Seasonal Variations of Milk Composition of Sarda and Saanen Dairy Goats

Round 1

Reviewer 1 Report

See file upload

Comments for author File: Comments.docx

Author Response

We would like to thank the reviewer for the careful review of our manuscript and for the helpful suggestions that have greatly improved the manuscript. Two references have been added, a table and a paragraph for statistics (Materials and Methods section). English has been revised and long sentences have been split into shorter sentences. The discussion section has been divided in sub-sections. Responses to the reviewer are listed in the attached file.

Author Response File: Author Response.pdf

Reviewer 2 Report

both the methodology and the objective are not new and it is framed in a very specific territory.

However, the results can be exploited to improve the quality of the derived products of these area.

English should be revised and sentences should be rewritten in order to be clearer, some of them are hard to follow.

The study of the seasonality on production must be accompanied by a more detailed analysis of production and management conditions.

Two breeds are compared at the same time, each with a different production system (semi-extensive/semi-intensive).

Some conclusions of the study are based on mere hypotheses that cannot justify the results obtained.

I believe that this study can be published, revised and summarized, as a note since it could help farmers/producers in the area to know the quality of the milk obtained and better adjust its technological adaptability for transformation into dairy products.

Author Response

We would like to thank the reviewer for revising our manuscript. Two references have been added, a table and a paragraph for statistics (Materials and Methods section). English has been revised and long sentences have been split into shorter sentences. The discussion section has been divided in sub-sections. Responses to the reviewer are in the attached file.

Author Response File: Author Response.pdf

Reviewer 3 Report

The topic of this manuscript is interesting for readers, although the quality and the scientific significance of this manuscript must be improving. The explanation is weak, I find a lot of problematic parts, mainly in the Materials and Methods section. Description of animal experiment and sample investigation are disordered and imprecise.

List of remarks:

Introduction

Line 46: need stronger reference!

Lines 47-48: need rewriting the description of the characteristics of the Sarda breed!

Line 52: what does mean: “difficult areas”?

Materials and methods

How many samples were collected and investigated? See line 65: 7065, later: lines 67-68 3783+3285 (7068), line 85: 7068, but in Table 1: 3776+3277 (total: 7053)?

Line 66: this sentence is not clear! Need rewrite this sentence! Stable=farms?

How milked the animals? Hand or machine? No data about nutrition! What mean semi-extensive and semi-intensive method? Saanen: how were kept these animals?

Lines: Please describe the analytical methods for milk analysis, especially SCC and fatty acid composition! Presently, these are very imprecise (e.g. name of device, name of producer company, etc.) !

Statistical evaluation is totally absent!

Results

Line 84-85: should be put into Materials and Methods section with Figure 1!

Line 84-85: how many years of data were evaluated? 2015-2019 is 5 years?

Table: missing the units! NaCl: how measured? SCC(log), TBC (log): wrong data! Because 1823 SCC means 1823 thousand cells! So, more than log 6!!! Please add a P-value column!

Figure 2-5: Author should include an error bar in all Figures!

Figure 2: Sarda’s fat and protein content was more consistent than Saanen, but the SD value of Saanen is lower compared to Sarda! Why?

Line 136: “behavior”? Incorrect phrase!

Figure 4: why Saanen milk fat PUFA content was higher than Sarda? But Sarda goats were kept on pasture (grass contained high ratio of PUFA; see line 323)

Lines 201-209: need more results!

Lines 270-280: this section is not comprehensive! Need more revision!

Line 301: no data nutrition of goats!

 

Author Response

We would like to thank the reviewer for the careful review of our manuscript and for the helpful suggestions that have greatly improved the manuscript. Two references have been added, a table and a paragraph for statistics (Materials and Methods section). English has been revised and long sentences have been split into shorter sentences. Responses to the reviewer are listed in the attached file.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

The authors have greatly improved the paper and the discussion is better organized. I appreciate the added correlation table. It highlights the influence of lactose and NaCl, which the authors have included in the discussion.

My only suggestion is in the statistical model.

Line 81-88 - Statistics. The description of the statistical model is inadequate. The study had two (three actually with the Sarda cross) breeds across 4 years (October 2016 to September 2020). The data is presented for month for each breed, therefore the ANOVA model should have breed, month, year. In addition, samples were repeatable samples from farms across year. Variation across farm would be significant and across years may be variable. Calculating mean differences across years and months may be greatly influenced by different farms included across years and months. You need to have some control in your model for farm, year, month in addition to comparison across breed.

In fact, samples per month by breed in figure 1 are different. Variances may also be different for making comparisons. A fixed model, which you seem to have used, versus a mixed model would yield more robust comparisons.

The means across breeds would be confounded by the difference in monthly number of samples. The farms sampled within month would also confound the mean comparisons.

Table 1: the means would be more appropriate as a least square means controlling for year, farm, month, in addition to breed.

This is the only suggestion I have.

Author Response

I thank the reviewer for his comments.

Responses are in the attached file.

Author Response File: Author Response.docx

Reviewer 3 Report

The quality and the scientific significance of this manuscript were improved by authors.

Author Response

We thank the reviewer for accepting our revisions