units would be averted by not creating the demand for 2,000 calories.
But instead, they multiply by the welfare range of the animal.
This doesn’t make sense to me. If a farmed cow’s actual welfare is −0.1, why does it matter that its welfare range is −0.25 to 0.25? To figure out how much negative welfare I can avert, I care about the −0.1!
Am I thinking about this correctly?
And if so, is there a good resource for actual welfare values for farmed animals, rather than the theoretical ranges?
Thanks for the comment, Chris!
Yes.
I have estimated the welfare per living time of chickens in various conditions in animal quality-adjusted life years (AQALYs) per chicken-year. 1 AQALY corresponds to 1 year of a practically maximally happy life. As a rough approximation, you can get the welfare in QALYs mutiplying the welfare in AQALYs by Rethink Priorities’ median welfare ranges[1].
I have some estimates for shrimp too (this post has estimates for chickens, but these rely on underestimates of the time they spend in pain, whereas the ones above try to correct for this).
This would only be 100 % correct if the welfare per time of the practically maximally happy life as a fraction of the welfare range is constant across species.
Thanks Vasco,
I might be misunderstanding something, but I’m not sure that’s right, even with your footnote. My understanding is that animal AQALYs per years and human QALYs per year both range from +1 at the top, to some species-specific negative value at the bottom. The same is true of the Rethink welfare units, but with a different scale. If so, shouldn’t the formula be as described below?
In this case, “maximum welfare of a chicken-year”/(“maximum welfare of a chicken-year”—“minimum welfare of a chicken-year”) = “maximum welfare of a human-year”/(“maximum welfare of a human-year”—“minimum welfare of a human-year”) ⇔ “maximum welfare of a chicken-year” = (“maximum welfare of a chicken-year”—“minimum welfare of a chicken-year”)/(“maximum welfare of a human-year”—“minimum welfare of a human-year”)*”maximum welfare of a human-year”. Since “welfare range of chickens” = (“maximum welfare of a chicken-year”—“minimum welfare of a chicken-year”)/(“maximum welfare of a human-year”—“minimum welfare of a human-year”), “maximum welfare of a chicken-year” = “1 AQALY in chickens”, and “maximum welfare of a human-year” = “1 QALY”, “1 AQALY in chickens” = “welfare range of chickens”*”1 QALY”. So, given the condition I mentioned in the footnote, one can get the welfare in QALYs mutiplying the welfare in AQALYs by the welfare range.
Got it, thanks. For those following along at home, I misread your footnote and the graphs I made do not reflect the condition in the footnote.
If it makes things easier, you can copy the Google Slides source to tweak the illustration https://docs.google.com/presentation/d/1LuSpONztS9Tl0OSn-YeyWJG7B6UIYtff49p1WREPPgA/edit#slide=id.p