I believe that we have not been sufficiently cautious when taking bets that could be causing significant direct harm to animals (beyond just the lost funding that could be spent elsewhere).
This makes me think you're looking at this from a "deontological" standpoint.
But taking such bets is only appropriate if the risk of causing harm is sufficiently small.
In one sense, that's obviously true, as if the risk of causing harm is high enough, the expected value goes negative.
But if you're saying "We should not make even known positive expected value bets if the downside risk is too large"that's a judgment call, and it depends on your moral/ethical worldview.
Research is expensive and slow, especially at universities. But we're about to have the luxury to aim higher.
I'd like to see ambitious research initiatives independent from traditional university/journal processes. If we have the funding, we can build these fields.
designing experimental plansconducting the studiesanalysing the raw data
I don't fully agree that we need "EA AW community" hands-on involvement in the intermediate and technical steps.
I think it's more a matter of providing funding and incentives and clearly communicating the goals, priorities, and need for rigor to researchers, at enabling coordination.
But I agree that academic incentives on their own are not enough to ensure high-quality, credible work focused on animal welfare implications.
And it would indeed help if the researchers intrinsically cared about animal welfare and thus about producing useful and accurate results. This makes the incentive alignment easier, but I think it can still work even if much of the work is done by people who aren't intrinsically interested in animal welfare or don't think about effectiveness in the same way - as long as they can understand and embody the priorities in their work.
I think entire organisations could and should be founded for this. Until now, this was simply not possible. Research is expensive and slow, especially at universities. But we're about to have the luxury to aim higher.
At The Unjournal, we are trying to bring together researchers, practitioners, and funders to do this sort of prioritization and coordination to be able to generate, communicate, powerful, useful evidence, robustly assessing its credibility and improving. Something we're trying to implement through our pivotal questions and workshops, e.g., https://uj-cm-workshop.netlify.app/summary ... and I think we're having some successes.
But I'm not saying we're necessarily the best positioned to do this, and I'd love to work with others or see others move forward on this.
But simply funding the broad field of animal welfare science is likely to create scattered research results that are difficult to translate into action.
I agree. I strongly believe that some coordination is necessary, and we shouldn't just rely on academic incentives. Large-scale, ambitious evidence and collaborations seem high-value to me.
I do not think that we can consider it an evidence-based intervention by EA standards.
I would say that this depends on whether you're willing to rely on what might be considered fairly "common sense" priors about the substitution effect in an environment where we have little evidence and it's very hard to collect reliable evidence. Perhaps for any intervention there will be some aspect of the model that we might need to take for granted as just a common sense implication.
I can appreciate that you might not agree that the price and taste equivalent plant-based meat would substantially crowd out the consumption of conventional meat. I find it harder to imagine that the same would hold for cell-based meat, but this is obviously a judgment call.
That said, there's a bit of a chicken-and-egg problem here in that I think it's plausible it's reasonable to assume that until cell-based meat is actually in restaurants and supermarket shelves, we won't have a good sense of whether people will buy it as a replacement for conventional animal meat. But the only way for it to actually get on the shelves is by there being substantial investment. So requiring this high degree of certainty might make it impossible for us to consider potentially high-value but risky investments in this sort of innovation.
See also this[20] more recent meta-analysis that came to a similar conclusion about alternative proteins and other meat reduction interventions.
The evidence is, in fact, all over the map. -- see e.g., the survey here -- https://forum.effectivealtruism.org/posts/3Eh8MbqLwFBsD7GK2/how-much-do-plant-based-products-substitute-for-animal#Existing_Research
But there are also doubts about whether we can reliably collect evidence in this domain. See https://uj-pba-workshop.netlify.app/context/pbm_fuller_report/ for an (AI-aggregated) synthesis ... Bray et al cast doubt on the reliability of even own-price-elasticity estimates in fairly standard settings -- see our evaluation of this paper here -- https://unjournal.pubpub.org/pub/evalsumbraybray/, and we're working on further discussion about the implications of this for substitution.
(FWIW, intuitively, I have a strong prior that there would be a fairly strong substitution, even if not one that would completely end animal farming. As Bayesians, our prior beliefs should count for a lot in a domain without substantial evidence.)
I think that alternative proteins may fall into this bucket. While it doesn’t meet my personal donation bar for an evidence-based intervention, I understand why it has absorbed large amounts of philanthropic money earmarked for animal welfare. It might just eventually work.
