Fatty Acid Content and Oxidative Stability in Eggs and Breast Muscle of Sasso Chickens Fed Different Levels of Dodonaea angustifolia Polyphenol in Flaxseed-Enriched Diets
, Negussie Retta 2, Wondmeneh Esatu 3, Henock Woldemichael Woldemariam 4,5, Nicholas Ndiwa 6, Olivier Hanotte 3,7,8, Paulos Getachew 2,*, Dirk Dannenberger 9,†and Steffen Maak 9,†Round 1
Reviewer 1 Report
Comments and Suggestions for Authors1. Some grammars and writings should be checked, revised and polished throughly. Here are some examples in the abstract.
Ex. line 22, adding plant polyphenol as a natural antioxidant…
Ex. line 30, in DA8 were significantly (p < 0.05) increased…..
Ex. line 31, angistifolia polyphenol had no significant effects….
Ex. line 32-33, was observed in hens with an increased dose of D. angustifolia 32
polyphenol extracts.
Ex. line 34-35, feeding different doses of D. angustifolia extracts had no effects on egg yolk lipid peroxidation.
2. In Table 1, what is the calculation of fatty acid composition? By wt/wt or by molar ratio? It is suggested to expression the composition by molar ratio since the length of chain, for example C14 and C18 with 4-carbon difference in molecular weight.
3. The authors need to rationalize why only 1 time point (at the end) was selected for egg collection for analysis. The trial was lasted for 8 weeks, at least an additional time point should be selected for monitor the change of fatty acid content of eggs along the time course.
4. The authors need to rationalize why CaHPO4 was not formulated in the diet?
5. In Figure 1, where are statistical significance marks?
6. Where is the preparation procedure of D. angustifolia polyphenol extracts?
Comments on the Quality of English LanguageModerate editing of English language required
Author Response
Please see the attachment.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsGeneral
The manuscript presented the effects of Dodonaea angustifolia inclusion in a flaxseed enriched diets on fatty acids content and oxidative stability of eggs and breast muscle of Sasso Chickens. The subject is of interest not only from the point of view of farmers, but also from the point of view of consumers. Thus, the manuscript requires some improvements. The author needs to pay more attention to writing details. Also, the manuscript has a lack of important information regarding the Materials and Methods. Additionally, there are no data on the antioxidant compounds of Dodonaea angustifolia, which is a key focus of the manuscript. This is especially important given that the discussions also address its antioxidant composition. Moreover, this study was designed using inclusion techniques, but it appears that the diets were not balanced, as the totals are the same for all four diets, yet no ingredient was modified. Considering that the authors studied the effects of flaxseed and Dodonaea angustifolia on the fatty acid profile and oxidative stability of breast and eggs, it is essential that the physicochemical composition of both feed sources to be tested and discussed.
Specific
Abstract
Line 22: Avoid using the word “antioxidant” consecutively.
Line 27: The abbreviation D. angustifolia must be presented in text before using it.
Line 34: Avoid using the word “doses” consecutively.
Line 34: Delete a space before the word “doses”.
Introduction
Line 54: Delete a space before the word “into”.
Line 58: Delete “of”.
Line 60: Delete “of”.
Lines 58-60: Please rephrase this paragraph to make it clearer.
Line 61: Delete a space before the word “and”.
Line 68: Delete a space before the word “However”.
Line 72: The references must be written according to the journal's requirements.
Lines 71-74: Please rephrase this paragraph to make it clearer.
Lines 81-83: Maybe “Therefore, this study aimed to evaluate the effect of the D. angustifolia polyphenol extract at doses of 0 mg, 200 mg, 500 mg, and 800 mg in a flaxseed-enriched diet on fatty acid content and oxidative stability in the breast muscle and eggs of slow-growing Sasso chickens.”
Materials and Methods
Line 89: Delete a space before the word “AppliChem”.
Line 89: Add a space after “≥”.
Lines 113-116: Rephrase this paragraph to make it clearer.
Please provide the details regarding the experimental conditions: The temperature, and humidity.
