Examination of Nesting Behavior of Laying Hens of Different Genotypes Housed in Indoor Alternative Pens Using a Video System
Round 1
Reviewer 1 Report
The aim of this research was to :
1. examine the nest selection preference of laying hens of different genotypes
2. the proportion of eggs laid in the litter, nests in different levels,
3. number and duration of nest visits
The experimental design and the items being observed and compared were suitable. However, the biggest flaw of this research is that the three genotypes which were selected were not appropriate. The main reason to conduct this experiment was due to the information needed for moving to alternative rearing system from cage system to non-cage system with regard to animal welfare aspect. This is indeed very important, but the type of hens selected for the experiment should all be commercial line. Comparing the three types selected in this experiment cannot meet the information needed unless if the purpose is for the breeding program of commercial lines. Even so, different pure-lines should be compared, but not just one maternal and one paternal line. Base on the major flaw of the target selection, this manuscript is not suggested for publication. There are also some major errors as following:
1. line 182, “line Maternal genotype” is incorrect, the correct wording should be “line Paternal genotype”
2. line 202-205: The comparison of the result between this experiment and Villanueva et al was not appropriate. Their results were comparisons for the brown vs white, but not maternal genotype vs paternal genotupe.
3. line 414: “Peternal” should be “Paternal”
4. line 420: “Giersberg et al. (9) like us”； this sentence is wrong
Author Response
Response to Reviewer 1 Comments
The experimental design and the items being observed and compared were suitable. However, the biggest flaw of this research is that the three genotypes which were selected were not appropriate. The main reason to conduct this experiment was due to the information needed for moving to alternative rearing system from cage system to non-cage system with regard to animal welfare aspect. This is indeed very important, but the type of hens selected for the experiment should all be commercial line. Comparing the three types selected in this experiment cannot meet the information needed unless if the purpose is for the breeding program of commercial lines. Even so, different pure-lines should be compared, but not just one maternal and one paternal line. Base on the major flaw of the target selection, this manuscript is not suggested for publication.
Response:
First of all, we would like to thank you for taking on the task of correcting the manuscript. We are glad that you found the experimantal design suitable.
We fully understand and accept your logic regarding the choice of genotypes.
At the same time, the selection of genotypes was supported by well-planned work both professionally and scientifically.
Furthermore, it was not only our research group's, but also the company's desire to examine these genotypes. In addition, the other reviewers also found the genotype selection appropriate.
In the literature, we can find many types of genotype comparisons (almost everything has been compared: hybrids, varieties, lines, species, wild species, etc.), which science has accepted and enriched our knowledge.
Prohibiting the comparison of some genotypes or the publication of the results is contrary to the freedom and ethics of science.
We kindly ask you to accept our reply in this regard.
Point 1: line 182, “line Maternal genotype” is incorrect, the correct wording should be “line Paternal genotype”
Response 1: You are absolutely right. I corrected.
Point 2: line 202-205: The comparison of the result between this experiment and Villanueva et al was not appropriate. Their results were comparisons for the brown vs white, but not maternal genotype vs paternal genotupe.
Response 2: You are right that this comparison is not the most appropriate, so I deleted it.
Point 3: line 414: “Peternal” should be “Paternal”
Response 3: You are right, so I corrected it.
Point 4: line 420: “Giersberg et al. (9) like us”； this sentence is wrong
Response: I agree with you. I corrected
In the revised manuscript, you can view comments, replies to them, and any changes to the manuscript.
You are Reviewer 1, I have marked your comments in blue.
Please see the attachment
Author Response File: 
Author Response.docx
Reviewer 2 Report
I found the manuscript (MS) very exciting and I congragulate the authors for their work. Because, eggs laid on floor has always been a problem for breeder farms. Therefore, during the selection of maternal lines nest usage is of importance for breeders as it was also shown in this study. However, promotion for egg production in non-cage systems in EU and many other parts of the world, it also become a problem for table egg production together with gregarious nesting, smothering etc. Data from this study may supply relevant information to the area and may improve our understanding to solve the problem.
