Type 2 Diabetes Mellitus in a Binturong (Arctictis binturong): A Case Report of Pancreatic Islet Amyloidosis

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

peer Review Report – Manuscript Title: “Type 2 Diabetes Mellitus in a Binturong (Arctictis binturong)”

Recommendation: Major Revision

General Evaluation

The manuscript presents the first documented case of type 2 diabetes mellitus associated with pancreatic islet amyloidosis in a binturong (Arctictis binturong). The topic is novel and within the journal’s scope, contributing new knowledge to zoo and wildlife medicine. However, while the biological observations are interesting, the paper requires major revisions before it can be considered for publication. The most critical issues concern methodological clarity, data completeness, figure quality, adherence to case report guidelines (CARE) or animal reporting standards (ARRIVE 2.0), and language precision.

Below are structured comments by section, divided into Major and Minor issues.

• Major Comments

1. Title and Abstract

-The title should explicitly state that this is a case report to increase discoverability and transparency.
Suggested title:
“Type 2 Diabetes Mellitus in a Binturong (Arctictis binturong): A Case Report of Pancreatic Islet Amyloidosis.”

-The abstract should be rewritten in a structured format (Background, Case Presentation, Results, Conclusions) following CARE guidelines. It must briefly mention:

The diagnostic approach (hyperglycemia + glucosuria + histological confirmation).

The lack of pharmacological treatment.

The key histopathological finding (islet amyloidosis).

The significance of the case (first report in the species).

2. Introduction

-Strengthen the rationale and research gap:

-Explain clearly why diabetes in Arctictis binturong is important beyond being unreported.

-Summarize current knowledge of amyloidosis-related diabetes in other Viverridae species or close taxa (cats, civets).

-Support background claims with recent and authoritative references (e.g., Reusch et al. 2014, Abedini & Schmidt 2013).

-Explicitly state the objective of the case report at the end of the Introduction (e.g., “to describe the clinical, biochemical, and histopathological findings associated with T2DM in a geriatric binturong”).

3. Materials and Methods / Case Description

-Follow CARE / ARRIVE 2.0 reporting standards:

-Add a timeline table or figure summarizing all clinical events, sampling dates, tests, and key findings (Oct 2019 → Dec 2019 → Jun 2020 → Sep 2023 → postmortem).

-Provide detailed animal information: sex, age, weight, diet, housing, environment (temperature, light cycle, enrichment), and veterinary oversight.

-Clarify diagnostic methods and references:

-State exactly which version/date of the ZIMS reference ranges was used (e.g., “accessed November 2, 2024”).

-Explain sampling procedures (e.g., sedation protocol, fasting duration, blood collection site) to account for stress-induced hyperglycemia.

• Histopathology:

-Describe tissue processing and staining in more detail.

-Confirm fixation time, embedding, and staining protocols (H&E, Congo Red, Masson’s Trichrome).

              -Consider performing or at least discussing immunohistochemistry for IAPP (amylin) to confirm the nature of the amyloid deposits.

• Semi-quantitative scoring:

-Include or propose a semi-quantitative histological grading system (e.g., percentage of islet amyloidosis, degree of β-cell loss, peri-islet fibrosis) to improve objectivity.

• Ethical statement:

-Add a sentence clarifying that institutional or ethical approval for reporting zoo animal medical data was obtained or deemed unnecessary.

4. Results

1. Table presentation:
• Improve the readability of Tables 1 and 2. Use larger fonts, better alignment, and highlight abnormal values in bold.
• Include units and reference intervals in the table headers.
2. Data interpretation:
• Discuss whether glucose fluctuations (23.8 → 27.7 → 14.2 → 36.2 mmol/L) are physiologically meaningful or within measurement error.
• Clarify the relationship between biochemical trends and clinical signs (weight loss, tremors, cataracts).
3. Ultrasound findings:
• Add clearer labeling to Figure 1 and specify magnification and scale bars.
• Mention the sonographic parameters (probe frequency, machine settings) for reproducibility.

