Histological Evaluation of Purple Sea Urchin (Paracentrotus lividus) Gonads: Influence of Temperature, Photoperiod Regimes, and Diets

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

João et al. explored the impact of temperature, photoperiod, and diet on gonadal development. Their results found that by feeding with suitable inert formulated feeds and manipulating environmental conditions it is possible to create conditions that allow to get spawning all year round and marketable gonads to be obtained at different times of the year, which helps to increase the sales value of sea urchins and optimize commercial production. My sense of this paper is that the science is generally defensible and feasible, but I feel it could benefit from some additional work on the figures and method description.

 

 

1. At line 38, 117, 190, 337, 357, 372, 381, 414, 448, 468 require first line indentation.

 

2. Materials and Methods. – Table 1 suggests using a three line table for production.

 

3. The significance p should be italicized, please unify the entire text.

 

4. Results. – Figure 2 is not very clear. It is recommended to improve the clarity of Figure 2, and the vertical axis should be Gonadological index (GI) instead of IG.

 

5. At line 235, should be modified to “3.2. Gonad development”.

 

6. References. – The literature citations are not in any one format regarding whether key words of journal titles are capitalized or not. They should be consistent and in conformance with journal citation stylistics.

Comments on the Quality of English Language

Minor editing of English language required.

Author Response

Dear reviewer,
Thank you in advance for your attention. I've taken all your comments and suggestions and made the appropriate changes. I think that now, after the constructive input of the reviewers, the article is much better. Below are the answers to your comments. Attached is the manuscript after changes.

 

1. At line 38, 117, 190, 337, 357, 372, 381, 414, 448, 468 require first line indentation.

The formatting has been corrected 

2. Materials and Methods. – Table 1 suggests using a three line table for production.

I've changed the table as suggested

3. The significance pshould be italicized, please unify the entire text.

Right. I've changed it 

4. Results. – Figure 2 is not very clear. It is recommended to improve the clarity of Figure 2, and the vertical axis should be Gonadological index (GI) instead of IG.

Sure .I've changed the table as suggested

5. At line 235, should be modified to “3.2. Gonad development”.

Corrected

6. References. – The literature citations are not in any one format regarding whether key words of journal titles are capitalized or not. They should be consistent and in conformance with journal

You're right. I found the flaws and corrected them

 

 

Author Response File: Author Response.docx

Reviewer 2 Report

Comments and Suggestions for Authors

Feeding, temperature and photoperiod manipulation are very important influencing factors on aquatic animals. The experimental design, research results and conclusions of this paper belong to the conventional content, and there are few innovative points. Most of the references are from before 2020, does it mean that the research content is not innovative enough?

The histology sections are not clear enough and needs to be updated.

Author Response

Dear reviewer, thank you for your comments. 
The histology images have been improved and reintroduced. In addition to improving the images, changes and corrections have been made to the information related to the images. As far as the references are concerned, I believe there may be other studies, some of them more recent, but I couldn't find them during my literature search. During the 5 days given by the editors, I was able to respond to a large number of comments and requests for changes from the 3 reviewers, in a particularly busy week, and it was not possible to carry out a new bibliographic search. I am sorry. Thank you for your attention and review. The corrected manuscript is attached. Best regards

Author Response File: Author Response.docx

Reviewer 3 Report

Comments and Suggestions for Authors

The feeding, temperature and photoperiod is assessed in the development of sea urchin Paracentrotus lividus gonads. Overall, the manuscript shows good writing and organization. The content of this study is rich and substantial, which is helpful to further understanding how to obtain the good quality of the sea urchin gonads throughout the year in aquaculture. Therefore, in my opinion this manuscript is publishable with minor revision as suggested in Comments for the authors.

Title: A suggestion is to exclude the 1^st “and” and “manipulation”, thus the title would be: Influence of Feeding, Temperature and Photoperiod on Purple Sea Urchin….”

Abstract:

Line 21 – Please rephrase the sentence it is not stated clear. Maybe: GSI and HA were used to assess gonad development. Also, please note that it is “gonad development”, as you stated in the Title of the paper, but missed in a lot of other places throughout the paper. Please correct every time this is used in the paper, I will note further.