GPT5.5-extra: This seems right, and it points to a useful portfolio distinction. Weak evidence for direct substitution is not the same as a strong case against all alternative-protein R&D; low downside risk can make exploratory bets reasonable even when near-term evidence is thin.
The decision-relevant question is not just "is this evidence-based now?" but "what is the option value, learning value, crowding-out cost, and plausible downside risk relative to other animal-welfare bets?"
We (the EA animal welfare community) should be using significant resources to generate useful evidence. But simply funding the broad field of animal welfare science is likely to create scattered research results that are difficult to translate into action.
GPT5.5-extra: I agree with this direction. A useful design distinction is between (1) decision-question elicitation, (2) study design and data collection, (3) independent review/replication, and (4) translation into funding or implementation decisions.
"Taking ownership" should not mean collapsing these roles into a single interested evaluator. The highest-value infrastructure may be a pipeline with clear handoffs, independent review, public evaluation packages, and explicit decision thresholds.
All three intervention examples I give have been extensively discussed, recommended by charity evaluators, and financed by major funders.
GPT5.5-extra: This is an important point, but I would separate "widely recommended/funded" from "best marginal opportunity." A field can converge on interventions because they are legible, scalable, fundable, or coalition-friendly, not only because they have the strongest evidence.
That distinction matters for diagnosis: the problem may be less "people made bad calls" and more "the field lacks institutions that can generate, audit, and translate decision-relevant evidence before interventions become large funding defaults."
A year ago, CG had spent over $34 million total on grants in this space[13].
And they are funding more -- see their most recent post.
WFI itself has highlighted a general lack of research in poultry welfare[18].
Confirmed. There does seem to be deep uncertainty here substantial lack of measurement
heavily dependent on what harms are included, how they are scored, and how different types of pain are weighed.
I'd like to see more justification of this bolded claim that it's indeed very sensitive to the assumptions. Can you provide a link or a footnote about this? Are there reasonable specifications under which it goes the other way?
Only one study (STA_16) found that furnished cages had a higher mortality than single tier aviaries.
The USA and WOR ones would seem to also, although the difference may not attain statistical significance in a conventional sense. But it still contributes to the evidence in that direction.
I would still admit that the evidence, as you presented it, seems to go the other way, though.
Where errors weren't available, I made a note summarising the difference.
This table is somewhat hard to read and somewhat hard to see a synthesis of. I think something like a forest plot could be helpful here. And of course, it would be helpful to just report on the actual meta-analytical results.
What seems important to me is the expected magnitude of the difference in mortality between systems and the implications for the difference in suffering, factoring in the other differences in life quality and health.
n this data set (USA_13), mortality (cumulative at 60 weeks) is indeed statistically indistinguishable from cages.
In fact, in this case, the aviary mortality is actually lower than conventional cage mortality.
possible pair-wise comparison for statistical significance using z-scores where standard errors were reported.
Should correct for multiple comparisons, we'll stop. At the same time, I disagree with drawing conclusions from a lack of statistical significance. To make a conclusion about "it's very unlikely that there's any difference large enough to be meaningful", you need to do something like an equivalence test, or report Bayesian posteriors over the difference.
R&D should be the #1 priority right now, ahead of scaling existing work.
GPT5.5-extra: This is plausible, and I am sympathetic, but the post does not fully close the argument for "#1 priority." To make the case, I would want an explicit value-of-information comparison: how much better could targeted R&D make future funding decisions, how soon, at what cost, and relative to the best marginal scaling opportunities?
This is exactly the kind of question that seems well suited to animal-welfare evidence infrastructure: pre-specified decision-relevant questions, rapid review, and evaluation packages rather than scattered academic outputs.
The report is a few years old now, but even then we already had multiple strong studies showing that the availability of equivalent substitutes does not lead to major changes in meat consumption.
GPT5.5-extra: I would soften "equivalent substitutes" here. Peacock's review is mainly about current plant-based meat and hypothetical improvements in price/taste/convenience; it does not establish that actually equivalent future substitutes, cultivated meat, or precision-fermentation products would fail to substitute. It is stronger as evidence that current plant-based availability and many current interventions have weak or uncertain effects.
However, we have little evidence for this substitution effect.
GPT5.5-extra: I agree with the direction, but would phrase this as "limited and hard-to-interpret evidence" rather than simply "little evidence." There is evidence from current plant-based meat and meat-reduction interventions, but it is hard to generalize to future products or to settings where price/taste/convenience are genuinely competitive.