4. Postmortem Findings / Histopathology

1. Figures:
• Provide high-resolution TIFF or PNG images (≥300 dpi) with clear magnification (e.g., 100×) and scale bars.
• Label figure panels properly (A = H&E, B = Congo Red, etc.) and provide concise, descriptive legends.
2. Amyloid identification:
• While Congo Red birefringence confirms amyloid, add discussion on the absence of IAPP immunostaining and how this limits conclusions regarding β-cell–specific amyloidosis.
• Cite Abedini & Schmidt (2013, FEBS Letters, DOI:10.1016/j.febslet.2013.01.017) for background on IAPP amyloid mechanisms.
3. Quantitative assessment:
• If feasible, provide a semi-quantitative estimate (e.g., percentage of affected islets) to support claims of “diffuse” amyloidosis.

6. Discussion

1. Interpretation and limitations:
• Include a dedicated Limitations paragraph, acknowledging:
• The single-case nature.
• Lack of immunohistochemistry for amyloid typing.
• Potential confounding from advanced age and concurrent diseases (spondylosis, cataracts, renal changes).
• Uncertain renal glucose threshold in this species.
2. Comparative discussion:
• Expand discussion comparing this case with known T2DM in cats, non-human primates, and other viverrids.
• Clarify how these findings might contribute to developing diagnostic or preventive strategies in zoo animals.
3. Therapeutic considerations:
• Discuss more deeply the reasoning for not using hypoglycemic treatment and reference existing trials in wildlife or exotic mammals (e.g., metformin in callitrichids, Strike & Feltrer 2017).

7. Figures and Tables

 

1. Figures must meet publication-quality standards:
• Replace all placeholder or low-resolution figures.
• Add scale bars, magnification, and clear labels.
• Ensure figure numbering matches the text.
2. Merge histological images (A–E) into one composite plate with a shared scale bar for consistency.

8. References

Major Comments

1. Reformat all references according to MDPI citation style.
2. Verify that:
• Reference #5 (year 2025) is correct and not a typographical error.
• Journal names are consistently included.
3. Include relevant methodological references (ARRIVE 2.0, CARE checklist).
4. Remove duplicate or redundant citations.
5. Check DOI formatting and accessibility.

 

9. Language and Formatting

-The manuscript requires professional English editing for grammar, syntax, and clarity. There are multiple awkward phrases and inconsistent tenses.

-Standardize units (mmol/L, µmol/L, etc.).

-Ensure consistent spacing and punctuation.

 

• Minor Comments

1. Title and Abstract

-Ensure abbreviations (T2D, IAPP) are defined upon first mention.

-Avoid overstatements such as “first ever in wildlife” unless verified by systematic review.

2. Introduction

-Check all references for accuracy and consistent citation style.

-Correct capitalization of species names (Arctictis binturong italicized).

3. Materials and Methods / Case Description

 

-Provide full manufacturer details for all diagnostic kits and analyzers (model, city, country).

-Correct “20 years and 8 months” (postmortem section) to ensure internal consistency with earlier age reporting.

-Replace any file path references in figure legends (e.g., “D:...”) with clean captions.

4. Results

-Use consistent terminology for clinical signs (avoid redundancy such as “hyperglycemia (high glucose)”).

-Correct minor typographical inconsistencies (“5 Dec 2019” vs “December 5, 2019”).

 

5. Postmortem Findings / Histopathology

-Clarify all abbreviations in figure legends (e.g., “CV = central vein”, “PA = pancreatic acini”).

-Avoid overlapping or blurred image panels.

 

6. Discussion

-Avoid overly general phrases like “highlighting the difficulties” — be precise about which diagnostic or management aspects were difficult.

-Maintain tense consistency (use past tense for all case observations).

7. Figures and Tables

-Simplify figure legends by removing unnecessary narrative details.

-Ensure all tables/figures are cited in order within the text.

I have no major ethical concerns regarding the conduct of the study. However, I recommend that the authors explicitly state compliance with institutional or ethical approval for animal data use, as required by journal policy (e.g., confirmation that zoo medical records were used under institutional permission).

 

Author Response

General Evaluation

The manuscript presents the first documented case of type 2 diabetes mellitus associated with pancreatic islet amyloidosis in a binturong (Arctictis binturong). The topic is novel and within the journal’s scope, contributing new knowledge to zoo and wildlife medicine. However, while the biological observations are interesting, the paper requires major revisions before it can be considered for publication. The most critical issues concern methodological clarity, data completeness, figure quality, adherence to case report guidelines (CARE) or animal reporting standards (ARRIVE 2.0), and language precision.