Line 29 – “…. Enhances the commercial value … of sea urchins – please add because it is missing in the context.

Line 29-30 – please rephrase the sentence it is not clear, especially the ending “yield-maximizing production strategies…” to “maximal production of gonads throughout the year.

Keywords:

A kind suggestion would be to replace echinoderms with sea urchins, since actually this is the word you used the most throughout the paper, not echinoderms. Another suggestion would be to add gonadosomatic index as a keyword.

Introduction:

Line 38 – before “In some…” there might be an extra “space”, please check and delete if so.

Line 50 – would suggest to state “from fishing wild populations”, without “in”.

Line 54 – a suggestion is to rephrase “yearly” with “throughout the year”

Line 56-57 – Sentence does not sound good, please add “sea urchin” somewhere…

Line 59 – should state “gonad development” and again please add gonad development of sea urchin.

Line 69 – A suggestion is to rephrase “To do this” with “For this reason…” or “Thus,”

Mat&Meth:

Line 75 – A “space tab” is somewhere present in other paragraph beginnings it is not – please unify throughout the paper.

Line 93 – before “The tanks…” there might be an extra “space”, please check and delete if so.

Line 100 - 20± 0.5 – add or delete a space, and unify throughout the paper. Because later at all places you write the st. dev. in brackets (e.g. Line 130 and Table 1). My suggestion is not to put brackets but to write 20 ± 0.5 or 20±0.5 – whatever you decide please unify throughout the paper.

Line 103 – “… settlement began approximately 20 and 30 days…”

Line 108 – put nb. 9 in superscript, so as to have 6x10⁹ cells

Line 110 – add commas before and after “previously washed with fresh water”, and the verb here should be “started”.

Line 114 – Add space between “22°C”

Line 118 – A suggestion for the naming is to lose the commas, because it is difficult to read (please see Line 126), and write just a space between as you did in Line 192 also Line 213: so to be NoM U – what it stands for, NoM If – what it stands for, and so on… Also, please note that the repetition of the meaning is not necessary further once you named the special conditions, thus I would suggest to delete it in the Line 191-193.

Line 121 – The rackets stating (M, It) – is not needed at this point since it is a repetition of “M, If –“

Line 124 – Add a space between 3mm.

Line 129 – It is not clear what does “F1” stands for at this point.

Line 130 – I would suggest to lose the brackets.

Line 144 – should state “(Table 1)”

Line 160 – the ending of the Line ends with a dot, and the new Line 161 starts with a small case?

Line 162-163 – If possible would be ok to have same number of decimals for the grams at both spots.

Line 169 – add a space between “n = 25…”

Line 177 – add a space between “48 h”

Line 181 – delete an extra unnecessary opening bracket

Line 183 – could be an extra space before the beginning of the new sentence

Line 185 – same as Line 183

Line 187 – add citation number in brackets []

Line 191-194 – naming again the conditions of the experiment at this point is not necessary, a suggestion is to exclude

Results

Line 206-234 I would kindly suggest to use the abbreviation “GSI” in this paragraph.

Line 209 – “… both sexes fed WITH inert food” – please add “WITH” before naming the food applied in the experiment – and please do so at all places where the same is mentioned, I will try to mention them all.

Line 215 add “fed WITH”

Line 220 delete “the”, it is not necessary

Line 226 Figure 2. (a dot, not “:”) the p value regarding (p<0.05) – to the best of my knowledge it is written in small case and in italic. If you agree, please check throughout the paper.

Line 232, 233, 234 add “fed WITH”

Line 238 Please add a dot in “Figures 3. and 4. describe…”

Figure 3. and 4. Kindly note that it is unusual for sea urchins to state that they have “testis” or “ovaries”, please rephrase in “male gonads” – same as you did in the naming of the Fig. 5. And 6. Also, if possible it would be nice to have the naming of the different stages on the photos. Line 246 – Please rephrase the sentence “You can have relict spermatozoa.”