However, the manuscript has several shortcomings that makes controversial the acceptability of it as it is. My major concerns are summarized below:
1. Description of study environment and statistical methods used in the MS is not clear. This make it difficult to interpret results correctly.
2. There are problems in scientific writing style in English language and terminology in poultry science. Scientific writing needs to be unbiased, simple and clear enough to help readers for easy understanding.
Detailed comments are as following:
Title is attractive but “alternative” term is not clearly described within the text.
Abstract: In general, careful editing is needed for fluency and clarity. And, conclusion sentence should be rephrased for a better presentation of the findings of the study i.e differences among genotypes in nest usage thus litter eggs.
Intro: Writing style needs to be edited for a clear and easy readable scientific language. In general, there are very complicated paragraphs with long sentences connected to each other which makes difficult to understand the main point. Such as Line 38-43. Lines: 49-52. Line 86-91.
This comment is applicable to mainly introduction but also to the whole MS.
Line 49-50 : I think there is a misinterpretation of literature. Traditional/conventional cages do not contain nest. But, enriched ones do as they were developed to improve hen’s welfare by offering them to perform their natural behaviors such as nesting, scratching, perching, wing opening etc. Please clarify.
Line 70-71: instead of “keeping” “housing” would be a better term.
Line 92-05: This part is out of this paper’s scope. Furthermore, it advocates that selection for less aggressive birds resultes in more floor eggs without giving any scientific reference. This might be a hypothesis and needs to be proven with scientific evidences. So, if it is not based on scientific evidences it can not be accepted. Should be removed. But the if the genotypes used in this study had a selection background for lowering aggression , this may be your study hypothesis. In that case, the study aim should be changed. Please clarify.
Line 107: What is “alternative husbandry” ? It should be clearly described in M&M section as because your title also include “alternative pens”. To common understanding is that “alternative” refers usually non-cage housing systems such as aviary. Or any non-cage system has access to outdoor.
M&M: Experimental pens should be clearly described to clarify “alternative “term. Experimental pens had an area of 5.5 square meter with 53 hens, 1/3 littered , 2/3 plastic grid/ slatted area . Would it be any other terms such as “barn with 1/3 littered are “ Non-cage indoor housing with partly slatted floor “ etc. I would ask the authors to find a better description, if they can. Was there perching system in the pens? Because if we talk about a welfare friendly alternative housing to conventional cage system, perches are necessary. And, although there are some photos of nest sites it would be great if it is possible to give a schematic figure of the pen.
Line 141: Bottom nests were not used well. Would it be possible that they find it difficult to reach? So, if any structure such as ramps would be helpful? Just for discussun!
Statistics: Statistic methods used in the study are not clear enough. “Likelyhood Ratio test” is very common title. Could you give details of methods and statistical models? Please add relevant information showing how you proceed data during preliminary analyses and how you decide to use entire method. Did nest visits and laying sites (litter or nest eggs) data show normal distribution? Non parametric options? Did you check possibility for to analyze such as nest usage data (litter and nest eggs proportion) by a simple two way ANOVA etc. Please supply relevant information to clarify.
Results and Discussion/ Conclusion: Most of the conclusion part a repetition of results and discussion section. It is expected that conclusion should be mainly one or two paragraphs which summarize main conclusions from the study and give the future directions. It should be rewritten. Some of the discussions in the conclusion part would be moved to results and discussion section where they are suitable.
Line 185-196: Please incorporate two paragraphs into one.
Line 190-196: If you point out that difference was not significant, last sentence would be a misinterpretation of data. Because differences is not significant.
Line 197-200: I agree with the authors. But what is your the comment for solution? I think that is why selection of pure lines needs to be done in the similar conditions (floor) using with trap nests. As, it was possible in the very early times of poultry breeding. Yes, it will increase the costs. Please discuss it.
Line 201-205: So, genetics matters for the litter eggs or nest usage of hens.