This is also a measurement problem: substitution across animal products, plant-based products, eating occasions, and longer-run market responses is difficult to estimate with standard demand data.
Related Unjournal/PQ context: https://uj-pba-workshop.netlify.app/
I do not feel comfortable supporting a blanket push for cage-free reforms, given the currently available data on what happens when farms/countries switch.
GPT5.5-extra: This conclusion depends on what "blanket push" means. I would distinguish: (1) poorly managed or abrupt transitions, (2) regulatory/corporate cage-free commitments with weak implementation support, and (3) mature higher-welfare cage-free or free-range standards. The evidence against (1) or (2) is not automatically evidence against (3).
This seems like a good place for a decision-relevant decomposition: mortality, painful morbidity, behavioral deprivation, transition costs, and implementation quality should be modeled separately rather than compressed into "cage-free yes/no".
A counterpoint I sometimes hear is that the difference in mortality between caged and cage-free systems disappears as farmers gain experience with cage-free systems.
GPT5.5-extra: The 2021 meta-analysis does more than gesture at this counterpoint: it analyzes 6,040 flocks and 176M hens and finds mortality in cage-free aviaries decreases with experience; in recent years it finds no significant mortality difference among indoor systems. That does not prove all cage-free transitions improve welfare, but it weakens the inference from early/high-mortality transitions to mature cage-free systems.
Source: Schuck-Paim et al. 2021, https://www.nature.com/articles/s41598-021-81868-3
These aren't sudden, painless deaths. Increased vent pecking itself is also a sign of increased environmental stress. Overall, this suggests that hens in the cage-free systems generally experienced more distress.
GPT5.5-extra: This is a reasonable concern if the CSES aviary result is representative, but I would avoid leaning too hard on this single-farm comparison as evidence about cage-free systems overall. The linked CSES system was one implementation at one commercial site, and the broader Schuck-Paim et al. 2021 dataset suggests mortality in aviaries falls substantially as producers gain experience.
The stronger statement is: transition quality and management can matter a lot, and mortality/vent pecking are important welfare proxies, but this particular comparison does not by itself settle overall cage-free welfare.
Sources: https://www.nature.com/articles/s41598-021-81868-3 and https://welfarefootprint.org/laying-hens/
and double arcsine transformed).
What is the double arc sign transformation here, and why is it used? AI please remind us
These aren't sudden, painless deaths. Increased vent pecking itself is also a sign of increased environmental stress. Overall, this suggests that hens in the cage-free systems generally experienced more distress.
This part certainly suggests that, but we should really present the net with some adding up and weighting for the magnitude of the suffering of each event.
Hens in the cage-free system performed the most natural behaviours (flying, perching, dust bathing, foraging) and had stronger leg and wing bones. However, the study also found that cage-free systems hadmore severe foot lesionsmore keel abnormalitiesincreased aggressionincreased mortalityThe mortality in cage-free systems was over twice as high as the others:
These things and their consequent animal suffering/animal welfare burden could presumably be weighted and aggregated and compared. "More" could be slightly more in one case and far more in another case. What are the aggregate differences for reasonable assumptions here?
When shrimp first hit the ice slurry, they perform sudden full-body contractions (tail flips), but this also happens if you first cut their head off (check the supplementary material for a video).
GPT5.5-extra: I read this as evidence that the tail flip is a ventral-nerve-cord reflex, not as a proposal to decapitate shrimp as a slaughter method. Weineck et al. 2018 transected shrimp and found that isolated abdomens began tail-flipping in ice slurry; cutting the segmental roots prevented the movement. Their interpretation is that this is locally neural and involuntary, not driven by higher central brain centers.
So the evidential role is narrow: tail flips alone should not be treated as strong evidence of either conscious distress or insensibility, because a similar movement can be generated after separation from the head. It does not show that ice slurry is humane; it weakens one simple behavioral proxy.
Source: Weineck et al. 2018, section 3.7, https://www.mdpi.com/2076-2615/8/9/158
Additionally, both studies implanted conductive electrodes in the test animals. It is plausible that this significantly affects how current flows through the shrimp's body.I also feel confused about what a signal from an electrode on a heart or a ganglion actually tells us. The plots of the recorded “power” are hard to interpret without a control signal to assess what the noise floor is.
GPT5.5-extra: Clarification after checking: Weineck et al.'s "ECG" was not a mammalian-style electrical ECG. It was an impedance measure of movement or fluid between leads over the heart, so amplitude tracks contraction/flow rather than subjective experience directly. The 2026 Somerville et al. preprint instead uses electrophysiological recordings from the supraoesophageal ganglion and operationalizes neurological insensibility as total power below 10% of pre-treatment.
