Assessment of the Nutrient Value and In Vitro Rumen Fermentation Characteristics of Garlic Peel, Sweet Potato Vine, and Cotton Straw
Round 1
Reviewer 1 Report
Comments and Suggestions for Authors
This article investigated the nutrient value and rumen fermentation parameters of three agricultural by-products, and demonstrated sweet potato vines exhibit higher feeding value and superior rumen fermentation performance. The manuscript is an original and well-done research on development and utilization of non-conventional feed resources for ruminants. The hypothesis is not very novel, but the area of research is very important. The results of the study have strong potential practical application value, and provide scientific basis and technical support for developing of non-conventional feed resources. However, I think there are still a few shortcomings in the current manuscript.
Major Comments:
1. In the introduction, I suggest including a brief description on these by-products yields. Additionally, supplementing the palatability information of these three unconventional roughages for cattle and sheep can provide a basis for the subsequent processing of these roughages.
2. Regarding the introduction of the three by-product ingredients, what is their state before drying? Have they already undergone drying treatment? When preparing air-dried samples, what is the sequential order of drying: should they be ground first and then dried, or dried first and then ground?
3. When evaluating the effective energy value of feed, although the author has determined the gross energy of the feed using an adiabatic bomb calorimeter, why is the estimation of TDN still used to calculate other effective energy values?
4. The author described the yield of rumen microbial protein in the results section, but did not detail the specific measurement methods in the materials and methods section.
5. In the evaluation of relative feed value (RFV) and relative forage quality, we understand that the RFV of alfalfa at full bloom is set at a value of 100. In this study, except for garlic skins, all RFV values were above 100. This indicates that the nutritional value of these two feeds is higher than that of alfalfa at full bloom. However, the author did not expand on this in the discussion.
6. In the discussion, the three by-product ingredients selected in this study need to be compared more extensively with other roughages. For instance, it would be useful to determine whether the nutritional values of alfalfa, Leymus chinensis, and oat grass studied by others are comparable to those of these four roughages. This could also help identify some of the discrepancies in the experimental results.
Minor comments:
1. Line 18, typo "fiber"
2. Line 25, typo " NH3-N "
3. Line 29, typo " by-products"
4. 3. Line 75, " Ipomoea batatas L." should be denoted by italicized text
Comments on the Quality of English Language
Minor editing of English language required.
Author Response
Major Comments:
- In the introduction, I suggest including a brief description on these by-products yields. Additionally, supplementing the palatability information of these three unconventional roughages for cattle and sheep can provide a basis for the subsequent processing of these roughages.
Reply: Thank you for your kind suggestion. We have supplemented the relevant content, please see Line 56-57, 64-66, 75-77, 91-93.
- Regarding the introduction of the three by-product ingredients, what is their state before drying? Have they already undergone drying treatment? When preparing air-dried samples, what is the sequential order of drying: should they be ground first and then dried, or dried first and then ground?
Reply: The three feed ingredients were naturally air-dried before drying. During the preparation of air-dried samples, the sequence involved crushing the ingredients first, followed by drying.
- When evaluating the effective energy value of feed, although the author has determined the gross energy of the feed using an adiabatic bomb calorimeter, why is the estimation of TDN still used to calculate other effective energy values?
Reply: The gross energy results obtained using the oxygen bomb calorimeter are more accurate, whereas the results estimated by formulas show significant discrepancies with the measured values. Therefore, we used the measured values for total energy. Energy value indicators such as DE, ME, NEm, NEg, and NEL cannot be directly measured through in vitro experiments and require animal metabolism trials for accurate determination. In vitro experiments can only estimate these energy values based on nutritional composition using formulas.
- The author described the yield of rumen microbial protein in the results section, but did not detail the specific measurement methods in the materials and methods section.
Reply: Revised. The measurement method of microbial protein has been added. Please see Line 187-188.
- In the evaluation of relative feed value (RFV) and relative forage quality, we understand that the RFV of alfalfa at full bloom is set at a value of 100. In this study, except for garlic skins, all RFV values were above 100. This indicates that the nutritional value of these two feeds is higher than that of alfalfa at full bloom. However, the author did not expand on this in the discussion.
Reply: Thank you for your kind suggestion, we have rewritten this part, please see Line 281-288.
- In the discussion, the three by-product ingredients selected in this study need to be compared more extensively with other roughages. For instance, it would be useful to determine whether the nutritional values of alfalfa, Leymus chinensis, and oat grass studied by others are comparable to those of these four roughages. This could also help identify some of the discrepancies in the experimental results.
