Effects of Dietary Clostridium butyricum on Carcass Traits, Antioxidant Capacity, Meat Quality, and Fatty Acid Composition of Broilers
, Mengsi Du †, Xiaobing Wang, Junyong Wang, Jinzhuan Li, Xiaohan Jiang, Rijun Zhang and Dayong Si *
Round 1
Reviewer 1 Report
Manuscript ID: agriculture-1887620
Title: Clostridium butyricum, a Potential Antioxidant as a Feed Additive, Improves Carcass Traits, Antioxidant Capacity, Meat Quality, and Fatty Acid Composition of Broilers.
Generally, the study is well designed and description of sampling and analytical methods are enough detailed, and the results and discussion are well-organized.
Be sure all acronyms are defined.
L 25: remove “in broilers”
L 29: Define this abbr. “SFA” here not in L 30
L 49: global production of poultry meat was 35 percent of what …. ?
L53: change to “of poultry” to of poultry meat
L 40-45: this part should be moved to be before this sentence “It is imperative to conduct intensified searches for alternative natural growth promoters to sustain growth, health, and meat quality of chickens.”
L 56-58: Please rephrase his sentence “Probiotics become more important alternatives as feed additives because of their antimicrobial properties, anti-inflammatory, antioxidant, modulating the structure of host microflora and stimulating effects on the digestive systems of animals [5-7].”
L 63-64: Rewrite this sentence to be clear “Not only do its strong resistance against adverse environments within the gastrointestinal tract, but also it can create a beneficial environment in vivo.”
L 71: reword this term “with variations in its color”
L 79: change “can ameliorate” to “ameliorated”
L 100: please clarify the origin of strain isolation (chicken gut, or soil, etc.)
L 114-116: “broilers fed a basal diet supple- 114 mented C. butyricum at 2×108 CFU/kg feed (CBL), 4×108 CFU/kg of C. butyricum feed (CBM), 115 and 8×108 CFU/kg of C. butyricum feed (CBH).” Please rewrite it to be consistent.
L 126: change “three-layer cages” to “three-tier cages”
L 192-194: “The effect of CBL, CBM, and CBH as a feed additive on slaughter performance, dressing percentage, eviscerated percentage, breast and thigh muscle percentage, and abdominal fat percentage at day 39 of broilers (Table 2).” Incomplete sentence.
L196-197: “However, supplementation of C. butyricum tended to increase the breast muscle percentage and decrease the abdominal fat percentage of broilers.” Was this increase and decrease significant or not? Clarify with P value.
Table 2: Where is the P value? It is not presented there.
L 208-209: this statement is not clear. You mean concentrations of GSH-Px in blood or liver? However, I think that the authors should not say the feed supplements improved ….. if the differences between the groups were not statistically significant as shown in Table 3.
L 316-318: “The current study has indicated that dietary C. butyricum gained higher breast muscle and lower abdominal fat in broiler chickens, making it popular with the public because of its higher economic value”. Here and through the manuscript, the authors should confirm that such results were not statistically significant. You can use a proper way to indicate the positive effect of feed supplements in your study.
L 356: change “has been proved to reduce” to “reduced”
L 357-360: for “In the current study, we observed that adding C. butyricum to feed resulted in a redness increase and yellowness decrease in the breast muscle of broilers, which indicated that introducing C. butyricum as a feed additive could retain better meat color.”, there were no significant differences in yellowness between the groups.
Author Response
Please see the attachment. Many thanks.
Author Response File: 
Author Response.docx
Reviewer 2 Report
The study seems to be interesting but without any information about growth performance.
Why did you keep broilers in layer cages?
In terms of Antioxidant capacity I would advice comparison of 21st day and 39 day. Do you have samples from day 1 ? it would be very interesting to compare them.
Please show what is novelty in comparison with earlier studies except another chicken breed i.e. https://lipidworld.biomedcentral.com/articles/10.1186/s12944-015-0035-0
Author Response
Response to Reviewer 2 Comments
Dear reviewer,
Thank you for your kind and careful reviewing the manuscript (Agriculuture-1887620), titled “Clostridium butyricum, a Potential Antioxidant as a Feed Additive, Improves Carcass Traits, Antioxidant Capacity, Meat Quality, and Fatty Acid Composition of Broilers”.
Based on these comments and suggestions, we have revised all the problems you proposed and improved the manuscript seriously, incuding all the inappropriate contents.
Please see the attachment.
Best wishes and regards,
Sincerely,
Yang Tiantian
Author Response File: Author Response.docx
Reviewer 3 Report
The manuscript is very interesting, correctly written, and it deals with the very important and relevant issue. However, there are some general suggestions for authors related to the way that results are presented and explained. I suggest that author rewrite some parts of the Results, Discussion, Conclusion and Abstract in order to clarify and better explain the differences between groups. Besides that there are some minor remarks that should be corrected in the text.
General remark: In the whole manuscript and consequently in the abstract too, it should be clearly stated which level of inclusion of Clostridium butyricum (CB) caused positive or negative effect. There were 3 groups of CB and inclusion rate is very important, but the inclusion level was not discussed. It is not justified to state that CB has positive effect on some traits if only one of the three CB groups showed positive effect and the other two didn’t. Also, when it comes to dose response trials it is more appropriate to do the regression analyse than ANOVA, but ANOVA is also acceptable.