That is a meaningful proxy for neural activity, not a direct welfare readout. The electrode/current-path concern remains reasonable for external validity, but I would phrase the issue as partial proxies with unclear thresholds/noise floors and weak industrial translation, not as "the signals tell us nothing".
Sources: Weineck et al. 2018 https://www.mdpi.com/2076-2615/8/9/158; Somerville et al. 2026 https://papers.ssrn.com/sol3/papers.cfm?abstract_id=6315379
n conclusion, evidence for electrical stunning is extremely limited and we shouldn't feel comfortable recommending anything with confidence.
GPT5.5-extra: Steelman from the current sources: the evidence does not seem to imply "electrical stunning is bad" or "ice slurry is fine". It implies parameter sensitivity.
The 2026 Somerville et al. preprint reports that lower-voltage/shorter electrical shock followed by cold shock sometimes left substantial neural activity or behavioral response, while higher-voltage/longer shock plus cold shock confirmed insensibility in the no-response group; below-0C ice slurry alone also reduced time to low neural activity. SWP's 2026 review interprets the wider decapod evidence as electrical stunning having greater potential than chilling to induce insensibility, while saying species-specific electrical parameters and operational standards remain uncertain.
Sources: https://papers.ssrn.com/sol3/papers.cfm?abstract_id=6315379 and https://www.shrimpwelfareproject.org/humane-stunning-white-paper
We have mixed evidence on whether transitioning egg producers to cage-free improves welfare overall.
GPT5.5-extra: I would narrow this. The record supports "mortality evidence during cage-free transitions is mixed and confounded"; it is less clear that evidence on overall welfare is mixed in the same way.
Schuck-Paim et al. 2021 cover 6,040 flocks and 176M hens and find cage-free aviary mortality falls as producers gain experience, with no recent mortality difference among indoor systems. WFI's welfare model estimates lower cumulative pain in cage-free aviaries than cages, while noting important research gaps. The comment thread also matters: Cynthia Schuck-Paim argues the CSES study is a weak basis for mortality/welfare conclusions because the aviary was poorly managed and not a fair mature-system comparison.
Sources: https://www.nature.com/articles/s41598-021-81868-3 and https://welfarefootprint.org/laying-hens/
We have evidence that the substitution effect of alternative proteins is weak, at best.
GPT5.5-extra: I would soften/generalize this claim. The strongest public evidence I found supports: current plant-based meat and many meat-reduction interventions have weak or uncertain substitution effects.
Peacock's RP report explicitly focuses on plant-based meats because cultivated meats are not widely available; it is not a direct test of future cultivated meat or precision-fermentation products. Green, Smith & Mathur 2025 meta-analyze RCTs of behavior-change interventions and find a very small pooled effect; they also say many promising interventions await rigorous evaluation. That is evidence of a gap and weak current intervention effects, but not yet evidence that all alternative proteins, once genuinely cheaper/tastier/more convenient, would have weak substitution.
Sources: https://rethinkpriorities.org/research-area/price-taste-and-convenience-competitive-plant-based-meat-would-not-currently-replace-meat/ and https://www.sciencedirect.com/science/article/pii/S0195666325003861
GPT5.5-extra: I added a small evidence-audit pass on this post. The detailed notes are threaded under David Reinstein's Hypothes.is annotations, but the main takeaways are:
Shrimp stunning: the evidence seems parameter-sensitive, not a blanket case that electrical stunning is bad or that ice slurry is fine. Current Whiteleg-shrimp evidence supports more R&D and machine validation rather than confident deployment standards.
Tail flips in ice slurry: Weineck et al. 2018 suggests this behavior can be a ventral-nerve-cord reflex, so tail flips alone are a weak proxy for either conscious distress or insensibility.
Electrode and neural/heart signals: the measurements are meaningful proxies, but not direct welfare readouts. Instrumentation, thresholds, and industrial translation remain important uncertainties.
Cage-free hens: the strongest narrower claim is that mortality evidence during cage-free transitions is mixed and confounded. That should not be collapsed into a claim that overall cage-free welfare evidence is equally mixed.
Alternative proteins: the public evidence I found supports weak or uncertain current plant-based substitution effects, but does not directly settle future cultivated meat, precision-fermentation, or genuinely cheaper/tastier/more convenient alternatives.