Reply: We agree with your idea. We have supplemented the relevant discussion content, please see Line 256-258, 270-273, 290-292.
Minor comments:
- Line 18, typo "fiber"
Reply: Revised.
- Line 25, typo " NH3-N "
Reply: Revised.
- Line 29, typo " by-products"
Reply: Revised.
- 3. Line 75, " Ipomoea batatas L." should be denoted by italicized text
Reply: Revised.
Comments on the Quality of English Language
Minor editing of English language required.
Reply: Revised.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for Authors
Dear Authors,
Your manuscript entitled "Assessment of the Nutrient Value and In Vitro Rumen Fermentation Characteristics of Garlic Peel, Sweet Potato Vine and Cotton Straw" is addressing an interesting topic of research. It might be considered suitable for publication in Ruminants after major revision. Please, see below a list of comments/suggestions to be applied by you before accepting it to be published. Deep revision is needed in Materials and Methods. Important information is lacking. Full description is required.
Yours sincerely,
Reviewer.
L14 Write 'in vitro' in italics.
L16 Replace 'Ash' by 'ash'.
L17 Replace ', and the' by ', while the'.
L18 Replace 'were highly' by 'were'.
L19 Replace 'the other two feeds' by 'the others'.
L21 Write 'in vitro' in italics.
L25 Replace 'The sweet' by 'the sweet' and put 3 in subscript in 'NH3'.
L28 Replace 'val-erate' by 'va-lerate'.
L40 Replace 'prod-ucts' by 'pro-ducts'.
L43 Replace 'materi-als' by 'mate-rials'.
L49-L50 Replace 'Crop byproducts ... present a' by 'They are considered as a'.
L57-L58 Replace 'bulb-ous' by 'bul-bous'.
L63-L64 Replace 'al-lylsulfides' by 'allyl-sulfides'.
L71-L72 Replace 'prom-ising' by 'promi-sing'.
L75 Write in italics 'Ipomoea batatas'.
L75-L76 Replace 'glob-ally' by 'glo-bally'.
L90 Replace 'crude protein' by 'CP'.
L98-L99 Replace 'var-iables' by 'va-riables'.
L110-L111 Write 'in vitro' in italics.
L111 Replace 'in the sweet potato vines' by ' for the utilization of these three non-conventional feed ressources in ruminants nutrition'.
L113 Replace 'Materials and Experimental Design' by 'Experimental Design and Treatments'.
L116 Delete a space between '65º' and 'C'.
L116 Introduce the model of the dryer.
L117 Write 'in vitro' in italics.
L119 Replace 'information' by 'ingredient name' and 'six' by 'three'.
L119 Explain which were the treatments under study and how many samples were assigned to each treatment for running your fermentation trial.
Table 1: Provide information related to the roughages tested as how/when did you get them?, which was the process carried out to use them?, etc.
L125 Replace 'Ash' by 'ash'.
L134-L135 Replace 'fol-lows' by 'fo-llows'.
L140 Delete a space before 'The specific' and replace 'is' by 'are'.
L141-142 Add information related to the cows selected for collecting the rumen liquid (provide the following data: age, parity, days in milk, body weight, body condition score and dry matter intake) and diet used to feed them.
L143 Write 'ad libitum' in italics.
L144-L145 Replace 'vac-uum' by 'va-cuum' and introduce the model used.
L147 Write 'in vitro' in italics.
L149 Introduce the model of the equipment used for rumen fermentation.
L152 Delete a space between '39º' and 'C'.
L152 Add the protocol number got after the approval of the Ethical Committee for collection of the rumen samples from the cows. Specify also how many runs were conducted per each treatment and how many glass jar were used in total and how many of them were assigned to each treatment.
L160 Write 'in vitro' in italics.
L162 Replace 'fol-lowing' by 'fo-llowing'.
L167-L168 Replace 'as-sessed' by 'a-ssessed'.
L168-L169 Replace 'signif-icant' by 'signi-ficant'.
L169 Add the mathematical model used for running the statistical analysis and describe each of the factors under study.
L174 Replace 'higher Ash content' by 'the highest ash content'.
L176 Replace 'the highest 18.85%' by 'the highest value 18.85% found'.
Ll184 Delete 'of cotton straw' and replace 'also highest' by 'also the hihest'.
