This is addressed in my recent post.

That study has several substantial flaws discussed in my 2023 study. It substantially underestimates the environmental impacts of pet food. This is partly discussed in my recent post.

re: "the scale as presented in Knight (2023) is inflated based on his ABP calcs"

Readers should be aware that this is an unsubstantiated claim. My recent post has more information on this topic.

re: "I am also a bit skeptical of anything saying cats can be vegan..." 

This is a common concern by those new to this issue. These can help: 

https://sustainablepetfood.info/faqs/, https://sustainablepetfood.info/vegetarian-feline-diets/#3. 

Pets (and people) need nutrients, not ingredients. They require a nutritionally sound diet. They do not require meat.

Some of the other comments I address in my recent post.

This is addressed in my most recent post. Thank you for partly correcting your post. Your criticisms in your point (3) are applicable to your point (4).

Thank you Ben for your acknowledgement that you misrepresented my methodology. This is appreciated. I acknowledge that the calculations can be difficult to understand at first pass. I'll do my best to help anyone struggling to understand them or any other aspects of my methodology or results, and am available for this here. I've addressed some of your comments in my most recent post.

Thanks everyone for the ongoing interest in my studies. Due to workload I'm very short on time so will provide collated responses to various points. I may not have time to comment further in which case my apologies.

• Commentators on the initial post made a series of claims about my recent study. Several were strong claims, negative claims, and false claims. This certainly did not demonstrate “good faith”, but quite the contrary. In light of this my rebuttals were indeed appropriate. A number of the criticisms they responded to, were not. 

• I acknowledge that my calculations determined the number of average farmed animals (being weighted averages of the various species used) that are actually consumed by the different dietary groups (dogs, cats, humans). These calculations of actual consumption were as correct as the data allowed and can be verified by examination of the relevant studies. E.g. within the US in 2020 (as likely also true of other high pet owning nations), 20% of all farmed land animals were consumed by dogs and cats, rather than people. These numbers were then used as proxies for the numbers of farmed land animals that would be spared from slaughter, were nutritionally sound vegan (or cultivated meat-based) diets used instead. This is reasonable, on the face of it. e.g. if dogs consume 2 million farmed land animals annually, then switching those dogs to nutritionally sound vegan diets would prima facie (i.e. on the face of it), spare 2 million farmed land animals from slaughter annually. However, I accept that the actual effects of such a change could differ from the prima facie outcome, depending on effects on the demand and supply of animal-based ingredients in other (non dog food) sectors. Those who wish to argue that something other than the prima facie outcome would occur, face the burden of providing the reasoning and data to demonstrate and quantify this. This could be extremely complex to determine, if sufficient data could be sourced at all, and was well beyond the scope of my studies. I acknowledge that this could be possible however. My study built on others previously as described above, to provide the most accurate figures so far, but these are certainly not a perfect representation of reality. Maybe a future study will extend this work further, by managing to demonstrate how the real world might deviate from the prima facie outcome. Even if such deviations occur, however, I think the results would still show that billions of farmed land animals are killed annually to feed pet dogs and cats. Hence my point about the enormous scale of this problem, and the potential benefits offered by a large-scale transition to nutritionally sound vegan pet diets, would almost certainly remain valid. Additionally, as noted, my calculations were also quite conservative. There were several major and minor estimations made within my studies, that in general probably underestimated the true consumption levels of pets compared to people. Perhaps some of these might also be made more precise in future studies.

• My claims about tractability come from the most comprehensive studies to date (Dodd et al., Mace et al.), which collectively surveyed thousands of dog and cat guardians. These were not perfect (surveys can usually be critiqued) but provide the best data currently available on this issue. As noted above, my study claims re tractability are also quite conservative. My study calculated that at least 150 million dogs and cats worldwide could be transitioned onto nutritionally sound vegan diets. However, this assumed only a single dog or cat per household. In fact, many households have more than one, and so the true numbers of dogs and cats who could be transitioned are substantially higher. Furthermore, conservative percentages of pet carers open to vegan diets were used, which were far lower than those reported in another large-scale survey discussed within this section. Additionally, awareness of vegan pet diets is likely to be much higher today than when these surveys were conducted (before 2019, and in 2020).

As noted, I have a very heavy animal advocacy workload. Unfortunately this means I don't normally have time to follow or contribute to discussion fora, which is a shame as like many of you I expect, I find EA discussions extremely interesting. However, if any reader is genuinely struggling to understand any point within the relevant studies or calculations, rather than simply seeking to undermine these studies (e.g. by making negative and false claims as occurred in the initial post https://forum.effectivealtruism.org/posts/aQzD87AErAvhEdQqi/is-ea-sleeping-on-making-dogs-and-cats-vegan?utm_campaign=post_share&utm_source=link), then I’ll do my best to explain the relevant points. Such readers are welcome to contact me.