Figure 4. Line 254. I am missing the NF on the photos? Should it be NP? Line 257 – add space between 50 µm and a dot after that. Line 262 - PO is missing on the photos.

Line 272 – delete an extra dot and name Figure 5. and 6.

Line 273 – Figure 5. à add a dot

Line 274-277 Again the naming of each procedure is not needed.

Line 278 – looks like an extra space before the start of the new sentence

Line 283, 289, 295, 298, 300 (on 2 places), 312, 314, 315, 319, 32, 326, 388, 390, 398, 399, 403, 411, 464- add “fed WITH”

Line 291 – rephrase to “all observed individuals”

Line 294 and 297 Please write “70%” not “per cent” in words.

Figure 5. add citation reference at the end of the Figure description.

Line 310 delete the interlink between “sea-urchin”

Line 312 correct to capital letter: (Figure 6).

Line 314 delete extra space between 63%

Line 319 should write “sea urchin” without the link

Line 334 you state here “unmanipulated”, earlier in the paper you write #non-manipulated”, might be better

Discussion

Line 337 is necessary

Line 348-349 This sentence is already stated very similar or the same in the Intro section, please rephrase to state clearly that you are referring to the sea urchin spawning cycle.

Line 358 please add “reproductive cycle OF THE SEA URCHIN…”

Line 362 A suggestion is to replace the verb “were aggregated” with “were merged” or “were merged together”

Line 363 Please rephrase the sentence so as not to repeat the verb “create”/recreate

Line 364 delete the space in “non-manipulated”

Line 371 delete an extra “s”

Line 375 Here you use GI abbreviation for the gonadosomatic index, whereas earlier you abbreviated as GSI – might be better. Also, once you mention the abbreviation, please consider also using it in the paragraph. E.g. in Lines 386, 378, 389, 394

Line 378 should write “gonad development cycle”, you write it well in Line 381

Line 380 A suggestion here is to use the verb “signalling”

Line 382-384 The beginning and the end of the sentence sound non understandable, please rephrase or split into two sentences to make the point.

Line 394 delete an extra space before the sentence “It is…”

Line 397 Reference number should be added in [], the year is not necessary. Please correct the same also in Line 400, 417, 436, 440

Line 401 What does “DM” here stands for? Also, the -1 should be written as superscript.

Line 413 should write Gonad maturity

Line 434 the verb here should be “provided”

Line 456 A suggestion is to delete “even”.

Line 466 please add “Iberian population OF SEA URCHINS.”

References

Some years are not written in bold, please check and correct.

Figures

Please note that the naming of the Figure should state “Figure 1. Description of the figure…” the same for the Table 1. and should also always end with a dot (.) Check in all Figures and correct accordingly.

Table 1. I would suggest again to lose the brackets.

Author Response

Dear proofreader, thank you in advance for all your attention and patience in proofreading our work. I consider all your comments and suggestions to be very correct and likely to improve the quality of the manuscript.

Below is the answer to all your comments. 

Attached is the corrected manuscript

 

Best regards

 

Title: A suggestion is to exclude the 1^st “and” and “manipulation”, thus the title would be: Influence of Feeding, Temperature and Photoperiod on Purple Sea Urchin….”

I had written it that way because photoperiod and temperature were associated in the manipulation. But I agree that it looks better as you said. 

Abstract:

Line 21 – Please rephrase the sentence it is not stated clear. Maybe: GSI and HA were used to assess gonad development. Also, please note that it is “gonad development”, as you stated in the Title of the paper, but missed in a lot of other places throughout the paper. Please correct every time this is used in the paper, I will note further.

The change has been made as suggested

Line 29 – “…. Enhances the commercial value … of sea urchins – please add because it is missing in the context.

Due to the word limit, I made a few cuts. But I've now made the suggested changes.

Line 29-30 – please rephrase the sentence it is not clear, especially the ending “yield-maximizing production strategies…” to “maximal production of gonads throughout the year.