L185 Replace 'and lowest for garlic peel' by ', while the lowest for garlic peel'.
L191 Replace 'being highest' by 'being the highest' and 'and lowest' by 'while the lowest'.
L192 Replace 'The IVNDFD of sweet potato vine (72.56%) was also significantly higher (P<0.05) than' by 'The highest IVNDFD was also found in sweet potato vine (72.56%) than in'.
Table 5: Replace 'In vitro rumen fermentation ... of the three by-products' by 'In vitro rumen degradation rate, gas production and gas parameters of the three by-products'.
L202 Write 'in vitro' in italics and replace 'produc-tion' by 'produ-ction'.
L206 Write 'in vitro' in italics.
L213 Delete 'it produced'.
L242 Replace 'energy' by 'Energy'.
L269 Write 'in vitro' in italics.
L270 Write 'in vitro' in italics.
L276-L277 Replace 'microorgan-isms' by 'microorga-nisms'.
L280 Write 'in vitro' in italics.
L290-L291 Replace 'roughage' by 'roughages'.
L292 Replace 'helps maintain' by 'helps to maintain' and write 'in vitro' in italics.
L306-L307 Replace 'organ-ism' by 'orga-nism'.
L319-320 Replace 'ap-pears' by 'a-ppears'.
L322 Replace 'is needed' by 'is needed due to sweet potato vine seems to show also higher gas production than the other two by-products'.
L339-440 Review all the references mentioned herein. Cite them according to Fementation's instructions for authors.
Author Response
Comments:
L14 Write 'in vitro' in italics.
Reply: Revised.
L16 Replace 'Ash' by 'ash'.
Reply: Revised.
L17 Replace ', and the' by ', while the'.
Reply: Revised.
L18 Replace 'were highly' by 'were'.
Reply: Revised.
L19 Replace 'the other two feeds' by 'the others'.
Reply: Revised.
L21 Write 'in vitro' in italics.
Reply: Revised.
L25 Replace 'The sweet' by 'the sweet' and put 3 in subscript in 'NH3'.
Reply: Revised.
L28 Replace 'val-erate' by 'va-lerate'.
Reply: Revised.
L40 Replace 'prod-ucts' by 'pro-ducts'.
Reply: Revised.
L43 Replace 'materi-als' by 'mate-rials'.
Reply: Revised.
L49-L50 Replace 'Crop byproducts ... present a' by 'They are considered as a'.
Reply: Revised.
L57-L58 Replace 'bulb-ous' by 'bul-bous'.
Reply: Revised.
L63-L64 Replace 'al-lylsulfides' by 'allyl-sulfides'.
Reply: Revised.
L71-L72 Replace 'prom-ising' by 'promi-sing'.
Reply: Revised.
L75 Write in italics 'Ipomoea batatas'.
Reply: Revised.
L75-L76 Replace 'glob-ally' by 'glo-bally'.
Reply: Revised.
L90 Replace 'crude protein' by 'CP'.
Reply: Revised.
L98-L99 Replace 'var-iables' by 'va-riables'.
Reply: Revised.
L110-L111 Write 'in vitro' in italics.
Reply: Revised.
L111 Replace 'in the sweet potato vines' by ' for the utilization of these three non-conventional feed ressources in ruminants nutrition'.
Reply: Revised.
L113 Replace 'Materials and Experimental Design' by 'Experimental Design and Treatments'.
Reply: Revised.
L116 Delete a space between '65º' and 'C'.
Reply: Revised.
L116 Introduce the model of the dryer.
Reply: Revised.
L117 Write 'in vitro' in italics.
Reply: Revised.
L119 Replace 'information' by 'ingredient name' and 'six' by 'three'.
Reply: Revised.
L119 Explain which were the treatments under study and how many samples were assigned to each treatment for running your fermentation trial.
Reply: Revised. Garlic peel, sweet potato vine and cotton straw were used as the substrates for chemical composition analysis and in vitro rumen incubation. All the substrates were run in triplicate.
Table 1: Provide information related to the roughages tested as how/when did you get them?, which was the process carried out to use them?, etc.
Reply: Revised. The information has been added. Please see Line 115-121.
L125 Replace 'Ash' by 'ash'.
Reply: Revised.
L134-L135 Replace 'fol-lows' by 'fo-llows'.
Reply: Revised.
L140 Delete a space before 'The specific' and replace 'is' by 'are'.
Reply: Revised.