Below are structured comments by section, divided into Major and Minor issues.

• Major Comments

1. Title and Abstract

-The title should explicitly state that this is a case report to increase discoverability and transparency.
Suggested title:
“Type 2 Diabetes Mellitus in a Binturong (Arctictis binturong): A Case Report of Pancreatic Islet Amyloidosis.”

Authors Reply: Thank you for your comment, the title has been edited as suggested.

-The abstract should be rewritten in a structured format (Background, Case Presentation, Results, Conclusions) following CARE guidelines. It must briefly mention:

The diagnostic approach (hyperglycemia + glucosuria + histological confirmation).

The lack of pharmacological treatment.

The key histopathological finding (islet amyloidosis).

The significance of the case (first report in the species).

Authors Reply: Thank you for your comment. The 2013 CARE guidelines checklist mentions an abstract may be “structured or unstructured”, so we have elected to leave this abstract in its original format. Minor edits have been made to better fulfil the CARE guidelines checklist, including more text on the background of diabetes mellitus (lines 13-16), and reason for importance (lines 25-26). All four points otherwise specified by the reviewer are already explicitly mentioned in the abstract, in the exact sequence suggested. (lines 19, 20, 22, 24-26)

1. Introduction

-Strengthen the rationale and research gap:

-Explain clearly why diabetes in Arctictis binturong is important beyond being unreported.

Authors Reply: Thank you for your comments, an additional paragraph has been added in the introduction to discuss the long term health implications of T2D, and the critical need to understand the presentations/risk factors and management considerations (both husbandry and medicinal) (lines 70-76).

-Summarize current knowledge of amyloidosis-related diabetes in other Viverridae species or close taxa (cats, civets).

Authors Reply: A sentence has been added into the introduction to discuss this (lines 60-62). There is no existing published literature on amyloidosis-related diabetes in Viverridae, with the exception of two individuals diagnosed with DM mentioned in a large-scale review in the United States. No further discussion is mentioned in that publication, and it is unknown if islet amyloidosis was noted or played a role in those two individuals, or a different mechanism altogether.

-Support background claims with recent and authoritative references (e.g., Reusch et al. 2014, Abedini & Schmidt 2013).

Authors Reply: Further references have been added to support the additional statements made.

-Explicitly state the objective of the case report at the end of the Introduction (e.g., “to describe the clinical, biochemical, and histopathological findings associated with T2DM in a geriatric binturong”).

Authors Reply: The final paragraph of the introduction has been rephrased accordingly (lines 78-79).

1. Materials and Methods / Case Description

-Follow CARE / ARRIVE 2.0 reporting standards:

-Add a timeline table or figure summarizing all clinical events, sampling dates, tests, and key findings (Oct 2019 → Dec 2019 → Jun 2020 → Sep 2023 → postmortem).

Authors Reply: Thank you for your comment. A timeline figure has been included (captioned Figure 1) at the beginning of the Materials and Methods/Case Description section.

-Provide detailed animal information: sex, age, weight, diet, housing, environment (temperature, light cycle, enrichment), and veterinary oversight.

Authors Reply: Thank you for your comment. The age and sex of the animal are already mentioned. A short section (lines 97-102) has been added to the beginning of the case description briefly detailing the animal’s husbandry.

-Clarify diagnostic methods and references:

-State exactly which version/date of the ZIMS reference ranges was used (e.g., “accessed November 2, 2024”).

Authors Reply: Respectfully, this is already clearly specified in line 118.

-Explain sampling procedures (e.g., sedation protocol, fasting duration, blood collection site) to account for stress-induced hyperglycemia.

Authors Reply: Thank you for your comment. Additional lines specifying the sedation protocol and blood collection process of the animal has been included (lines 106 – 112).

• Histopathology:

-Describe tissue processing and staining in more detail.

-Confirm fixation time, embedding, and staining protocols (H&E, Congo Red, Masson’s Trichrome).

Authors Reply: Respectfully, we feel this to be excessive and outside of the scope of this report. An instructional on trimming, processing, embedding, cutting, and performing H&E/Congo Red staining is atypical in published case reports and will only serve to clutter the report. A basic level of knowledge on these established processes is expected of the target audience.

-Consider performing or at least discussing immunohistochemistry for IAPP (amylin) to confirm the nature of the amyloid deposits.