The change has been made as suggested

Keywords:

A kind suggestion would be to replace echinoderms with sea urchins, since actually this is the word you used the most throughout the paper, not echinoderms. Another suggestion would be to add gonadosomatic index as a keyword.

The change has been made as suggested

Introduction:

Line 38 – before “In some…” there might be an extra “space”, please check and delete if so.

It's true. Corrected.

Line 50 – would suggest to state “from fishing wild populations”, without “in”.

Corrected.

Line 54 – a suggestion is to rephrase “yearly” with “throughout the year”

Corrected.

Line 56-57 – Sentence does not sound good, please add “sea urchin” somewhere…

The change has been made as suggested

Line 59 – should state “gonad development” and again please add gonad development of sea urchin.

Corrected.

 

Line 69 – A suggestion is to rephrase “To do this” with “For this reason…” or “Thus,”

The change has been made as suggested

Mat&Meth:

Line 75 – A “space tab” is somewhere present in other paragraph beginnings it is not – please unify throughout the paper.

I have corrected the formatting

Line 93 – before “The tanks…” there might be an extra “space”, please check and delete if so.

Fixed.

Line 100 - 20± 0.5 – add or delete a space, and unify throughout the paper. Because later at all places you write the st. dev. in brackets (e.g. Line 130 and Table 1). My suggestion is not to put brackets but to write 20 ± 0.5 or 20±0.5 – whatever you decide please unify throughout the paper.

20±0.5

Line 103 – “… settlement began approximately 20 and 30 days…”

Amended

Line 108 – put nb. 9 in superscript, so as to have 6x10⁹ cells

Fixed

Line 110 – add commas before and after “previously washed with fresh water”, and the verb here should be “started”.

 Amended

Line 114 – Add space between “22°C”

I didn't realize where you wanted to put the space. 22ºC sounds good to me.

Line 118 – A suggestion for the naming is to lose the commas, because it is difficult to read (please see Line 126), and write just a space between as you did in Line 192 also Line 213: so to be NoM U – what it stands for, NoM If – what it stands for, and so on… Also, please note that the repetition of the meaning is not necessary further once you named the special conditions, thus I would suggest to delete it in the Line 191-193.

You're definitely right. It has been corrected.

Line 121 – The rackets stating (M, It) – is not needed at this point since it is a repetition of “M, If –“

Amended

Line 124 – Add a space between 3mm.

Amended

Line 129 – It is not clear what does “F1” stands for at this point.

F1 generation. It was added

Line 130 – I would suggest to lose the brackets.

Fixed.

Line 144 – should state “(Table 1)”

Amended

Line 160 – the ending of the Line ends with a dot, and the new Line 161 starts with a small case?

Amended

Line 162-163 – If possible would be ok to have same number of decimals for the grams at both spots.

Right. Amended

Line 169 – add a space between “n = 25…”

Corrected.

Line 177 – add a space between “48 h”

Corrected.

Line 181 – delete an extra unnecessary opening bracket

Corrected.

Line 183 – could be an extra space before the beginning of the new sentence

Corrected.

Line 185 – same as Line 183

Corrected.

Line 187 – add citation number in brackets []

I've added the number in brackets, but I've kept the author's name because I think it's part of the sentence.

Line 191-194 – naming again the conditions of the experiment at this point is not necessary, a suggestion is to exclude

Sure. Excluded.

Results

Line 206-234 I would kindly suggest to use the abbreviation “GSI” in this paragraph.

The change has been made as suggested

Line 209 – “… both sexes fed WITH inert food” – please add “WITH” before naming the food applied in the experiment – and please do so at all places where the same is mentioned, I will try to mention them all.

The change has been made as suggested

Line 215 add “fed WITH”

Corrected.

Line 220 delete “the”, it is not necessary

Corrected.

Line 226 Figure 2. (a dot, not “:”) the p value regarding (p<0.05) – to the best of my knowledge it is written in small case and in italic. If you agree, please check throughout the paper.

You're definitely right. It has been corrected.

Line 232, 233, 234 add “fed WITH”

Corrected.

Line 238 Please add a dot in “Figures 3. and 4. describe…”

Corrected.