Line 206-208: Here it is necessary to add what practical steps are. And, I think this is the main discussion. Beside genetic selection, stocking density, nests management, nest type, nest material, nest floor (here plastic/artificial grass ), location of nest rows in the house, light intensity at the level of nest etc. all deserve to be referred.
Line 300-313: Most of the information should be moved to M&M section. But I would say that repeated observations definitely would be more reliable and would increase the impact of the study.
Table 3: Table is quite confusing and difficult to read. Beside, M&M section statistics part did not tell us the statistical model used. And the title: I would suggest that no need to explain” egg nest “ or “laying nest” please correct them all in the other titles as “nest”.
Line 346-347: Please explain how you do relate this information with your findings. Otherwise it is unnecessary.
Line 382-386: It could be interesting to check correlations between the number of visits or duration and egg numbers laid in nests.
Line 394-397: Repetition of M&M section. Please remove.
Line 407: “standard deviation” They were not given on the tables. Should be added.
Line 420-423: They used a single line of colony nest in aviary system and compared at the middle one with the one at the corner. In this study, standard individual nests were used. Please discuss your data regarding their findings. What did they find? And how related to your data.
Conclusions
Conclusion part a repetition of results and discussion section. Please shorten it to one or two paragraph and give the main conclusion only.
Line 445: “I measured “ Not suitable for scientific writing. Please rephrase.
Line 448-456: Mostly Repetition of the results. Please remove.
458-460: Repetition of the results. Please remove.
461-472: Should be moved to discussion section.
473-477: Should be moved to discussion where it is suitable.
484: Based on my test; again not suitable for writing. Please rephrase.
Line 490-492: I would say, I found this conclusion far beyond available data which rely only the parental lines and hybrid of a breeder company. I appreciate the study which is highly valuable to show that layers coming from conventional selection strategies may not have good nesting behavior. And, this study does this. However, we need solutions not to frighten people.
Line 493-494: “chosen” suggest to replaced with “selected” and “keeping” to “ housing conditions”.
Author Response
Response to Reviewer 2 Comments
I found the manuscript (MS) very exciting and I congragulate the authors for their work. Because, eggs laid on floor has always been a problem for breeder farms. Therefore, during the selection of maternal lines nest usage is of importance for breeders as it was also shown in this study. However, promotion for egg production in non-cage systems in EU and many other parts of the world, it also become a problem for table egg production together with gregarious nesting, smothering etc. Data from this study may supply relevant information to the area and may improve our understanding to solve the problem.
Response: I am glad and thank you that you also found our work exciting and important.
Point: Description of study environment and statistical methods used in the MS is not clear. This make it difficult to interpret results correctly.
Response: We tried to include as many pictures and figures as possible to clearly illustrate the environment of the research. This is how we usually describe the statistical evaluation and it is accepted in other manuscripts as well. We hope you will accept it.
Point: There are problems in scientific writing style in English language and terminology in poultry science. Scientific writing needs to be unbiased, simple and clear enough to help readers for easy understanding.
Response: We agree that it is worth improving scientific writing in English. That's why we corrected the things you requested where we could. in many places, we have simplified, corrected and deleted some parts. You can see this in the manuscript.
Point: Title is attractive but “alternative” term is not clearly described within the text.
Response: We have tried to do a lot to specify the parameters of this alternative system as clearly as possible. We have described the parameters. In compliance with your request, we have included a new image that fully depicts the alternative pen with all its equipment.
Point: Intro: Writing style needs to be edited for a clear and easy readable scientific language. In general, there are very complicated paragraphs with long sentences connected to each other which makes difficult to understand the main point. Such as Line 38-43. Lines: 49-52. Line 86-91.
Response: I agree, so I changed all the marked sentences.
Point: Line 49-50 : I think there is a misinterpretation of literature. Traditional/conventional cages do not contain nest. But, enriched ones do as they were developed to improve hen’s welfare by offering them to perform their natural behaviors such as nesting, scratching, perching, wing opening etc. Please clarify.
Response: You are absolutely right, I know it too. I worded it wrong. I corrected the sentence.
