Nutritional analysis of commercially available, complete plant- and meat-based dry dog foods in the UK

Rebecca A. Brociek; Dongfang Li; Richard Broughton; David S. Gardner

doi:10.1371/journal.pone.0328506

Peer Review History

Original SubmissionMarch 11, 2025
12 May 2025 Decision Letter - Ewa Tomaszewska, Editor PONE-D-24-48404Nutritional analysis of commercially available, complete plant- and meat-based dry dog foods in the UKPLOS ONE Dear Dr. Gardner, Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process. Please submit your revised manuscript by Jun 26 2025 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org . When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file. 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The PLOS ONE style templates can be found at https://journals.plos.org/plosone/s/file?id=wjVg/PLOSOne_formatting_sample_main_body.pdf and https://journals.plos.org/plosone/s/file?id=ba62/PLOSOne_formatting_sample_title_authors_affiliations.pdf 2. Thank you for stating the following in the Competing Interests section: [DSG conducts nutritional analysis for one of the tested companies’ foods. D.S.G is not involved in the formulation of the food, nor has influence on the design or reporting of results. Since completing the analysis, R.A.B has purchased shares in the same company; testing was completed before this occurred]. Please confirm that this does not alter your adherence to all PLOS ONE policies on sharing data and materials, by including the following statement: ""This does not alter our adherence to PLOS ONE policies on sharing data and materials.” (as detailed online in our guide for authors http://journals.plos.org/plosone/s/competing-interests). 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If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice. [Note: HTML markup is below. Please do not edit.] Reviewers' comments: Reviewer's Responses to Questions Comments to the Author 1. Is the manuscript technically sound, and do the data support the conclusions? The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented. Reviewer #1: Yes Reviewer #2: Yes ******** 2. Has the statistical analysis been performed appropriately and rigorously? Reviewer #1: Yes Reviewer #2: Yes ****** 3. Have the authors made all data underlying the findings in their manuscript fully available? The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified. Reviewer #1: Yes Reviewer #2: Yes ****** 4. Is the manuscript presented in an intelligible fashion and written in standard English? PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here. Reviewer #1: Yes Reviewer #2: Yes ******** 5. Review Comments to the Author Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters) Reviewer #1: 1. Respectfully should read respectively line 7, para1 page 14 2. Page 22 para 1 line 15 Reword the following to remove word churlish “It is almost churlish to propose, therefore, that for all foods designated as ‘complete,’ an assigned nutritional minimum for all essential and conditionally-essential amino acids should at least be followed” 3. I think this reference should be dated 2021 not 2022. Also, these Guidelines have now been updated in 2024. FEDIAF. 2022. "Nutritional guidelines for complete and complementary pet food for cats and dogs." In. http://www.fediaf.org/self-regulation/nutrition.html. Reviewer #2: Thank you for your interesting study, and helping to advance this field. I’ve recommended Minor revisions. Major point The conclusions that supplementation of plant-based diets should be considered—whereas this is usually not suggested for the other diets—is a little unbalanced, as (i) only a very small sample of dry, UK plant-based diets were assessed (so the claim may not be true of plant-based diets generally—anywhere, as it is currently worded, e.g. in the Abstract – this is partially acknowledged in the Conclusions), and (ii) similar suggestions concerning supplementation should be made for the other diets types also found to be deficient. This balance should be redressed where plant-based diets (only) are currently singled out as warranting supplementation. It should be more prominently noted for context (where deficiencies or supplementation are described, including the Abstract), that varying nutritional deficiencies and imbalances are common across most diet types (including non-plant based, ie meat-based diets), and indeed that in this study no foods were found to be without flaws (e.g. “No food met FEDIAF guidelines for all nutrients.”) Minor points Introduction Para 1 citation should be corrected to Vegan Society. Discussion Add citation to end of 1st sentence to https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0291791 References There are 2 references for the Vegan Society. They appear incomplete and inconsistently formatted. Tables To improve readability consider boldfacing all p<0.05 (as well as ) and adding a note to that effect. Table 2 Fe Mg The Col. 1 values are very different from those for all diets – are these figs correct? Table 2 notes: Should [mg/µg] g per 1000kcal be mg or µg per 1000kcal Table 3 For total B-vits, make clearer you’re referring to vits B1-B6, B9 & B12 (as 1-6, 9+12 is not clear) ******* 6. PLOS authors have the option to publish the peer review history of their article (what does this mean? ). If published, this will include your full peer review and any attached files. If you choose “no”, your identity will remain anonymous but your review may still be made public. Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy . Reviewer #1: Yes: Mike Davies Reviewer #2: No ******** [NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". 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Revision 1
22 May 2025 Author Response Reviewer Comments: Reviewer #1 1. Respectfully should read respectively line 7, para1 page 14 Changed. Page 7 line 7 2. Page 22 para 1 line 15 Reword the following to remove word churlish “It is almost churlish to propose, therefore, that for all foods designated as ‘complete,’ an assigned nutritional minimum for all essential and conditionally-essential amino acids should at least be followed” Removed. Page 15 line 15 3. I think this reference should be dated 2021 not 2022. Also, these Guidelines have now been updated in 2024. Updated reference to current (2024). Page 8 line 21 Reviewer #2 Thank you for your interesting study, and helping to advance this field. I’ve recommended Minor revisions. Thank you to the reviewer for your kind words, in an often unkind arena. We have responded to your comments in turn below. Comment: supplementation of plant-based foods. We note your points and have modified the text accordingly, in places (see marked-up red). I do not think it would come as any surprise that vegetarian/vegan pet foods, in line with plant-based human dietary patterns, would be low in some B-vits and iodine. These were consistent in all our, albeit small, sample of plant-based foods. Thus, we suggest that certain supplementation could be considered, without side effects. For the other diets, then isolated – but not consistent – deficiencies were noted (e.g. some essential amino acids in renal foods) and we have noted the overall lack of compliance throughout the manuscript, including the discussion. Indeed, we do agree with your point and have modified the text accordingly. To do: It should be more prominently noted for context (where deficiencies or supplementation are described, including the Abstract), that varying nutritional deficiencies and imbalances are common across most diet types (including non-plant based, ie meat-based diets), and indeed that in this study no foods were found to be without flaws (e.g. “No food met FEDIAF guidelines for all nutrients.” Para 1 citation should be corrected to Vegan Society Changed Page 3, line 5 Add citation to end of 1st sentence added References It is how endnote formats non-standard references. Will try to alter, but can do after the fact by hand. Tables Readability hopefully improved. Table 2 Yes, values for iron and magnesium as mgs per 1000kcal according to FEDIAF 2024 are indeed 9.00 and 0.18 (mgs per 1000 kcal ME), respectively. Page 16 of 98 in FEDIAF 2024. Table 2 notes: Yes, have altered to improve readability Table 3 Added ‘B’ to make clearer Attachments Attachment Submitted filename: Rebuttal to revews 13-05-2025.docx https://doi.org/10.1371/journal.pone.0328506.r002
5 Jun 2025 Decision Letter - Ewa Tomaszewska, Editor PONE-D-24-48404R1Nutritional analysis of commercially available, complete plant- and meat-based dry dog foods in the UKPLOS ONE Dear Dr. Gardner, Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process. Please submit your revised manuscript by Jul 20 2025 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org . When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file. Please include the following items when submitting your revised manuscript: A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'. A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'. An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'. If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter. If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: https://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols . Additionally, PLOS ONE offers an option for publishing peer-reviewed Lab Protocol articles, which describe protocols hosted on protocols.io. Read more information on sharing protocols at https://plos.org/protocols?utm_medium=editorial-email&utm_source=authorletters&utm_campaign=protocols . We look forward to receiving your revised manuscript. Kind regards, Ewa Tomaszewska, DVM Ph.D Academic Editor PLOS ONE Journal Requirements: Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice. [Note: HTML markup is below. Please do not edit.] Reviewers' comments: Reviewer's Responses to Questions Comments to the Author 1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation. Reviewer #2: (No Response) ******** 2. Is the manuscript technically sound, and do the data support the conclusions? The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented. Reviewer #2: Yes ****** 3. Has the statistical analysis been performed appropriately and rigorously? Reviewer #2: Yes ****** 4. Have the authors made all data underlying the findings in their manuscript fully available? The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified. Reviewer #2: Yes ****** 5. Is the manuscript presented in an intelligible fashion and written in standard English? PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here. Reviewer #2: Yes ****** 6. Review Comments to the Author Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters) Reviewer #2: Thank you for addressing all my previous suggestions. My only remaining suggestion is to review boldfacing applied in tables where p < 0.05. A very few instances where p < 0.05 seem to have been missed. ****** 7. PLOS authors have the option to publish the peer review history of their article (what does this mean? ). If published, this will include your full peer review and any attached files. If you choose “no”, your identity will remain anonymous but your review may still be made public. Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy . Reviewer #2: No ******** [NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.] While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/ . PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org . Please note that Supporting Information files do not need this step. https://doi.org/10.1371/journal.pone.0328506.r003
Revision 2
25 Jun 2025 Author Response i have made bold the three instances in tables, as suggested by reviewer #002. No other changes requested. Attachments Attachment Submitted filename: Rebuttal to revews 06-06-2025.docx https://doi.org/10.1371/journal.pone.0328506.r004
2 Jul 2025 Decision Letter - Ewa Tomaszewska, Editor Nutritional analysis of commercially available, complete plant- and meat-based dry dog foods in the UK PONE-D-24-48404R2 Dear Dr. David S. Gardner, We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements. Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication. An invoice will be generated when your article is formally accepted. Please note, if your institution has a publishing partnership with PLOS and your article meets the relevant criteria, all or part of your publication costs will be covered. Please make sure your user information is up-to-date by logging into Editorial Manager at Editorial Manager® and clicking the ‘Update My Information' link at the top of the page. If you have any questions relating to publication charges, please contact our Author Billing department directly at authorbilling@plos.org. If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org. Kind regards, Ewa Tomaszewska, DVM Ph.D Academic Editor PLOS ONE Additional Editor Comments (optional): Reviewers' comments: https://doi.org/10.1371/journal.pone.0328506.r005
Formally Accepted
Acceptance Letter - Ewa Tomaszewska, Editor PONE-D-24-48404R2 PLOS ONE Dear Dr. Gardner, I'm pleased to inform you that your manuscript has been deemed suitable for publication in PLOS ONE. Congratulations! Your manuscript is now being handed over to our production team. At this stage, our production department will prepare your paper for publication. This includes ensuring the following: * All references, tables, and figures are properly cited * All relevant supporting information is included in the manuscript submission, * There are no issues that prevent the paper from being properly typeset You will receive further instructions from the production team, including instructions on how to review your proof when it is ready. Please keep in mind that we are working through a large volume of accepted articles, so please give us a few days to review your paper and let you know the next and final steps. Lastly, if your institution or institutions have a press office, please let them know about your upcoming paper now to help maximize its impact. If they'll be preparing press materials, please inform our press team within the next 48 hours. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org. You will receive an invoice from PLOS for your publication fee after your manuscript has reached the completed accept phase. If you receive an email requesting payment before acceptance or for any other service, this may be a phishing scheme. Learn how to identify phishing emails and protect your accounts at https://explore.plos.org/phishing. If we can help with anything else, please email us at customercare@plos.org. Thank you for submitting your work to PLOS ONE and supporting open access. Kind regards, PLOS ONE Editorial Office Staff on behalf of Professor Ewa Tomaszewska Academic Editor PLOS ONE https://doi.org/10.1371/journal.pone.0328506.r006

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