Optimization of the Composition of a Novel Bioactive Silage Produced by Mixing of Ground Maize Grains with Olive Mill Waste Waters, Grape Pomace and Feta Cheese Whey

Round 1

Reviewer 1 Report

The manuscript describes the production of silage using agro-industrial wastes, several recipes were tested and using mathematical modelling the best combination of ingredients was found. In general the analysis are correct, and English usage is good but some parts require improvement to make it easier to read.

I found the introduction and discussion sections too long. In the discussion section there are several parts that seems to be results more than discussion (4.6, 4.7 and first paraghraph of 4.8)

Specific comments

Line 72: Please rephrase the sentence “In Gerasopoulos et al…..” It is four lines long.

Lines 73, 79 and 81: OMWW was explained in line 39 please remove.

Lines 84, 85, 90,91 and so on: there is a dot instead of comma in several parts of the manuscript, please check.

Line 98: Sentence “In this study….” Can be deleted, no relevant information is provided.

Lines 111 through 123: First what was analyzed in the publications is described, then which where the results. Please summarize indicating only the relevant results, the introduction is too long.

Figures 3, 4, 5 and 6: Please use the same label for silage/sample 67.

Figure 4: Please add the y axis label, there is a -1 silage/sample and correct “he” for “the” in the text inserted on the graph.

Figure 6: Plase center the y axis label, there is also a typo in exponent.

Figure 9: Please center the column labels

Figure 10: Please check Day Uppercase

Line 735 through 798: please describe results from other publications relevant to discuss the findings of the present manuscript. It is not necessary to provide the aims, or methods used in the manuscripts cited.

Author Response

REVIEWER1

Comments and Suggestions for Authors.

I found the introduction and discussion sections too long. In the discussion section there are several parts that seems to be results more than discussion (4.6, 4.7 and first paraghraph of 4.8) The introduction and the Discussion part of the paper were shorten following the reviewer comments

Specific comments

Line 72: Please rephrase the sentence “In Gerasopoulos et al…..” It is four lines long.

In Gerasopoulos et al. [7], broilers administrated feed supplemented by maize silage produced with inclusion of olive mill wastewaters (OMWW) retentate or permeate  had significantly lower protein oxidation and lipid peroxidation levels and higher total antioxidant capacity in plasma and tissues compared to control group.

Rephrased to

In Gerasopoulos et al. [7], broilers administrated feed supplemented by maize silage produced with inclusion of olive mill wastewaters (OMWW) retentate or permeate. According to their findings the experimental group broilers  had significantly lower protein oxidation and lipid peroxidation levels and higher total antioxidant capacity in plasma and tissues compared to control group.

Lines 73, 79 and 81: OMWW was explained in line 39 please remove.

removed

Lines 84, 85, 90,91 and so on: there is a dot instead of comma in several parts of the manuscript, please check.

Corrected. Dots removed and comma put instead

Line 98: Sentence “In this study….” Can be deleted, no relevant information is provided.

This phrase was removed in the revised manuscript

Lines 111 through 123: First what was analyzed in the publications is described, then which where the results. Please summarize indicating only the relevant results, the introduction is too long.

THE ORIGINAL TEXT

Guerra-Rivas et al .[12] and Jeronimo et al .[13] provided information on the use of grape pomace in the diet of sheep with respect to the fatty acid profile and oxidative stability of meat. Makri et al [14] examined the potential antioxidant effects of a feed supplemented with grape pomace (GP) in chickens. The results indicated that feed supplemented with GP decreased oxidative stress-induced toxic effects and improved chickens’ redox status. and so it may also improve their wellness and productivity. On the other hand. this exploitation of GP may solve problems of environmental pollution in areas with wineries. Furthermore, Kafantaris et al [15] carried out a study to investigate whether lambs’ feed supplemented with grape pomace enhances the antioxidant mechanisms and reduces the growth of pathogenic bacteria. The results showed that lambs fed with experimental diet had significantly increased antioxidants mechanisms in blood and tissues as shown by increases in CAT and GSH compared to control. Moreover. lambs fed with the experimental diet exhibited decreased oxidative stress-induced damage to lipids and proteins as shown by decreases in TBARS and CARB respectively.