Next remark refers to comparison. I would suggest that in the discussion of the results authors should comment on the results relative to the Control group (group without any additive). If they got the positive results in some traits compared to antibiotic group, but not compared to the Control group, they cannot conclude that CB improves that trait ( for example Line 364). We can rather say that AB has negative effect on the trait That should be clearly emphasized in the text.
Authors should clearly distinguish the situations where the effect of CB on examined traits is significant and where is not. According to my opinion authors could state that effect is positive only if they got the significant difference (P<0.05). For example, phrase “tended to increase” (Line 20, Line 196) could mislead the readers if the P value is not showed. In the case f breast meat, the fact is that there were no significant effects of CB on breast meat and abdominal fat (Table 2).
Title: I would suggest to avoid the word improves in the title. It is formulated as a statement confirming the positive effect of Clostridium butyricum (CB) on examined traits, but the effect is still questionable. Readers could be mislead.
Lline 13: leave out the word potential
Line17 „bred“ should be „reared“
Line 40: consider „growth promoting“ instead of „growth-prompting“ ; stock farming should be livestock farming
Line 41: exclude word „enormous“
Line 51: polutry meat should not be considered as functionl food if it is not enriched by some beneficial product.
Line 81: sentence is not clear. CB should act as a potential antioxidant in poultry feed? Is that the point?
Line 108: sex of the chickens is not mentioned. This is important information especially when you have 11 birds per replicate
Line 138: sex of the bird in the sample should be mentioned
Lines 192-194: Sentence is not correct. Please rephrase
Line 196: please refer to the general comment
Table 2. Column with the P value is missing
Lines 212-214: please refer to the general comment
Line 228: sentence is too general and not supported
Lines 230/232: trends are not statistically estimated
Line 271: please refer to the general comment
Line 294-295 and 297: too general and not statistically confirmed
Lines 316/318: not statisticaly confirmed. That should be emphasized
Lines 338-340: please refer to the general comment
Lines 347-349: please check if this sentence is correct
Lines 358-359: please refer to the general comment
Lines 388-390: please refer to the general comment
Lines 410-412: please refer to the general comment
Conclusion: please refer to the general comment
Author Response
Response to Reviewer 3 Comments
Dear reviewer,
Thank you for your kind and careful reviewing the manuscript (Agriculuture-1887620), titled “Clostridium butyricum, a Potential Antioxidant as a Feed Additive, Improves Carcass Traits, Antioxidant Capacity, Meat Quality, and Fatty Acid Composition of Broilers”.
Based on these comments and suggestions, we have revised all the problems you proposed and improved the manuscript seriously, incuding all the inappropriate contents and mishanded statistics.
Please see the attachment.
Best wishes and regards,
Sincerely,
Yang Tiantian
Author Response File: Author Response.docx
Round 2
Reviewer 1 Report
L 23: AM not CBL, be careful.
L 20-24: “Broilers in the CBH group had a higher liver total superoxide dismutase (T-SOD) concentration at day 21 than those in the CON, CBL, and CBM groups, a higher liver catalase (CAT) concentration at day 21 than those in the CON and CBL groups, a higher liver total antioxidant capacity (T-AOC) at day 39 than those in the AM group, but lower liver malondialdehyde (MDA) content on day 39 than those in the CON and CBL groups (P < 0.05).” Divide it into two sentences.
Serum antioxidant (Table 3) were not presented in the abstract
There are some significant results (pH45min, pH24h, and Drip loss) in Table 4 were not summarized in the abstract.
L 32: CBN….? I think you mean CON. Please be careful.
Significant differences of ΣMUFA in breast muscle should be shown in the abstract.
L 20-38: This part of abstract should be rewritten. Avoid the long sentences, typing error, and consider adding all the significant results.
L 54: It should be “global production of poultry meat was 35 percent of meat production in 2019”
Your response to Point 4 is not clear. Therefore, in line 58, please change “nutritive value of poultry” to be “nutritive value of poultry meat”.
L 60-62: “Probiotics become more important alternatives as feed additives because they play a vital role in anti-bacteria, anti-inflammation, antioxidant, modulating the structure of host microflora and stimulating the digestive systems of animals” this sentence grammatically is not correct. Please change it to “Probiotics become more important alternatives as feed additives because they play a vital role in enhancing the anti-bacterial, anti-inflammatory, and antioxidant effect, modulating the structure of host microflora and stimulating the digestive systems of animals”
Use a consistent form for the given names used for the fatty acids in the text and Tables. For example, C20:3n-6 and C20:3n6
Author Response
Dear reviewer,
Thank you for your kind and careful reviewing the manuscript (Agriculuture-1887620), titled “Clostridium butyricum, a Potential Antioxidant as a Feed Additive, Improves Carcass Traits, Antioxidant Capacity, Meat Quality, and Fatty Acid Composition of Broilers”.
Based on these comments and suggestions, we have revised all the problems you proposed and improved the manuscript seriously, incuding all the inappropriate contents.
Please see the attachment.
Kind regards,
Sincerely,
Yang Tiantian
Author Response File: Author Response.docx
