Farmed animals may have positive lives now or in a few decades?

The views expressed here are my own, not those of my employers or reviewers of the draft.

Summary

  • I investigate whether farmed animals may have positive lives now or in a few decades. My results suggest the following:

    • Have negative lives. Hens in conventional cages, broilers in a conventional scenario, and decapod shrimp on an ongrowing farm.

    • May have negative or positive lives. Hens in cage-free aviaries, and broilers in a reformed scenario.

  • I would say at least chickens’ lives can become positive over the next few decades in some animal-friendly countries.

  • I am quite uncertain about the time when farmed animals of a given species will have positive lives in a certain region, if ever. To minimise the risk of decreasing the welfare of farmed animals, I think one should prioritise:

    • Improving the living conditions of farmed animals over decreasing the number of farmed animals with supposedly negative lives.

    • Learning more about:

      • The welfare of farmed animals by species and region.

      • The timeline of the effect of interventions aiming to decrease the number of farmed animals.

Introduction

In my mind, decreasing the number of farmed animals is only good if it increases welfare. This could be achieved by:

  • Making the lives of farmed animals less negative or more positive.

  • Decreasing the number of farmed animals with negative lives.

  • Increasing the number of farmed animals with positive lives.

I recently updated my guess for the intensity of disabling pain to a value 10 % as high as before, and Julian Jamison had noted that relatively small changes to some previous guesses of mine for pain intensities could make farmed animals have positive instead of negative lives, which I agreed with. In this post, I investigate whether farmed animals may have positive lives now or over the next few decades.

Relatedly, see:

Methods

Overview

I estimate the welfare in animal quality-adjusted life years (AQALYs) adding that from pain and pleasure.

I compute the welfare from pleasure from the product between:

  • The lifetime minus 8 h/​d of null welfare minus the sum of the time in hurtful, disabling and excruciating pain.

  • The intensity of hurtful pain.

I calculate the (negative) welfare from pain from the negative of the sum of the contributions of the 4 categories of pain defined by the Welfare Footprint Project (WFP), annoying, hurtful, disabling and excruciating pain. I determine each of the contributions from the product between:

  • The intensity of the pain as a fraction of that of a fully healthy life.

  • Time in the pain in years.

I also express the welfare from pain as a fraction of the lifetime. The welfare as a fraction of the lifetime would be 1 AQALY/​year for the practically maximally happy life[1].

Pain intensity

I rely on 2 sets of pain intensities:

  • My guesses that:

    • Annoying pain is 10 % as intense as fully healthy life, such that 10 days (= 10.1) of annoying pain neutralise 1 day of healthy life.

    • Hurtful pain is as intense as fully healthy life.

    • Disabling pain is 10 times as intense as fully healthy life.

    • Excruciating pain is 100 k times as intense as fully healthy life.

  • Means of lognormal distributions with 5th and 95th percentiles equal to the lower and upper bounds of Laura Duffy’s guesses[2]. According to the means:

    • Annoying pain is 1.45 % as intense as fully healthy life (5th to 95th percentile, 1 % to 2 %).

    • Hurtful pain is 16.4 % as intense as fully healthy life (10 % to 25 %).

    • Disabling pain is 5.04 times as intense as fully healthy life (2 to 10).

    • Excruciating pain is 98.6 times as intense as fully healthy life (60 to 150).

The assumptions for the pain intensities imply each of the following individually neutralise 1 day of fully healthy life:

  • For my assumptions:

    • 10 days of annoying pain.

    • 1 day of hurtful pain.

    • 2.40 h (= 2410) of disabling pain.

    • 0.864 s (= 24*60^2/​(100*10^3)) of excruciating pain.

  • For Laura’s assumptions:

    • 69.0 days (= 10.0145) of annoying pain.

    • 6.10 days (= 10.164) of hurtful pain.

    • 4.76 h (= 245.04) of disabling pain.

    • 14.6 min (= 24*60/​98.6) of excruciating pain.

Time in pain and lifetime

For the time in pain and lifetime:

  • For broilers in a conventional or reformed scenario, I use data from WFP.

  • For hens in a conventional cage or cage-free aviary, I use data from WFP.

  • For decapod shrimp on an ongrowing farm with air asphyxiation, ice slurry or electrical stunning slaughter, I use data from Rethink Priorities (RP), and some assumptions for the 1st and 3rd of those slaughter methods.

Results

My pain intensities

AnimalHen in a conventional cageHen in a cage-free aviaryBroiler in a conventional scenarioBroiler in a reformed scenarioShrimp on an ongrowing farm with air asphyxiation slaughterShrimp on an ongrowing farm with ice slurry slaughterShrimp on an ongrowing farm with electrical stunning slaughter
Welfare for my pain intensities (AQALY)-1.22-0.178-0.1576.62*10^-4-2.76-1.39-1.32
Welfare for my pain intensities as a fraction of the lifetime (AQALY/​year)-0.908-0.133-1.290.00432-8.77-4.40-4.19
Welfare as a fraction of the lifetime relative to that of the worst conditions085.3 %0100 %049.8 %52.3 %

Laura’s pain intensities

AnimalHen in a conventional cageHen in a cage-free aviaryBroiler in a conventional scenarioBroiler in a reformed scenarioShrimp on an ongrowing farm with air asphyxiation slaughterShrimp on an ongrowing farm with ice slurry slaughterShrimp on an ongrowing farm with electrical stunning slaughter
Welfare for Laura’s pain intensities (AQALY)-0.272-0.0149-0.0296-0.003630.01120.01290.0130
Welfare for Laura’s pain intensities as a fraction of the lifetime (AQALY/​year)-0.203-0.0111-0.243-0.02370.03570.04090.0412
Welfare as a fraction of the lifetime relative to that of the worst conditions094.5 %090.3 %014.6 %15.3 %

Discussion

Farmed animals may have positive lives

Now?

