Fish Feeds in Aquaponics and Beyond: A Novel Concept to Evaluate Protein Sources in Diets for Circular Multitrophic Food Production Systems

Round 1

Reviewer 1 Report

Dear authors,

If it were for the style of writing I would have to recommend: reject the paper because the article is too wordy, often confusing and style is more prozaic than scientific.   

However, I put myself in my teacher modus and commented exhaustively on sentences, sections and chapters. As I put already a lot of time in reviewing this manuscript, I just request you to read my comments in attached pdf. While revising, please consider that scientific papers should focus on the topic (thus replace text relating the reader to CUBES to one reference and use relevant scientific references for others.

Moreover I advise all authors to and follow a workshop on Scientific writing or study the book of e.g.  Birgitta Malmfors, Philip C. Garnsworthy, Michael Grossman  (Writing and Presenting Scientific Papers. Front Cover). For the content of Introduction I attach a short overview:

 

The content of Introduction in four paragraphs with nine points in total:

Context: sets the importance, makes generalization(s) and reviews previous research.

Need/Niche of your study: indicates a gap to add to what is known, or presents positive justifications by using literature.

Task/scope of your study: presents research questions or hypotheses, and gives clarifications or limitations.

Object of the paper: summarises the approach, and outlines the structure of the paper.

 

Success with the revision.

Comments for author File: Comments.pdf

Author Response

Dear Reviewer,

 

Thank you for your effort in reviewing our manuscript and for making extensive suggestions for improvements.

We have thoroughly gone through all your comments and tried to implement the suggestions to the best of our understanding with specific focus on being more concise and precise.

Please find our specific replies to your comments in the attached PDF and their implementation in the revised manuscript.

We are looking forward to your response.

Author Response File: Author Response.pdf

Reviewer 2 Report

This manuscript provides valuable information for utilization of alternative protein and aquaponics.  
However, in my opinion, discussion is too long, and much literature was cited.
If possible, it is better that author makes discussion focused on important matter that author thinks particular important, and references are reduced .

FCR and PER should be calculated including BW of dead fish, since survival rate was different between treatment.   

Author Response

Dear Reviewer,

Thank you for taking the time to review our manuscript.

We have generally shortened the manuscript and especially the discussion with focus on being more concise as you have suggested. Also, the conclusion has been revised.

Please find all changes in the updated manuscript.

With regard to FCR and PER, the calculations were done to adjust for the distorting effect of differing mortality between treatments in order to make these measures comparable between treatments and to communicate more realistic FCR/PER values that are not artificially suppressed by mortality.  Total feed fed per individual (as in the FCR calc.) and CP fed per individual (as in the PER calc.) already exclude the effect of mortality, i.e.:

Each day of the trial the total number of individuals per tank (and thus also a reduced total number of individuals per tank due to mortality) as well as the amount of feed administered per tank on each specific day were recorded. Accordingly, the average amount of feed each remaining individual at the end of the trial has received over the entire trial was calculated. This ‘mortality adjusted’ total feed per individual (remaining at the end of the trial) was used to calculate FCR/PER.

FCR = total feed fed per individual (g as fed or DM) / [final mean body weight (g) - initial mean body weight (g)]

PER – protein efficiency ratio = (mean individual body weight gain (g) / CP fed per individual (g))

Accordingly, an explanatory sentence was added in section 2.3.2 - Fish performance indices (line 227-230).

We are looking forward to your response with regard to the revised manuscript.

Round 2

Reviewer 1 Report

Dear authors

Your article has improved greatly. Still the text has some issues (wordy, long or confusing sentences) and the last section of the Discussion is long and therefor confusing. Moreover, I proposed a title that's in line with the paper's content; I see no reason to refer to this complicated system name.  To clarify the last part of the Discussion I propose to split this in three sections: Feces and aquaponics, Feces for insect feed, Integrated tri-trophic systems.

NB: the first revised version I received was the non-cleared version; I was halfway my review when I received the cleared version. Reading was not always easy, but as I was already halfway, I continued in this version. Sorry, that this happened, I realize that also for the author team identifying all my comments and suggestions will not be easy.

Success with the last revisions. 

Comments for author File: Comments.pdf

Author Response

Dear Reviewer,

 

Thank you again for your detailed suggestions to improve our manuscript which we tried to implement as thoroughly as possible.

Please find attached a PDF with our specific replies to your comments and a Word document with the accordingly revised version of the manuscript.

We are looking forward to your response.

Author Response File: Author Response.pdf