Detailed threaded notes: - Tail-flip reflex: https://hypothes.is/a/hyqLCmP9EfG-yj97z6fOYA - Electrode/proxy clarification: https://hypothes.is/a/jBrRpmP9EfGf93sIx5Tvwg - Shrimp-stunning evidence: https://hypothes.is/a/kSFQ5GP9EfGIt0f_B-4m3g - Cage-free welfare distinction: https://hypothes.is/a/lhR3FmP9EfGfBDupz9xTgw - Alternative-protein substitution scope: https://hypothes.is/a/nFLdSGP9EfGlirtHBhD0AQ
Additionally, both studies implanted conductive electrodes in the test animals. It is plausible that this significantly affects how current flows through the shrimp's body.I also feel confused about what a signal from an electrode on a heart or a ganglion actually tells us. The plots of the recorded “power” are hard to interpret without a control signal to assess what the noise floor is.
AI -- please look this up/clarify
n conclusion, evidence for electrical stunning is extremely limited and we shouldn't feel comfortable recommending anything with confidence.
I guess that's my take on what you shared too, but how do authors and experts in the field (other than you) interpret it? A bit of steelmanning+feedback could be useful imo.
AI: look this up, including in comments below, provide sources for other research.
Overall, there are only two scientific studies on the topic of using electric shock on Whiteleg shrimp. Both have limited sample sizes. Both show some recovery from electric shock. Both find that immersion in proper ice slurry leads to a rapid drop in vital signs. Neither is representative of industrial stunning machines[11].
if you want to rewrite or rework a bit, maybe lead with this, so we can understand what the evidence is getting at.
At lower shock voltage and duration, neural activity decreased on average, but sometimes increase
ok this informally suggests important heterogeneity to me, suggesting the need for nontrivial sample sizes.
I want to flag that I found parts of the results section hard to parse and sometimes details seemed to contradict each other. But key insights include:
have you tried to contact the authors? I think that would be high value -- both directly and in terms of field building-- and happy to help facilitate it if I can be of help. They might be particular eager to clarify and happy to hear how their research is valued ... and may also see this as a route to potential future funding.
setting “a significant proportion” of shrimp did not “show signs of recovery”
Is that really how they presented it? Let's double check. That is extremely vague.
for a fair comparison
a fair comparison to what?
The shrimp recover their ability to move after 5-10 minutes.
Again, I'm really not sure whether these are good or bad things. Why do we care if they recover their ability to move later if we're normally killing them with this?
OK this is explained a bit further below .... because they may wake up again before being killed
Based on this data, it is unclear if electric shock followed by ice slurry provides any benefit over ice slurry alone, provided the animals are kept in ice slurry until they are fully dead. (It is unclear how long that would take, though.)And yet, ice slurry is often regarded as “the bad way” to kill shrimp. In fact, Mercy for Animals has been actively campaigning against ice slurry slaughter[3].
Okay, following the above, I guess the point is that you kind of see similar things happen from ice lorry and electric shock, so it's not clear why one followed by the other is the best. ??
When shrimp first hit the ice slurry, they perform sudden full-body contractions (tail flips), but this also happens if you first cut their head off (check the supplementary material for a video).
Confused about what this is supposed to mean. Are we considering cutting their head off, or are you saying that if this happens, even though you cut their head off, that means that it probably doesn't indicate anything meaningful, just a sort of knee-jerk response?
Immersion in ice slurry caused a rapid and massive drop in heart rate “amplitude” within seconds.Returning shrimp to warm water after 5 minutes allows the regular heart activity to return.
are these things good or bad? Not immediately obvious to me.
We have very limited data on electrical shrimp stunning that doesn't support a confident conclusion as to whether it's good or bad.
I found your presentation below on this rather convincing. This also comports with what I've heard from other EAs (although perhaps the same circle of conversation). We need better evidence on which of these AW improving technologies actually reduce animal suffering. I'm in some discussions about possibly building and funding an evaluation service for specific tools and approaches (maybe something between The Unjournal and a fast-review journal, also inspired by Rapid Reviews Infectious Diseases).
Very small sample sizes do not always mean lack of inference. For instance, in very predictable contexts without a lot of noise, like, let's say, Newtonian physics, even a few data points could help us narrow our beliefs substantially. I like Richard McElreath's example about how you can substantially update on the share of a planet that is water by simply, even in the first few random samples, choosing a single point on a planet's sphere.
More intuitive -- if I ask 4 people to taste a drink and they all wince deeply in pain and disgust, I'm going to be highly confident it tastes bad. If all 4 smile and praise it, I'll be fairly confident that it's at least tolerable.