Authors Reply: Thank you for your comment, this is a good point. A line clarifying that IHC was not performed due to cost and logistical restrictions has been added (line 214-216). The lack of immunohistochemistry performed in this patient, and the resulting limitations have been added in the discussion section (lines 241-257).

• Semi-quantitative scoring:

-Include or propose a semi-quantitative histological grading system (e.g., percentage of islet amyloidosis, degree of β-cell loss, peri-islet fibrosis) to improve objectivity.

Authors Reply: Thank you for your comment. A subjective grade (~70% of islets affected by amyloidosis noted in the cut section in histology) has been added to the results section (line 212-213).

• Ethical statement:

-Add a sentence clarifying that institutional or ethical approval for reporting zoo animal medical data was obtained or deemed unnecessary.

Authors Reply: Thank you for your comment. An ethics statement has been included in lines 183-186 and under the Institutional Review Board Statement (line 349-353)

1. Results

1. Table presentation:
• Improve the readability of Tables 1 and 2. Use larger fonts, better alignment, and highlight abnormal values in bold.
• Include units and reference intervals in the table headers.

 

Authors Reply: Thank you for your comment. The font size used (10) is reproduced as per the word template provided by the journal and so has not been changed. The authors further note that figures in the journal template are aligned to the centre. We have however justified all figures to the left to improve readability as per the reviewer’s recommendations.

 

Please refer to Tables 1 and 2 again, as abnormal values are already highlighted in bold. Units and reference intervals are already clearly included in table headers.

 

1. Data interpretation:
• Discuss whether glucose fluctuations (23.8 → 27.7 → 14.2 → 36.2 mmol/L) are physiologically meaningful or within measurement error.
• Clarify the relationship between biochemical trends and clinical signs (weight loss, tremors, cataracts).

 

Authors Reply: The significance of the clinical signs observed, their potential links to uncontrolled diabetes mellitus, and confounding conditions that may also result in such signs are extensively discussed in the discussion section of the manuscript.

 

1. Ultrasound findings:
• Add clearer labeling to Figure 1 and specify magnification and scale bars.
• Mention the sonographic parameters (probe frequency, machine settings) for reproducibility.

 

Authors Reply: Figure 1 edited with scale bar inserted. Minor edits have been included (lines 124-126), specifying the probe used. The specific machine settings such as frequency and gain were unavailable, though such a level of detail could typically be considered outside the scope of this paper and dependent on the operator’s approach.

 

1. Postmortem Findings / Histopathology

1. Figures:
• Provide high-resolution TIFF or PNG images (≥300 dpi) with clear magnification (e.g., 100×) and scale bars.
• Label figure panels properly (A = H&E, B = Congo Red, etc.) and provide concise, descriptive legends.

 

Authors Reply: Thank you for your comment. The relevant figures have been corrected with visible scale bars and the correct resolution. Caption for Figure 3 has had minor edits (line 225-226) to improve brevity.

 

1. Amyloid identification:
• While Congo Red birefringence confirms amyloid, add discussion on the absence of IAPP immunostaining and how this limits conclusions regarding β-cell–specific amyloidosis.
• Cite Abedini & Schmidt (2013, FEBS Letters, DOI:10.1016/j.febslet.2013.01.017) for background on IAPP amyloid mechanisms.

 

Authors Reply: See above response regarding the absence of immunohistochemical analysis and the new section added. The background on IAPP amyloid mechanisms is already explicitly detailed in this paper, already citing the exact source recommended by the reviewer.

 

1. Quantitative assessment:
• If feasible, provide a semi-quantitative estimate (e.g., percentage of affected islets) to support claims of “diffuse” amyloidosis.

 

Authors Reply: See above response.

 

1. Discussion

1. Interpretation and limitations:
• Include a dedicated Limitations paragraph, acknowledging:
• The single-case nature.
• Lack of immunohistochemistry for amyloid typing.
• Potential confounding from advanced age and concurrent diseases (spondylosis, cataracts, renal changes).
• Uncertain renal glucose threshold in this species.

Authors Reply: Thank you for your comment. A dedicated limitations paragraph has been added to the discussion section, discussing the single-case nature of the report and lack of immunohistochemistry (lines 241-257). Potential confounding factors (lines 276 onwards) and the uncertain renal glucose threshold (line 265-266) are already discussed extensively in the manuscript.