Please specify the origin of flaxseeds and Dodonaea angustifolia.
Table 1: The author stated that D. angustifolia was added to the experimental diets at various levels. However, it is not clear from Table 1 if the diets were balanced, given that the totals are the same and no ingredients from the diets were changed.
The fatty acid composition from Table 1 could be presented in a separate table to be clearer.
Chapter 2.3. Add more details about the methods used. The results regarding the ash content and total nitrogen content are not presented.
Chapter 2.4: Add more details to the methods used.
Line 172: Please use the degree sign for 55 °C.
Line 177: Write the numbers in chemical formulas as subscripts: K2CO3.
Line 180: Write the numbers in chemical formulas as subscripts.
Line 188: Present the producer and the origin country for “Precellys Evolution homogenizer.”
Line 189: Present the producer and the origin country for “Pyrex tubes”.
Line 202: The reference must be written according to the journal's requirements.
Lines 203, 204, 208: Write the numbers in chemical formulas as subscripts.
Line 214: Please present the origin country of PerkinElmer Clarus 680 gas chromatograph.
Line 231: Delete the doubled word.
Line 233: 200 µL of thiobarbituric acid (TBA)…. were add?
Line 236: What kind of tube?
Line 236: Please provide details of the sample preparation method.
Line 239: Please provide the details of the plates’ reader.
Line 244: Provide the producer and the origin country of Gen5 software (version 3.10, 2020).
Line 250: Provide the producer and the origin country of RStudio version 2021.9.0.351.
Results
Table 2: Please write the abbreviations of the experimental diets in a uniform mode.
For the results regarding the oxidative stability in breast muscle and egg yolk is not presented the statistical analysis.
Discussions
Lines: 323-326: Rephrase this paragraph to be clearer.
Lines 327-329: What can be the explanation for these differences?
Lines 332-333: Present the inclusion rate of the ingredients from the references.
Lines 336-337: Present the inclusion rate of the ingredients from the references.
Line 341: What was the inclusion rate of flaxseeds in reference [18]?
Lines 350-356: The authors presented that the alpha-tocopherol can lead to a lower content of n3-fatty acids, but the results showed an increase in their content in the breast and no statistical differences for egg yolk. Also, the authors presented the Dodonaea angustifolia as a powerful antioxidant source, but there is no data regarding its composition in antioxidants.
Lines 358-361: Once more, the author discusses the results because of the high polyphenol content of Dodonaea angustifolia, yet there are no data on this in the study.
Conclusion
In this chapter can be presented the impact on consumers and the future perspectives.
Comments for author File: Comments.pdf
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Reviewer 3 Report
Comments and Suggestions for AuthorsThe study aimed to the effects of D. angustifolia polyphenol extract levels in flaxseed enriched diets on fatty acid content and oxidative stability in meat and eggs of Sasso chickens. Chickens received 0, 200, 500, or 800 mg D. angustifolia extract/kg diet. Results showed that the breast muscle content of docosahexaenoic acid (DHA, C22:6n-3) in Sasso chickens that received 200 e 500 mg/kg diet and eicosapentaenoic acid (EPA, C20:5n-3) in Sasso chickens that received 800 mg/kg diet, significantly (p < 0.05) increased compared to those who did not receive. Feeding D. angistifolia polyphenol levels had no significant effect on egg yolk n-3 PUFAs content. However, a decrease (p < 0.05) in egg yolk n-6 PUFAs was observed for an increase in the dose of D. angustifolia polyphenol extract. In breast muscle, feeding on 500mg/kg decreased lipd peroxidation (p < 0.05) compared to the control diet. However, feeding different doses of D. angustifolia extract doses had no effect on egg yolk lipid peroxidation.
General concept comments
The article is original and there are practically no studies on this possible additive for poultry. The article will be of great contribution, as there is a gap in the effects of plant extracts with antioxidant potential and the possible doses for use. The design was described and some important information was cited from other articles in the group. I consider that the article needs some information to improve understanding.