Point: Line 70-71: instead of “keeping” “housing” would be a better term.
Response: I agree, I modified it.
Point: Line 107: What is “alternative husbandry” ? It should be clearly described in M&M section as because your title also include “alternative pens”. To common understanding is that “alternative” refers usually non-cage housing systems such as aviary. Or any non-cage system has access to outdoor.
M&M: Experimental pens should be clearly described to clarify “alternative “term. Experimental pens had an area of 5.5 square meter with 53 hens, 1/3 littered , 2/3 plastic grid/ slatted area . Would it be any other terms such as “barn with 1/3 littered are “ Non-cage indoor housing with partly slatted floor “ etc. I would ask the authors to find a better description, if they can. Was there perching system in the pens? Because if we talk about a welfare friendly alternative housing to conventional cage system, perches are necessary. And, although there are some photos of nest sites it would be great if it is possible to give a schematic figure of the pen.
Response: We have tried to do a lot to specify the parameters of this alternative system as clearly as possible. We have described the parameters. In compliance with your request, we have included a new image that fully depicts the alternative pen with all its equipment.
Point: Line 141: Bottom nests were not used well. Would it be possible that they find it difficult to reach? So, if any structure such as ramps would be helpful? Just for discussun!
Response: It's a very good question, and I completely agree with its clarification. The height of the placement of the nests and the pop-up slats made it easier and unhindered for the laying hens to get into the nest.
Point: Results and Discussion/ Conclusion: Most of the conclusion part a repetition of results and discussion section. It is expected that conclusion should be mainly one or two paragraphs which summarize main conclusions from the study and give the future directions. It should be rewritten. Some of the discussions in the conclusion part would be moved to results and discussion section where they are suitable.
Response: I agree that the conclusions section should be reformatted. Accordingly, I modified, simplified, deleted and moved some parts, which you can follow in the manuscript.
Point: Line 185-196: Please incorporate two paragraphs into one.
Response: I agree, I did it.
Point: Line 190-196: If you point out that difference was not significant, last sentence would be a misinterpretation of data. Because differences is not significant.
Response: I agree, I deleted the sentence.
Point: Line 197-200: I agree with the authors. But what is your the comment for solution? I think that is why selection of pure lines needs to be done in the similar conditions (floor) using with trap nests. As, it was possible in the very early times of poultry breeding. Yes, it will increase the costs. Please discuss it.
Response: I Agree with your statement. That is why I completed the paragraph.
Point: Line 206-208: Here it is necessary to add what practical steps are. And, I think this is the main discussion. Beside genetic selection, stocking density, nests management, nest type, nest material, nest floor (here plastic/artificial grass ), location of nest rows in the house, light intensity at the level of nest etc. all deserve to be referred.
Response: I Agree with your statement. That is why I completed the sentence.
Point: Line 300-313: Most of the information should be moved to M&M section. But I would say that repeated observations definitely would be more reliable and would increase the impact of the study.
Response: I agree with every statement. So I moved this section to the M&M chapter.
Point: Table 3: Table is quite confusing and difficult to read. Beside, M&M section statistics part did not tell us the statistical model used. And the title: I would suggest that no need to explain” egg nest “ or “laying nest” please correct them all in the other titles as “nest”.
Response: You are right that the table is not the simplest, but at the same time I tried to present the location of each nest in the table as they are in reality to help the reader in their interpretation (Figure 2).
I agree with your comment to correct the terms laying nest to nest. I did it.
Point: Line 346-347: Please explain how you do relate this information with your findings. Otherwise it is unnecessary.
Response: In our opinion, it is strongly related to the previous paragraph, because it is related to it. That is why we want to keep it in the handbook, because it does not take away from it, but enriches our knowledge.
Point: Line 382-386: It could be interesting to check correlations between the number of visits or duration and egg numbers laid in nests.
Response: I totally agree with you, that is why I completed this paragraph.
Point: Line 394-397: Repetition of M&M section. Please remove.
Ressponse: I agree, I removed it.