 

1. Comparative discussion:
• Expand discussion comparing this case with known T2DM in cats, non-human primates, and other viverrids.
• Clarify how these findings might contribute to developing diagnostic or preventive strategies in zoo animals.
2. Therapeutic considerations:
• Discuss more deeply the reasoning for not using hypoglycemic treatment and reference existing trials in wildlife or exotic mammals (e.g., metformin in callitrichids, Strike & Feltrer 2017).

 

Authors Reply: The reasoning for not using hypoglycemic treatments in wildlife/exotic species is adequately discussed at length in the manuscript (lines 308-325). The exact reference suggested here by the reviewer is already clearly cited in line 315.

 

1. Figures and Tables

1. Figures must meet publication-quality standards:
• Replace all placeholder or low-resolution figures.
• Add scale bars, magnification, and clear labels.
• Ensure figure numbering matches the text.
2. Merge histological images (A–E) into one composite plate with a shared scale bar for consistency.

 

Authors Reply: Minor edits have been made to both figures to include a scale bar, and ensure a resolution of 300 dpi.

 

1. References

Major Comments

1. Reformat all references according to MDPI citation style.

 

Authors Reply: References and citations have been checked according to editor’s instructions.

 

1. Verify that:
• Reference #5 (year 2025) is correct and not a typographical error.
• Journal names are consistently included.

 

Authors Reply: Reference #5 (Rand and Marshall, Diabetes mellitus in cats) is correctly dated as a reference from the year 2005, not 2025. There are no other references throughout the bibliography or in-text that appear to refer to a reference published in 2025.

 

All journal names have already been included, however the citation style has been updated to meet MDPI guidelines and journal name format adjusted accordingly.

 

1. Include relevant methodological references (ARRIVE 2.0, CARE checklist).

 

Authors Reply: Unless we are mistaken, we do not believe the ARRIVE or CARE guidelines need to be referenced in the paper’s bibliography, given they are author guidelines for reporting quality and not a particular scientific source relevant to this paper.

 

1. Remove duplicate or redundant citations.

 

Authors Reply: The paper has been carefully checked for duplicate or redundant citations, and none have been found.

 

1. Check DOI formatting and accessibility.

 Authors Reply: The DOI format has been corrected and appropriate links added for all references in the reference list.

1. Language and Formatting

-The manuscript requires professional English editing for grammar, syntax, and clarity. There are multiple awkward phrases and inconsistent tenses.

Authors Reply: We appreciate the reviewer’s concern, but decline the recommendation for professional English editing. We have revised the manuscript carefully, but note that both the editor and the other reviewers have not identified issues regarding the standard of English. Should the reviewer have further concerns regarding any specific phrases or the use of tenses, we encourage them to clarify which lines they believe require reconsideration.

-Standardize units (mmol/L, µmol/L, etc.).

Authors Reply: We believe the reviewer to be referencing Tables 1 and 2, where units differ between analytes. (e.g. mmol/L for BUN, µmol/L for Creatinine). Respectfully, we disagree that these units should be standardized here for the sake of it. The units provided reflect the conventions for each assay as reported by the analyser for readability. Converting all values to a single unit will produce unwieldy and unconventional values such as reporting 23860 µmol/L of glucose, rather than 23.86mmol/L and vice versa. The units have been left as originally intended.

-Ensure consistent spacing and punctuation.

Authors Reply: The manuscript has been checked to ensure consistent spacing and punctuation. We encourage the reviewer to make use of the line numbers to clarify areas in which they find inconsistencies.

• Minor Comments

1. Title and Abstract

-Ensure abbreviations (T2D, IAPP) are defined upon first mention.

Authors Reply: Respectfully, both of these terms are already explicitly spelled in full at first mention in both the abstract (line 13) and main manuscript (line 50, line 230), prior to inclusion of the abbreviation in parentheses. They are also included in the abbreviations list at the end of the manuscript (lines 360 onward).

-Avoid overstatements such as “first ever in wildlife” unless verified by systematic review.

Authors Reply: The use of the word “first” has been removed from the conclusion of the manuscript.

1. Introduction

-Check all references for accuracy and consistent citation style.

