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.
• Now:
  • For my guesses for pain intensities, I think all the farmed animals I analysed have negative lives.

  • For Laura Duffy’s guesses for pain intensities^[1], I guess the following farmed animals:

    • May have positive/negative lives. Hens in cage-free aviaries, broilers in a reformed scenario, and decapod shrimp on an ongrowing farm with air asphyxiation, ice slurry or electrical stunning slaughter.

    • Have negative lives. Hens in conventional cages, and broilers in a conventional scenario.

• In the next few decades, I am open to at least chickens’ lives becoming positive 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 in a few decades.

Relatedly, see:

• Moritz Stumpe's Lives not worth living?.
• Christoph Hartmann's Are Organically Farmed Animals Already Living a Net-Positive Life?.

Methods

Overview

I estimate the (negative) welfare from pain in animal quality-adjusted life years (AQALYs) 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^[2].

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 (= 1/0.1) 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’s guesses. 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 (= 24/10) of disabling pain.
  • 0.864 s (= 24*60^2/(100*10^3)) of excruciating pain.
• For Laura’s assumptions:
  • 69.0 days (= 1/0.0145) of annoying pain.
  • 6.10 days (= 1/0.164) of hurtful pain.
  • 4.76 h (= 24/5.04) 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

Laura’s pain intensities

Discussion

Farmed animals may have positive lives

Now?

I do not think so. For my pain intensities, that would require a seemingly overly high welfare from pleasure for chickens, and impossibly high for decapod shrimp. For the farmed animals in improved conditions to have positive lives, the welfare from pleasure as a fraction of the lifetime would have to be higher than:

• For hens in cage-free aviaries, 0.638 AQALY/year.
• For broilers in a reformed scenario, 0.459 AQALY/year.

• For decapod shrimp on an ongrowing farm with electrical stunning slaughter, 4.85 AQALY/year^[3].

Nonetheless, possibly so for Laura’s pain intensities. These require apparently surpassable welfare from pleasure to neutralise the lives of chickens in improved conditions, and decapod shrimp in the worst conditions:

• For hens in cage-free aviaries, 0.0940 AQALY/year.
• For broilers in a reformed scenario, 0.100 AQALY/year.
• For decapod shrimp on an ongrowing farm with air asphyxiation slaughter, 0.0736 AQALY/year.

I expect more welfare from pleasure than the suggested just above would be needed to reach positive lives due to the time actually spent in pain being longer. WFP’s estimates for the time hens in conventional cages, and broilers in a conventional scenario spend in pain are “conservative”, and so might be RP’s estimates for decapod shrimp on an ongrowing farm with ice slurry slaughter. All in all, for Laura’s pain intensities, I guess the following farmed animals:

• May have positive/negative lives. Hens in cage-free aviaries, broilers in a reformed scenario, and decapod shrimp on an ongrowing farm with air asphyxiation, ice slurry or electrical stunning slaughter.
• Have negative lives. Hens in conventional cages, and broilers in a conventional scenario.

I have not accounted for other animals linked to the ones I analysed, such as the male chicks linked to hens, and broiler breeders linked to 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 %^[4] (= 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).

In a 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 high confidence about this is not warranted even now for Laura’s pain intensities, and not in a few decades for both my and Laura’s pain intensities. My results imply welfare improvements can result in large reductions in pain as a fraction of the lifetime:

• For my pain intensities, when:
  • A hen goes from a conventional cage to a cage-free aviary, 46.4 % (= (-0.638 - (-1.19))/1.19).
  • A broiler goes from a conventional to a reformed scenario, 71.3 % (= (-0.459 - (-1.60))/1.60).
  • A shrimp goes from an ongrowing farm with:
    • Air asphyxiation slaughter to one with electrical stunning, 48.6 % (= (-4.85 - (-9.44))/9.44).
    • Ice slurry slaughter to one with electrical stunning, 4.34 % (= (-4.85 - (-5.07))/5.07).
• For Laura’s pain intensities, when:
  • A hen goes from a conventional cage to a cage-free aviary, 62.4 % (= (-0.0940 - (-0.250))/0.250).
  • A broiler goes from a conventional to a reformed scenario, 66.0 % (= (-0.100 - (-0.294))/0.294).
  • A shrimp goes from an ongrowing farm with:
    • Air asphyxiation slaughter to one with electrical stunning, 7.34 % (= (-0.0682 - (-0.0736))/0.0736).
    • Ice slurry slaughter to one with electrical stunning, 0.292 % (= (-0.0682 - (-0.0684))/0.0684).

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, despite my best guess that all the farmed animals I analysed have negative lives, I am open to at least chickens’ lives becoming positive in 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^[5].

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.

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. ^{^}

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

2. ^{^}

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

3. ^{^}

    Higher than the value of 1 AQALY/year for a maximally practically happy life.

4. ^{^}

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

5. ^{^}

    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.