My results suggest the following:

  • Have negative lives. Hens in conventional cages, broilers in a conventional scenario, and decapod shrimp on an ongrowing farm.

  • May have negative or positive lives. Hens in cage-free aviaries, and broilers in a reformed scenario.

I have not accounted for other animals linked to the ones I analysed, such as the male chicks linked to hens, and breeders linked to hens and broilers. Nevertheless, I do not know whether the other animals have higher/​lower welfare per lifetime than the ones I analysed, so it is unclear to me whether they make it easier/​harder to reach neutrality. In any case, I do not expect the other animals to change the overall picture that much. For:

  • Hens:

    • I guess the welfare from pain per male chick life is less than 10 % that per hen life.

  • Broilers:

    • I calculate the number broiler breeders killed per year in the European Union (EU) is 0.800 %[3] (= 60*10^6/​(7.5*10^9)) of the number of broilers for consumption killed there per year.

    • Broilers in a conventional scenario “in the EU and the US” live for “42 and 47 days”, i.e. roughly 6.36 weeks (= (42 + 47)/​2/​7). Broiler breeders live “55–62 weeks”, i.e. around 58.5 weeks (= (55 + 62)/​2), or 9.20 (= 58.5/​6.36) times as long as broilers in a conventional scenario.

    • From the 2 points above, I infer there are 7.36 % (= 0.00800*9.20) as many broiler breeders as broilers for consumption.

    • Supposing the welfare from pain per lifetime is 2 times as high for broiler breeders as for broilers for consumption, which I take to be pessimistic because breeders live longer, the welfare from pain linked to broilers would increase by 14.7 % (= 0.0736*2).

Over the next few decades?

Even if one is certain a given population has negative lives now, decreasing it could still be bad if it prevents the existence of positive lives in the future. I believe this possibility is often overlooked. For example:

  • I did not discuss it when I listed a bunch of effects of decreasing the number of farmed animals.

    • The closest I got was saying I did not know whether some populations of animals have positive/​negative lives, thus being uncertain about the value of decreasing their consumption.

  • James Özden did not cover it in the posts Theories of Change for the animal advocacy movement and The default trajectory for animal welfare means vastly more suffering.

    • These seemingly assume that decreasing factory-farming is necessarily good, which may not hold if the lives of farmed animals become positive in the future.

    • I think the posts are great anyways! They are among my favourite high-level posts about animal welfare.

There would be no concern if one targeted decreasing populations of farmed animals whose lives are and will for the next few decades continue to be robustly negative. However, I believe this is unclear even now for chickens in improved conditions. It is also worth having in mind that Open Philanthropy, the main funder of both cage-free and broiler welfare campaigns, only started supporting these in 2016, i.e. just 8 years (= 2024 − 2016) ago. So I would say at least chickens’ lives can become positive over the next few decades in some animal-friendly countries, like ones in the EU, the United Kingdom, and the United States. The same may apply to other species[4].

As a side note, I suppose the slower egg production of hens in cage-free aviaries, and slower growth of broilers in a reformed scenario may end up being doubly beneficial if they eventually transition to systems where they have positive lives. In this case, besides resulting in higher welfare per chicken-year, they would lead to a larger population of chickens with positive lives. In contrast, if hens and broilers still have negative lives in the improved conditions, one has to ensure the increase in welfare per chicken-year is larger than the increase in population for the change to be beneficial in the nearterm.

Consequences given uncertainty

I am quite uncertain about the time when farmed animals of a given species will have positive lives in a certain region, if ever. There is also huge uncertainty about which wild animals have positive/​negative lives, and how their population sizes are affected by changes in the number of farmed animals. To minimise the risk of decreasing the welfare of farmed animals, I think one should prioritise:

  • Improving the living conditions of farmed animals over decreasing the number of farmed animals with supposedly negative lives.

    • For instance, supporting corporate campaigns and welfare laws/​standards over dietary change.

    • If one insists in supporting interventions aiming to decrease the number of farmed animals with supposedly negative lives, I believe ones targeting nearterm decreases are preferable, because I guess farmed animals are more likely to have positive lives in the future. I am not confident investments in alternative proteins are beneficial given their long time horizons.

  • Learning more about:

    • The welfare of farmed animals by species and region, expanding the research of WFP by determining the time spent in the 4 categories of pleasure they defined (satisfaction, joy, euphoria and bliss), and investigating pain and pleasure intensities (relatedly).

    • The timeline of the effect of interventions aiming to decrease the number of farmed animals.

I strongly endorse expected total hedonistic utilitarianism, but I imagine the above conclusions are reinforced by moral uncertainty. Improving the conditions of animals necessarily increases both total and per capita animal welfare (holding the number of animals constant), whereas decreasing the number of animals with negative lives only necessarily increases total animal welfare (holding the conditions constant), and there are moral theories which care about welfare per capita (holding total welfare constant).

Acknowledgements

Thanks to Derek Shiller for feedback on the draft.

  1. ^

    The welfare per time of the practically maximally happy life is much lower than that of the maximally happy instant.

  2. ^

    Laura was executive research coordinator at Rethink Priorities from June 2022 to November 2023.

  3. ^

    “Annually about 7,500 million broilers are reared in the EU27. To produce these broilers about 60 million broiler breeders are required.”

  4. ^

    It is hard to tell, as I am not aware of data on the time spent in pain by species besides chickens in improved conditions. For reference, WFP is working on projects on fish and pigs.