A Meta-Analysis of 3-Nitrooxypropanol Dietary Supplementation on Growth Performance, Ruminal Fermentation, and Enteric Methane Emissions of Beef Cattle
, Juan Eduardo Godina-RodrÃguez 2, Jonathan Raúl Garay-MartÃnez 3, Lorenzo Danilo Granados-Rivera 4, Jorge Alonso Maldonado-Jáquez 5 and Alejandro Lara-Bueno 1,*Round 1
Reviewer 1 Report
Comments and Suggestions for Authors - Figure 1. Part is not visible- Table 1. Provide the body weight or age of fattened animals
- 15 publications were included. Check whether the research results
have not been used more than once (McGinn is a co-author in 9 publications!)
- In my opinion, the conclusion is too optimistic. We don't know what
they would look like if fattened for a longer period of time.
Author Response
Response to Reviewer #1:
We would like to thank the reviewer for the careful and thorough reading of this manuscript and for the thoughtful comments and constructive suggestions, which help to improve the quality of this manuscript. Our response follows (the reviewer's comments are in italics).
Comments and Suggestions for Authors
Comment 1. - Figure 1. Part is not visible.
Response: The Figure has been adjusted on the page and is now visible. It is worth mentioning that this figure was placed correctly from the first version of the manuscript; however, the editorial team was the one who moved it to the right, leaving a part not visible.
Comment 2. - Table 1. Provide the body weight or age of fattened animals.
Response: Most studies did not report the animals' ages. Therefore, Table 1 includes only the body weight of the fattened animals.
Comment 3. 15 publications were included. Check whether the research results
have not been used more than once (McGinn is a co-author in 9 publications!).
Response: All references have been carefully evaluated and it has been found that no publication has been used more than once.
Comment 4. ·In my opinion, the conclusion is too optimistic. We don't know what
they would look like if fattened for a longer period of time.
Response: Considering this comment, we have complemented our conclusion in lines 400-401, in which the following information was added: “However, more long-term studies are necessary to corroborate the anti-methanogenic effect of 3-nitrooxypropanol over long periods.”.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsThe authors conducted the meta-analysis of 3-nitrooxypropanol dietary supplementation in beef cattle on animal growth performance, ruminal fermentation, as well as enteric methane emissions.
The presented results are outcome of thorough literature search in order to build database that was used as a basis for statistical analysis. The literature search process is well described together with all used methodology. As climate changes are obvious and global warming is a critical environmental issue that affects animal production, the topic of preventing enteric methane emissions in animal production by nutritional strategy is topic of interest for professionals as well as people of academia that work in a field of animal nutrition.
The layout of the paper is sufficiently good as well as the English language. The presented methodology is detailed and clear. The presented results back up the conclusions and they are given in a manner that can be easily understood. I would suggest putting some additional explanation of used abbreviations in Table 5 (DMI) and Figures 2 and 3 (CI) so that table and figures can be clear to potential readers as a whole.
Comments on the Quality of English LanguageMinor editing of English language required.
Author Response
Response to Reviewer #2:
We would like to thank the reviewer for careful and thorough reading of this manuscript and for the thoughtful comments and constructive suggestions, which help to improve the quality of this manuscript. Our response follows (the reviewer's comments are in italics).
Comments and Suggestions for Authors
The authors conducted the meta-analysis of 3-nitrooxypropanol dietary supplementation in beef cattle on animal growth performance, ruminal fermentation, as well as enteric methane emissions.
The presented results are outcome of thorough literature search in order to build database that was used as a basis for statistical analysis. The literature search process is well described together with all used methodology. As climate changes are obvious and global warming is a critical environmental issue that affects animal production, the topic of preventing enteric methane emissions in animal production by nutritional strategy is topic of interest for professionals as well as people of academia that work in a field of animal nutrition.
The layout of the paper is sufficiently good as well as the English language. The presented methodology is detailed and clear. The presented results back up the conclusions and they are given in a manner that can be easily understood. I would suggest putting some additional explanation of used abbreviations in Table 5 (DMI) and Figures 2 and 3 (CI) so that table and figures can be clear to potential readers as a whole.
Response: Thank you very much for your valuable review and suggestions. An additional explanation of Table 5 has been added (See line 228). Likewise, in lines 253 and 257, the abbreviation CI in Figures 2 and 3 has been clarified.
Author Response File: Author Response.pdf
