PONE-D-25-45259

Efficient timed mating and early pregnancy detection in guinea pigs

PLOS ONE

Dear Dr. Mass,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we have decided that your manuscript does not meet our criteria for publication and must therefore be rejected.

I am sorry that we cannot be more positive on this occasion, but hope that you appreciate the reasons for this decision.

Kind regards,

Kathleen R. Pritchett-Corning, D.V.M.

Academic Editor

PLOS ONE

Additional Editor Comments:

This paper is surprisingly derivative of a cited work, that of Wilson et al. This issue goes beyond normal citation practices and represents a fundamental mischaracterization of the work's originality, as the authors present as novel . The vaginal cytology and qPCR sperm detection protocols are worth publishing. However, this manuscript, as currently written, does not provide sufficient novel contribution to warrant publication as an independent protocol. The manuscript might work if reframed as "Validation and refinement of the Wilson et al. protocol with earlier pregnancy detection and vaginal cytology." The authors likely did not intend to misrepresent their work, but the current presentation could mislead readers about the protocol's origins and the authors' contributions to the field.

[Note: HTML markup is below. Please do not edit.]

Reviewer's Responses to Questions

Comments to the Author

?>

Reviewer #1: No

**********

2. Has the protocol been described in sufficient detail?-->?>

Reviewer #1: No

**********

3. Does the protocol describe a validated method??>

Reviewer #1: No

**********

4. If the manuscript contains new data, have the authors made this data 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.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: No

**********

5. Is the article presented in an intelligible fashion and written in standard English?

Reviewer #1: Yes

**********

Reviewer #1: The manuscript by Mayer et al. presents a laboratory protocol for timed mating and early pregnancy detection in guinea pigs, aimed at facilitating their use in developmental research. The authors describe methods for estrous cycle monitoring, mating timing, qPCR detection of sperm and ultrasound-based pregnancy detection as early as embryonic day 12. While the protocol addresses practical challenges faced by researchers using guinea pig models, the authors need to address the inadequate acknowledgment of prior work and questionable originality.

This manuscript presents a protocol that is strikingly similar to the previously published work by Wilson et al. (2021, Methods Protoc. 4, 58) - reference 19 in the current manuscript. While Wilson et al. is cited, the authors fail to adequately acknowledge that they are essentially reproducing an existing, well-established protocol rather than developing a novel methodology. Both protocols use identical approaches: vaginal membrane monitoring for estrous cycle tracking, the same mating timing strategy, and ultrasound confirmation of pregnancy. The figures showing vaginal membrane changes are remarkably similar in concept and presentation. The authors present their work as if they independently developed these methodologies ("Here, we present a standardized protocol") rather than clearly stating they are adapting/validating an existing protocol. This raises serious concerns about the originality and added value of the current manuscript. The authors must either: (a) clearly reframe this as a validation/adaptation study of the Wilson et al. protocol with appropriate prominent acknowledgment throughout (remove the vaginal membrane monitoring and time-mating procedures and and simply reference the Wilson et al. 2021), or (b) demonstrate substantial novel contributions that justify publication as an independent protocol.

Additionally, the authors need to clarify the inconsistent pregnancy detection claims via ultrasound. The abstract claims pregnancy detection "as early as embryonic developmental day 12 (E12)" but the methods section mentions this wasn't consistently achieved. The authors state "while direct visualization of embryos or placental tissues may be challenging" at E12, which contradicts the confident claims in the abstract. The reliability and success rate of E12 detection across different operators and equipment also needs clarification.

Minor comment: Line 67 "other studies suggest that reliable detection is not possible before E20 (19,21)." Reference 19 actually states "In our experience, an ultrasound is the only definitive method for determining a pregnancy prior to gestational day 30 (Figure 4), but is limited to not being accurate before gestational day 21". Not that it cannot be done. Reference 21 is a paper from 1986 and ultrasound technology is vastly superior now than back then. Please correct.

**********

what does this mean?). If published, this will include your full peer review and any attached files.). If published, this will include your full peer review and any attached files.). If published, this will include your full peer review and any attached files.). 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 For information about this choice, including consent withdrawal, please see our For information about this choice, including consent withdrawal, please see our For information about this choice, including consent withdrawal, please see our Privacy Policy..-->

Reviewer #1: 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.]

- - - - -

For journal use only: PONEDEC3

Validation and refinement of existing methods for timed mating and early pregnancy detection in guinea pigs

PONE-D-25-45259R1

Dear Dr. Mass,

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. For questions related to billing, please contact  and clicking the ‘Update My Information' link at the top of the page. For questions related to billing, please contact  and clicking the ‘Update My Information' link at the top of the page. For questions related to billing, please contact  and clicking the ‘Update My Information' link at the top of the page. For questions related to billing, please contact billing support....

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,

Muhammad Zubair

Academic Editor

PLOS One

Additional Editor Comments (optional):

There is no novelty in this manuscript and authors represent mischaracterization of the work's originality, as the authors present as novel

Comments from PLOS Editorial Office: PLOS One is designed to communicate original research and research methods. Novelty is not a criteria for publication on PLOS One.

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

?>

Reviewer #1: No

**********

2. Has the protocol been described in sufficient detail??>

To answer this question, please click the link to protocols.io in the Materials and Methods section of the manuscript (if a link has been provided) or consult the step-by-step protocol in the Supporting Information files.

Reviewer #1: Yes

**********

3. Does the protocol describe a validated method??>

Reviewer #1: Yes

**********

4. If the manuscript contains new data, have the authors made this data 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.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

**********

5. Is the article presented in an intelligible fashion and written in standard English?

Reviewer #1: Yes

**********

Reviewer #1: The authors have addressed the comments from the first review. I have nothing further to add.

**********

what does this mean?). If published, this will include your full peer review and any attached files.). If published, this will include your full peer review and any attached files.). If published, this will include your full peer review and any attached files.). 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 For information about this choice, including consent withdrawal, please see our For information about this choice, including consent withdrawal, please see our For information about this choice, including consent withdrawal, please see our Privacy Policy..-->

Reviewer #1: No

**********