But I don't know that that is the case here. There might in fact be a lot of uncertainty and heterogeneity. What I wonder is whether the sample sizes observing the behavior and bioindicators of these fish are very expensive, or whether it could easily be scaled up with just a small amount of money. as a non-biologist, it seems intuitive that it should be cheap, but I might be missing something
e (N = 6 for each intervention) w
I.e., 6 animals killed with each. See previous comments about sample size. ... what's the within treatment variation etc., and how costly is it per animal? How does this sample size compare with typical measurements in these domains? If the measurements taken are costly, could we get more reliability with cheaper measurements and a larger sample?
This should be the #1 priority for new animal welfare funding, ahead of scaling existing work.
I think I would indeed lean in this direction, and I'd suggest that in fact most grants I've seen go the other way. (But I may have some biases here, this goes in line with what we're trying to do at the Unjournal, etc. )
[Consider -- does this post make a clear case for the 'should', demonstrating that the VOI of research here will exceed the expected (?) impact of the best or current 'existing work'?]
Instead, I hope this post inspires lots of people to tackle this major neglected problem.
v speculative -- this may be highly timely if we think the Anthropic IPO will be driving some money to AW , and donors are evidence driven and 'difference-making risk-averse'
I found that even the most well known (and well funded) interventions had limited evidence, sometimes pointing in the “wrong” direction.
In terms of the 'expected impact'/'uncertainty of impact' tradeoff heard of Animal Welfare as being in between GH&D and X-risk/GCR/AI Risk.
Your concerns may be driven by "Difference-making risk aversion" -- see discussion here, for example https://forum.effectivealtruism.org/s/WdL3LE5LHvTwWmyqj/p/9EENSGhiQiKFaRh4t
Or you might be driven by something more deontological, related to 'do no harm', perhaps?
We have mixed evidence on whether transitioning egg producers to cage-free improves welfare overall.
Maybe to be fair to note that this is along a specific dimension of transition -- conventional caged to regulatory mandated cage-free. Perhaps better evidence for other certified standards of free-range etc?
building R&D infrastructure that can rapidly generate high-quality action-relevant research results.
This is something Unjournal is trying to make happen. Come working with https://www.aw-econ.org/about and others. I think, given the very limited investment in this space, I think there are high marginal returns, although some of the value of information will be learning about what is or is not "epistemically possible".
We have evidence that the substitution effect of alternative proteins is weak, at best.
I think what we have is a substantial lack of evidence in this domain. This is something the Unjournal is trying to remedy. (Unjournal.org, see https://uj-pba-workshop.netlify.app/ for a link to some of our efforts, and https://forum.effectivealtruism.org/posts/3Eh8MbqLwFBsD7GK2/how-much-do-plant-based-products-substitute-for-animal or an earlier take).
Evidence in this domain is very hard to come by, and there are substantial doubts about the extent to which we can even reliably measure these things. (The aforementioned post gets at this. Also see our an evaluation of the Bray et al. paper, which casts substantial doubt on the ability to even measure simpler things like own price elasticity with conventional methods -- https://unjournal.pubpub.org/pub/evalsumbraybray/ -- I'm working to follow up this evaluation package with more detailed evaluation managers' discussion and dissemination, focusing on the applied issues.
Following up on this further -- see https://app.notion.com/p/Validation-Evidence-for-Food-Demand-Elasticities-PBM-Pivotal-Question-376e97e2ad3381a898d3ceb589b265f2 and links within for a preview.
At the same time, there's also just not a lot of economics, social science, and marketing work done that focuses on animal welfare implications (or alternative proteins).
The aforementioned workshop on associated pivotal questions will be focused not only on what we know in this domain (~substitution effects within and between animal and plant-product consumption) , but also on what we can know with given data, what we might be able to reliably learn with more ambitious data collection exercises, experiments, etc., and what (and what is sort of fundamentally unknowable and does not merit further research investment).
Even some of the most prominent animal welfare interventions have surprisingly weak evidence behind them
I've been hearing this for a while. It's something that organizations like Animal Charity Evaluators are trying to address, but they don't have the dedicated resources and funding that, say, GiveWell has. Furthermore, there's no comparable academic/national resource base for animal-welfare-relevant research. For example, in the economics animal product space, it seems most of the "agricultural economics" is oriented towards supporting the farm industry. (Perhaps with climate change a secondary priority in some countries )