Specific comments
Line 110: What were the design blocks?
Line 120-122: Why was it necessary to include 75 g of flaxseed in the description of the treatments? If it is included in all treatments like any other ingredient? If it is to characterize the inclusion of PUFA sources, just inform it in the text or in the footnote of the table. In fact, the diet was enriched with PUFA and not with the ingredient.
It is not common to slaughter laying hens at 35 weeks. Was egg production not evaluated? Why slaughter at this age? Were the production and carcass yield data not analyzed?
312: If it was not significant, it should not be mentioned, as it may generate a confounding factor of 11% in DA2 (p > 0.05). Please insert the letters to identify the statistical differences in the graph.
Remove current study in line 324-325, because already mentioned in line 323.
Line 321: In general, the discussion needs to be improved considerably, as there were very high changes in the concentrations of fatty acids, especially in the muscle and less so in the eggs. Why is this? The authors should discuss and justify the answers obtained, not just compare them with other studies. What is the biological explanation for this change, reduction or increase in intestinal absorption by the bird? Reduction of oxidation in the muscle and change in the FA profile? Two months is not enough to observe changes in the eggs. The authors do not even discuss the composition of the D. angustifolia extract. What are the main phenolic and flavonoid compounds of D. angustifolia? What are the effects of these compounds that can justify the answers obtained? There are many articles to use in the discussion, instead of comparing with extracts from other sources that do not even have a similar composition to D. angustifolia. The inclusion of flaxseed was a point that was highly highlighted in the title of the article, but was little addressed in the discussion. What is the potential for incorporating dietary fatty acids into meat and eggs? This can also interfere with the answers obtained.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Reviewer 4 Report
Comments and Suggestions for AuthorsThe manuscript provides interesting information in the field of use of plant polyphenol as natural antioxidant in chicken diet. In my opinion, some minor revisions to the text are necessary.
Throughout the manuscript:
I suggest insert authors when you write for example: „was described [36]”, „reported by [14].
I suggest remove words “recent/recently” when you indicate the reference.
When you write: „decreased”, „increased”, „no effect”, etc., please indicate the significance level. You can omit the word "significantly" when you indicate the significance level.
Keywords
I suggest including information about Dodonaea angustifolia and the type of samples (meat, eggs). Moreover, I suggest replace „n-3 PUFA” with „fatty acids”.
Introduction
Line 58: Please remove m in „chickens”.
Line 60: Please remove m in „of”.
Materials and Methods
Line 123: Latin term should be italicized.
Line 149: The modifications must be describe.
Line 180: Please insert a space between number and unit.
Results
Table 2: Please check the letter designations for the statistical significance of differences. The letter "a" should indicate a higher value
Discussion
Lines 324-325: Please remove „in the current study”.
Lines 334-336: Should be used in the Results section.
Lines 358-360: Should be used in the Results section.
References
Latin names should be italicized.
Please format it in accordance with the journal's editorial guidelines.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Comments and Suggestions for AuthorsMost of comments are answered
Comments on the Quality of English LanguageMinor editing of English language required
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsI have read the revised manuscript and appreciate the authors' efforts to improve the work; however, there remain some major concerns.
Conventionally, a basic ingredient of the ration is partially replaced with the supplement. If this was the method used, it should be reflected in the ration, and adjustments should be made. In case 2, if the supplement was added on top of the ration, the consumption must be calculated, and the supplement must be added proportionally. What was the procedure followed? Please detail the procedure in Chapter 2.2.
Additionally, there are still some corrections to be made, such as:
Line 27: The abbreviation D. angustifolia must be presented in text before use it, for example, line 26 “Dodonaea angustifolia (D. angustifolia)”
Line 77: The reference should be written according to journal requirements.
Please write the abbreviations of the experimental diets in a uniform mode, in all tables of the manuscript.
The authors need to use the degree sign for the temperature’s expression. Please revise this issue throughout the entire manuscript.
The authors must mention the humidity and temperature to which the animals were exposed during the experiment, details that should be added in Chapter 2.2.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