Authors Reply: All references within the introduction have been checked for accuracy. We encourage the reviewer to clarify any lines that they believe include inaccuracies or inconsistencies.

-Correct capitalization of species names (Arctictis binturong italicized).

Authors Reply: Thank you for your comment, the latin name ‘Arctictis binturong’ has been italicized where they appear throughout the manuscript (title, line 16, line 32, figure and table captions)

1. Materials and Methods / Case Description

-Provide full manufacturer details for all diagnostic kits and analyzers (model, city, country).

Authors Reply: Please refer to lines 108 to 126. All information requested here has already been provided.

-Correct “20 years and 8 months” (postmortem section) to ensure internal consistency with earlier age reporting.

Authors Reply: The patient’s age in line 95 has been clarified to 16 years and 6 months in order to maintain consistency with the age given at postmortem.

-Replace any file path references in figure legends (e.g., “D:...”) with clean captions.

Authors Reply: There are no file path references noted in any of the figure legends, nor embedded within the images, anywhere in the manuscript submitted. We encourage the reviewer to specify the figure legends in which file path references were noted.

1. Results

-Use consistent terminology for clinical signs (avoid redundancy such as “hyperglycemia (high glucose)”).

Authors Reply: At no point in the manuscript was the phrase “hyperglycemia (high glucose)” used, nor have we noted any similar redundancies on revision of the manuscript. We encourage the reviewer to specify the numbered lines in which inconsistent or redundant terminology was noted.

-Correct minor typographical inconsistencies (“5 Dec 2019” vs “December 5, 2019”).

 Authors Reply: At no point in the manuscript was the date format “December 5, 2019” used for any dates provided. All specific dates given throughout the manuscript and tables consistently follow the format of “5 Dec 2019”. We encourage the reviewer to specify the numbered lines in which minor typographical inconsistencies were noted.

1. Postmortem Findings / Histopathology

-Clarify all abbreviations in figure legends (e.g., “CV = central vein”, “PA = pancreatic acini”).

Authors Reply: No abbreviations were used in any of the figure legends within this manuscript. We encourage the reviewer to specify which abbreviations within the figure legends require clarification, as neither the terms “central vein” nor “pancreatic acini” were used.

-Avoid overlapping or blurred image panels.

 Authors Reply: No overlapping of image panels are noted on careful revision of the manuscript.

1. Discussion

-Avoid overly general phrases like “highlighting the difficulties” — be precise about which diagnostic or management aspects were difficult.

Authors Reply: Thank you for your comment. We believe this comment to refer to line 258, regarding the challenges emphasised in diagnosing diabetes mellitus in zoological species. Respectfully, we believe the specific aspects of the diagnostic process are adequately elaborated on in the subsequent sentences. Namely, the lack of standardized criteria across species (line 259), presumptive nature on the basis of clinical signs and elevated blood/urine glucose (line 260), lack of established biochemical parameters (line 262 and 265), and confounding factors such as stress and renal disease (line 264-265). While the first sentence (line 258) initially appears overly general, this is known as a topic sentence, and serves to summarize the point made within the paragraph for the reader. Subsequent sentences thereafter elaborate the point.

-Maintain tense consistency (use past tense for all case observations).

Authors Reply: Respectfully, we have reviewed the report and have found no inconsistencies in the use of tense. All references made to case observations have been made in simple past tense. We encourage the reviewer to utilize the line numbers of the manuscript to point out specific inconsistencies that require revision.

1. Figures and Tables

-Simplify figure legends by removing unnecessary narrative details.

Authors Reply: Thank you for your comment. The legend for Figure 1 has been rephrased accordingly to improve objectivity and conciseness.

-Ensure all tables/figures are cited in order within the text.

I have no major ethical concerns regarding the conduct of the study. However, I recommend that the authors explicitly state compliance with institutional or ethical approval for animal data use, as required by journal policy (e.g., confirmation that zoo medical records were used under institutional permission).

Authors Reply: Thank you for your comment. An ethics statement has been included in lines 149-152 and under the Institutional Review Board Statement (line 299-302)

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The case report is well investigated, and well written, however, there still some concerns should be addressed.
1. The ethical approval‌ must be provided
2. In table 1, the glucose levels were changed, what happen for binturong during 5 Dec 2019 to 26 Jun 2020, Could you provide more data before 10 Oct 2019?
3. What is the reason for its death? Did diabetes mellitus affect?
4. Why it was diagnosed as Type 2 diabetes mellitus, not T1DM? Please give the evidence.
5. Please add the limitation of this study
6. Figure 2, scale bar is missing.