Point: Line 407: “standard deviation” They were not given on the tables. Should be added.
Response: I understand what you write. But I used the wrong term, so I'm deleting it from there. And it is not necessary to supplement the table.
Point: Conclusion part a repetition of results and discussion section. Please shorten it to one or two paragraph and give the main conclusion only.
Response: Indeed, in several cases, the repetition of the results is included in the conclusions chapter. Therefore, in agreement, I shortened it according to the request.
Point: Line 445: “I measured “ Not suitable for scientific writing. Please rephrase.
Response: I agree, I modified it.
Point: Line 448-456: Mostly Repetition of the results. Please remove.
Response: I agree, I deleted it.
Point: 458-460: Repetition of the results. Please remove.
Response: I agree, I deleted it.
Point: 461-472: Should be moved to discussion section.
473-477: Should be moved to discussion where it is suitable.
Response: I agree with you, so I moved it as requested
Point: 484: Based on my test; again not suitable for writing. Please rephrase.
Response: I agree, I modified it.
Point: 490-492: I would say, I found this conclusion far beyond available data which rely only the parental lines and hybrid of a breeder company. I appreciate the study which is highly valuable to show that layers coming from conventional selection strategies may not have good nesting behavior. And, this study does this. However, we need solutions not to frighten people.
Response: I agree with this line of thought.
Point: Line 493-494: “chosen” suggest to replaced with “selected” and “keeping” to “ housing conditions”.
Response: I agree, I modified it.
In the revised manuscript, you can view comments, replies to them, and any changes to the manuscript.
You are Reviewer 2, I have marked your comments in red.
Please see the attachment!
Author Response File: Author Response.docx
Reviewer 3 Report
Dear Editor,
The study is well planed and very relevant to the field of poultry. The topic is very important regarding poultry welfare and is a burning issue now a days.
The manuscript, however, contains a lot of language errors specially very lengthy sentences.
The conclusion of the study MUST be rewritten that should be brief. Because the already given conclusion is too lengthy.
The above suggestions needs to be corrected before accepting the manuscript for publication.
Regards,
Author Response
Response to Reviewer 3 Comments
Point 1: The study is well planed and very relevant to the field of poultry. The topic is very important regarding poultry welfare and is a burning issue nowadays.
Response 1: First of all, thank you for taking on the task of reviewing our manuscript. I am glad that you also find the work well planned and relevant.
Point 2: The manuscript, however, contains a lot of language errors specially very lengthy sentences.
Response 2: I agree that the manuscript contains several sentences that are too long and contains several linguistic errors. Thanks for bringing it to our attention. Several specific cases were also noted by the other two reviewers, and we reviewed the manuscript in detail. As a result, we deleted, shortened, transformed several sentences and corrected language errors.
Point 3: The conclusion of the study MUST be rewritten that should be brief. Because the already given conclusion is too lengthy.
Response 3: You are absolutely right. We also felt that the conclusions chapter could be a bit long. Furthermore, the other reviewers also drew our attention to this.
Following specific suggestions, we have deleted or moved parts that are repetitions of the results chapter in several places.
We have corrected the senteces and replaced the incorrect terms and statements with the correct ones.
Point 4: The above suggestions needs to be corrected before accepting the manuscript for publication.
Response 4: In accordance with your and other reviewers' constructive and helpful suggestions, we have completely revised tha manuscript where it was possible.
Thank you again for accepting the revision and for honestly drawing our attention to the errors that need to be corrected. This contributed to improving the content and quality of the manuscript. It was instructive for us, which we can use in our future work for the benefit of science and the profession.
You can check the corrections and any changes in the attached manuscript with comments.
In the revised manuscript, you can view comments, replies to them, and any changes to the manuscript.
You are Reviewer 3, I have marked your comments in green.
Please see the attachment!
Author Response File: Author Response.docx
Round 2
Reviewer 1 Report
I accept the revised version of the manuscript for publication.
Reviewer 2 Report
Most of the necessary changes have been made in revised version.