REDUCED TO

Guerra-Rivas et al .[12] and Jeronimo et al .[13] provided information on the use of grape pomace in the diet of sheep with respect to the fatty acid profile and oxidative stability of meat. Makri et al [14] examined the potential antioxidant effects of a feed supplemented with grape pomace (GP) in chickens. Furthermore, Kafantaris et al [15] found out that lambs’ feed supplemented with grape pomace enhances the antioxidant mechanisms and reduces the growth of pathogenic bacteria for the animals.

Figures 3, 4, 5 and 6: Please use the same label for silage/sample 67.

The label control was put in the sample 67 of Figure 4 and now all the Figures are in line

Figure 4: Please add the y axis label, there is a -1 silage/sample and correct “he” for “the” in the text inserted on the graph.

Corrected

Figure 6: Plase center the y axis label, there is also a typo in exponent.

Corrected. The y axis label was centered

Figure 9: Please center the column labels

Corrected. The column label was centered

Figure 10: Please check Day Uppercase

Corrected

Line 735 through 798: please describe results from other publications relevant to discuss the findings of the present manuscript. It is not necessary to provide the aims, or methods used in the manuscripts cited.

This part of the paper was shorten and become more focused according to your suggestion

Reviewer 2 Report

Dear authors, you have done a comprehensive silage test with different agroindustrial wastes, which can be used in animal nutrition.

In Table 4 you describe the mixture of the different variants. You can ad the total DM of the mixture. The water activity has an effect on the resulting pH after the silage process. Also the buffercapacity of the mixture would be of interest.

How is grape pomace produced ? the DM of 3% is very low?

The test was stopped after 30 days (normal are 90days) (your results show the silageprocess to be finished at that time.

You investigated yeast and moulds after 30 days. the KBE dropped down which is normal, but it is not possible to eliminate yeast an moulds totally by a low pH.

this should be written here. Interesting would have been the test of aerobic stabillity in a isolated box. This is a relevant factor for the practical use as feedstuff. (can not be done in this test now)

Author Response

REVIEWER 2

Αρχή φόρμας

Τέλος φόρμας

Αρχή φόρμας

Author's Reply to the Review Report (Reviewer 2)

Dear authors, you have done a comprehensive silage test with different agroindustrial wastes, which can be used in animal nutrition.

In Table 4 you describe the mixture of the different variants. You can ad the total DM of the mixture. The water activity has an effect on the resulting pH after the silage process. Also the buffercapacity of the mixture would be of interest.

In Table 9 it is presented the moisture content of the silage which is approx. 43 % w/w which means that the dry matter is 57% w/w. The water activity was not measured but it is a good idea to take it into account for future works. The dry matter of silage was emsured not only for the optimized sample but also in about 10 samples to have an idea about the range of thye values. The range of measured values  was very narrow from 56,4 to 57,6

How is grape pomace produced ? the DM of 3% is very low?

This was corrected total solids are 43% w/w the first digit was forgotten

The test was stopped after 30 days (normal are 90days) (your results show the silage process to be finished at that time.

The optimization of silage seems to have shorten the period of ensilage but on top of this we measure the silage parameters and its microbial condition with good results after 3 months from the end of ensilage (30 days)

You investigated yeast and moulds after 30 days. the KBE dropped down which is normal, but it is not possible to eliminate yeast an moulds totally by a low pH

The yeast and mold count was taken again after 90 days from the end of ensilage and it was zero. This maybe due to the optimization of silage composition and also due to the high amount of antagonistic lactic acid bacteria.

this should be written here. Interesting would have been the test of aerobic stabillity in a isolated box. This is a relevant factor for the practical use as feedstuff. (can not be done in this test now)

We fully agree with this remark and we take into account this in future works as it is really important.

Τέλος φόρμας

Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

Dear Authors, Thank you for answering the questions.

For the next research tests in similar design it would be fine to add a test for aerobic stabillity. In my experience this is an important test to evaluate the practical use of the silage to feed the animals for a longer feed out period.

Author Response

Thank you very much for your comments. We highly appreciate your valued opinion and time for review our manuscript.