L141-142 Add information related to the cows selected for collecting the rumen liquid (provide the following data: age, parity, days in milk, body weight, body condition score and dry matter intake) and diet used to feed them.
Reply: Revised. The information has been added. Please see Line 156-166.
L143 Write 'ad libitum' in italics.
Reply: Revised.
L144-L145 Replace 'vac-uum' by 'va-cuum' and introduce the model used.
Reply: Revised.
L147 Write 'in vitro' in italics.
Reply: Revised.
L149 Introduce the model of the equipment used for rumen fermentation.
Reply: Revised. Please see Line 171-172.
L152 Delete a space between '39º' and 'C'.
Reply: Revised.
L152 Add the protocol number got after the approval of the Ethical Committee for collection of the rumen samples from the cows. Specify also how many runs were conducted per each treatment and how many glass jar were used in total and how many of them were assigned to each treatment.
Reply: The information of ethics approval has been added, please see Line 161-163. The description of the experimental treatments and replicates were added. Please see Line 156-158.
L160 Write 'in vitro' in italics.
Reply: Revised.
L162 Replace 'fol-lowing' by 'fo-llowing'.
Reply: Revised.
L167-L168 Replace 'as-sessed' by 'a-ssessed'.
Reply: Revised.
L168-L169 Replace 'signif-icant' by 'signi-ficant'.
Reply: Revised.
L169 Add the mathematical model used for running the statistical analysis and describe each of the factors under study.
Reply: The description of the mathematical model and factors were added. Please see Line 192-197.
L174 Replace 'higher Ash content' by 'the highest ash content'.
Reply: Revised.
L176 Replace 'the highest 18.85%' by 'the highest value 18.85% found'.
Reply: Revised.
Ll184 Delete 'of cotton straw' and replace 'also highest' by 'also the hihest'.
Reply: Revised.
L185 Replace 'and lowest for garlic peel' by ', while the lowest for garlic peel'.
Reply: Revised.
L191 Replace 'being highest' by 'being the highest' and 'and lowest' by 'while the lowest'.
Reply: Revised.
L192 Replace 'The IVNDFD of sweet potato vine (72.56%) was also significantly higher (P<0.05) than' by 'The highest IVNDFD was also found in sweet potato vine (72.56%) than in'.
Reply: Revised.
Table 5: Replace 'In vitro rumen fermentation ... of the three by-products' by 'In vitro rumen degradation rate, gas production and gas parameters of the three by-products'.
Reply: Revised.
L202 Write 'in vitro' in italics and replace 'produc-tion' by 'produ-ction'.
Reply: Revised.
L206 Write 'in vitro' in italics.
Reply: Revised.
L213 Delete 'it produced'.
Reply: Revised.
L242 Replace 'energy' by 'Energy'.
Reply: Revised.
L269 Write 'in vitro' in italics.
Reply: Revised.
L270 Write 'in vitro' in italics.
Reply: Revised.
L276-L277 Replace 'microorgan-isms' by 'microorga-nisms'.
Reply: Revised.
L280 Write 'in vitro' in italics.
Reply: Revised.
L290-L291 Replace 'roughage' by 'roughages'.
Reply: Revised.
L292 Replace 'helps maintain' by 'helps to maintain' and write 'in vitro' in italics.
Reply: Revised.
L306-L307 Replace 'organ-ism' by 'orga-nism'.
Reply: Revised.
L319-320 Replace 'ap-pears' by 'a-ppears'.
Reply: Revised.
L322 Replace 'is needed' by 'is needed due to sweet potato vine seems to show also higher gas production than the other two by-products'.
Reply: Revised.
L339-440 Review all the references mentioned herein. Cite them according to Fementation's instructions for authors.
Reply: We have revised all the references. Please see Line 382-557.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Comments and Suggestions for Authors
My comments has been well explained and revised, and I have no further comments.
Comments on the Quality of English Language
Minor editing of English language required.
Reviewer 2 Report
Comments and Suggestions for Authors
Dear Authors,
Your manuscript entitled "Assessment of the Nutrient Value and In Vitro Rumen Fermentation Characteristics of Garlic Peel, Sweet Potato Vine and Cotton Straw" might be now considered suitable for publication in Ruminants in current form. Please, see below only a suggestion to be applied by you before it is published. Congratulations to all of you for this achievement!
L263-L264 Replace 'Leymus chinensis' by 'Leymus chinensis (Trin.) Tzvelev'.
Yours sincerely,
Reviewer.