Figure 3. and 4. Kindly note that it is unusual for sea urchins to state that they have “testis” or “ovaries”, please rephrase in “male gonads” – same as you did in the naming of the Fig. 5. And 6. Also, if possible it would be nice to have the naming of the different stages on the photos. Line 246 – Please rephrase the sentence “You can have relict spermatozoa.”

Figure 4. Line 254. I am missing the NF on the photos? Should it be NP? Line 257 – add space between 50 µm and a dot after that. Line 262 - PO is missing on the photos.

Line 272 – delete an extra dot and name Figure 5. and 6.

Corrected.

Line 273 – Figure 5. à add a dot

Corrected.

Line 274-277 Again the naming of each procedure is not needed.

Corrected

Line 278 – looks like an extra space before the start of the new sentence

Corrected

Line 283, 289, 295, 298, 300 (on 2 places), 312, 314, 315, 319, 32, 326, 388, 390, 398, 399, 403, 411, 464- add “fed WITH”

Corrections have been made

Line 291 – rephrase to “all observed individuals”

Corrected

Line 294 and 297 Please write “70%” not “per cent” in words.

Corrected

Figure 5. add citation reference at the end of the Figure description.

Added

Line 310 delete the interlink between “sea-urchin”

Deleted

Line 312 correct to capital letter: (Figure 6).

Corrected

Line 314 delete extra space between 63%

Corrected

Line 319 should write “sea urchin” without the link

Corrected

Line 334 you state here “unmanipulated”, earlier in the paper you write #non-manipulated”, might be better

Corrected

Discussion

Line 337 is necessary

Corrected

Line 348-349 This sentence is already stated very similar or the same in the Intro section, please rephrase to state clearly that you are referring to the sea urchin spawning cycle.

Changed

Line 358 please add “reproductive cycle OF THE SEA URCHIN…”

Added

Line 362 A suggestion is to replace the verb “were aggregated” with “were merged” or “were merged together”

were merged together

Line 363 Please rephrase the sentence so as not to repeat the verb “create”/recreate

The phrase has been changed to “Therefore, two independent cultivation systems were developed to simulate the environmental conditions of two different seasonal periods”

Line 364 delete the space in “non-manipulated”

Changed

Line 371 delete an extra “s”

Changed

Line 375 Here you use GI abbreviation for the gonadosomatic index, whereas earlier you abbreviated as GSI – might be better. Also, once you mention the abbreviation, please consider also using it in the paragraph. E.g. in Lines 386, 378, 389, 394

I've made the change. I just kept the full name, without abbreviation at the beginning of the chapter.

Line 378 should write “gonad development cycle”, you write it well in Line 381

I've standardized the entire document to the correct form

Line 380 A suggestion here is to use the verb “signalling”

I have corrected the verb as indicated

Line 382-384 The beginning and the end of the sentence sound non understandable, please rephrase or split into two sentences to make the point.

You're right, the sentence was poorly put together. It has been corrected.  (During the progression of gametogenesis, the number of germ cells increases, and nutrient reserves accumulate in the somatic cells, specifically the nutritive phagocytes, at the onset of this process)

Line 394 delete an extra space before the sentence “It is…”

Corrected

Line 397 Reference number should be added in [], the year is not necessary. Please correct the same also in Line 400, 417, 436, 440

OK, that correction has been made for all the references that were incorrectly inserted. 

Line 401 What does “DM” here stands for? Also, the -1 should be written as superscript.

Dry matter. Corrections have been made

Line 413 should write Gonad maturity

Corrected

 

Line 434 the verb here should be “provided”

Corrected

Line 456 A suggestion is to delete “even”.

Done

Line 466 please add “Iberian population OF SEA URCHINS.”

Added

References

Some years are not written in bold, please check and correct.

True. Corrected

Figures

Please note that the naming of the Figure should state “Figure 1. Description of the figure…” the same for the Table 1. and should also always end with a dot (.) Check in all Figures and correct accordingly.

Table 1. I would suggest again to lose the brackets.

Changes have been made

 

 

Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

Acceptable in present form.