Author Response

1. The ethical approval‌ must be provided

Authors Reply: Thank you for your comment. An ethics statement has been included in lines 149-152 and under the Institutional Review Board Statement (line 299-302)

2. 
   In table 1, the glucose levels were changed, what happen for binturong during 5 Dec 2019 to 26 Jun 2020, Could you provide more data before 10 Oct 2019?

 

Authors Reply: Thank you for your comment. Blood glucose in this patient, while improved with lower levels measured on 26 Jun 2020, was still above reference ranges. Several reasons may account for this, including normal blood glucose fluctuations throughout the day, corrections to the diet, or the partial recovery of function in beta cells. While diabetic remission is reported in cats, it is unknown if this may occur in binturongs, and this individual technically did not achieve remission.

 

It is unclear what further data is requested by the reviewer prior to initial presentation (10 Oct 2019), but several lines addressing the patient’s husbandry have been added to the manuscript (lines 97-102).

3. What is the reason for its death? Did diabetes mellitus affect?

 

Authors Reply: Thank you for your comment. We clearly report (line 181-182) that the animal was euthanized roughly 4 years following initial diagnosis, based on declining quality of life. The decision was made based on the progression of comorbidities including bilateral cataracts, and spondylosis (line 172-173). The potential role/significance of diabetes mellitus in the progression of these signs (as opposed to other processes such as increased age) is a major point in the discussion section and extensively discussed, from lines 276 onward.

4. Why it was diagnosed as Type 2 diabetes mellitus, not T1DM? Please give the evidence.

Authors Reply: Thank you for your comment. The diagnosis of Type 2 diabetes mellitus was based on the histological detection of amyloid deposition in the pancreatic islets. It is very well documented that this particular presentation is associated only with T2D, as described in other species. T1D is associated with the autoimmune destruction of β-cells, where one commonly sees lymphocytic infiltration and insulitis. Amyloid deposition is not associated with T1D.

4. Please add the limitation of this study

 

Authors Reply: Thank you for your comment. A new paragraph has been added to the discussion section highlighting the limitations of this study, including the single-case nature of the report, as well as the lack of immunohistochemical analysis (lines 241-257). Further down the section, a discussion on confounding conditions and their effect on the interpretation of this case can be found (lines 276 onward).

6. Figure 2, scale bar is missing.

 

Authors Reply: Scale bars have been added to Figure 2.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

Please see file attached 

Comments for author File: Comments.pdf

Author Response

The manuscript presents a well-structured case report documenting the first known occurrence of Type 2 diabetes mellitus (T2D) and pancreatic islet amyloidosis in a binturong (Arctictis binturong). The topic is original, relevant to zoological and veterinary medicine, and contributes significantly to the limited literature on endocrine diseases in non-domestic viverrids. The paper adheres to standard case report structure (Abstract, Introduction, Case Description, Discussion, Conclusion), and references are appropriate and up to date

 

Minor suggestions

 

1. Reformat Tables 1 and 2 for consistency (decimal precision, unit alignment).

 

Authors Reply: Thank you for your comment. The values within both tables have been reviewed and decimal precision/alignment changed for improved consistency and readability.

 

2. Include magnification scale (e.g., 40x, 100x) for histological images.

 

Authors Reply: Thank you for your comment. Scale bars have been added for histological images in Figure 2.

 

3. Please provide the base line bodyweight of the binturong during the disease

progression if possible. Bodyweight was only provided at the time of death.

 

Authors Reply: Body weight for the patient has now been specified for each check performed on the patient (lines 95, 140, 155, 172).

 

4. Add a method section to describe the experiment procedures

 

Authors Reply: We’re afraid we don’t quite understand this suggestion. No experimentation was performed, as this case report details the diagnosis and management of a patient seen in the hospital. The diagnostic process included the performance of hematology, biochemistry, ultrasonography and urinalysis, all of which are described in detail in the Materials and Methods/Case Description section. Further information regarding blood draw and sedation protocols have been added between lines 106-112.

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

The author addressed all concerns