Factors Influencing the Setting of Automatic Teat Cup Removal at the End of Machine Milking in Dairy Cows—An Overview

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

paper, titled "Factors influencing the setting of automatic teat cup removal at the end of machine milking in dairy cows Technical report", addresses an important and timely topic. I found the subject matter of the article fascinating and read the manuscript with great interest. The paper aligns well with the scope of the journal. However, I believe that in its current form, it has several shortcomings.

Simple Summary

is quite detailed, almost replicating parts of the abstract. While it gives a good overview of the practical recommendations, it could be more concise and perhaps highlight the "why" behind these recommendations more clearly for a general audience. For example, stating that "milking time is an important aspect of dairy farming" is a bit of an understatement, perhaps elaborating why it's important would be better. Also, the repetition of the recommended ATCR values here and in the abstract and conclusions feels a bit much.

phrase "Increased milk production per cow has led to longer milking times in recent decades" could be slightly rephrased for conciseness, perhaps "Rising milk production per cow has extended milking times in recent decades." The concluding sentence of the summary, "However, if the milking machine uses a higher vacuum, it is possible to program a higher ATCR at a milk flow of up to 0.5 kg/min⁻¹" could be a bit clearer on why a higher vacuum allows for a higher ATCR.

Abstract

does a reasonable job outlining the problem of overmilking and the importance of ATCR. However, the stated "aim of this study was to describe the factors influencing automatic teat cup removal (ATCR) at the end of mechanical milking and to demonstrate its importance for udder health, milk production, and milk quality" is more of a review objective rather than a specific research aim. It would be strengthened by clearly stating if any original data or novel analyses were conducted to support the conclusions, as it currently seems to be a synthesis of existing studies. The vacuum levels are mentioned, but it's not immediately clear if these were tested in this study or are just generalized observations. The conclusion section of the abstract also feels a bit too long, almost a mini-conclusion section for the entire paper, and it also repeats the recommended ATCR values again.

Check for consistency in the use of units; for instance, "kg/min" and "kg·min⁻¹" are both used. While technically the same, sticking to one format would be cleaner. The sentence "The optimum ATCR settings are often defined by the milk flow rate at which the cluster detaches from the udder" might benefit from slightly stronger phrasing, such as "Optimal ATCR settings are typically defined by the milk flow rate..."

Introduction

provides a good historical context for ATCR. It effectively sets up the debate surrounding optimal ATCR settings, acknowledging conflicting views on emptying the udder completely versus reducing overmilking. However, I believe the paper would benefit from a broader initial context. It would be highly valuable if the authors could include a more general introduction to Precision Livestock Farming (PLF), discussing its overall significance and benefits in modern dairy farming. Furthermore, an overview of various technologies used in PLF, beyond just Automatic Milking Systems (AMS), would be beneficial. This could encompass other relevant tools such as collars (10.3390/ani15030458), ear tags (10.3389/fanim.2025.1547395), cameras (10.3168/jds.2008-1218 and 10.3168/jds.2020-18867), scales ( 10.3168/jds.2020-19912), urine analysis (10.29261/pakvetj/2020.067) and autofeeders (10.3168/jds.2020-19951), illustrating how ATCR fits within this wider technological landscape. Finally, the final sentence stating the objective of the study is, again, phrased as a descriptive review rather than an investigation. If this is indeed a review paper, it should be explicitly stated from the beginning. If it's a technical report, there needs to be a clearer statement of the specific technical contribution or new insights.

the second paragraph, the sentence "Mechanical milking has undergone continuous innovation since its introduction in the early 20th century" could be more precise with "early 20th century" or perhaps "since its widespread adoption in the early 20th century." The phrasing "reducing the milking process" is a bit awkward; "reducing the milking duration" or "optimizing the milking process" might fit better.

2. Importance of automatic teat cup removal

discusses the importance of ATCR for udder health, milk yield, and quality, which is central to the paper's theme. The inclusion of Table 1 showing parameters from a commercial dairy farm using MultiLactor is a nice touch, but its specific relevance to this technical report's contribution should be elaborated. Is this an example from a system the author is associated with? If so, it needs to be clearly stated and any potential conflicts of interest explicitly declared. The figures are quite useful in illustrating the points, but Figure 1 could use a bit more explanation in the text regarding what "a" and "b" signify statistically beyond the caption. Also, there's a reference to "Figure 2" well before it appears in the text, which is a bit jarring.

caption for Figure 1 mentions "a" and "b" without immediately clear definitions within the caption itself; perhaps explicitly state "where 'a' represents X and 'b' represents Y" for instant clarity. In the paragraph referring to Figure 2, it is mentioned before Figure 2 actually appears, which could confuse the reader. Consider moving the text referencing Figure 2 to follow its appearance.

3. Factors influencing automatic teat cup removal

• 3.1. Automatic teat cup removal and degree of udder emptying: makes strong points about the impact of incomplete milking on milk synthesis and udder health. Figure 2 is valuable, though the legend for the lines (solid vs. dashed) could be a little clearer in the main text, not just the caption. The discussion of "blind milking" is good, but it might be helpful to briefly define it earlier for readers less familiar with the term. The argument about weighing potential milk loss against reduced milking time is a practical and relevant point. The sentence "Milk left in the udder, also called residual milk, has been shown to reduce milk synthesis during the subsequent milking" could be slightly rephrased to avoid the passive voice, for instance, "Residual milk in the udder has been shown to reduce milk synthesis..." The term "blind milking" is used several times; a very brief, perhaps parenthetical, explanation upon its first use would be helpful for non-specialist readers.
• 3.2. Automatic teat cup removal and udder health: nicely elaborates on the health implications of ATCR settings, connecting it to mastitis risk and teat condition. The discussion about forequarters and hindquarters having different milk yields and the challenge this poses for uniform ATCR is interesting and important. Table 2 is particularly informative, showing actual data on milking parameters. However, the interpretation of the table "the parameters studied provided better results in terms of milk quality and udder health at an ACTR of 0.2 kg.min¹ than at an ATCR of 0.4 kg.min¹" seems to oversimplify the results, as SCC and fat yield were "NS" (not significant). This needs to be rephrased for accuracy, acknowledging where no significant difference was found. Also, the reference to "ACTR" instead of "ATCR" in that sentence is a small but noticeable typo. Figure 3 illustrating hyperkeratosis is very useful for practical application. In the discussion around Table 2, the phrasing "the parameters studied provided better results in terms of milk quality and udder health at an ACTR of 0.2 kg.min⁻¹ than at an ATCR of 0.4 kg.min⁻¹" should be re-evaluated as some of the differences in Table 2 are noted as "NS" (not significant). This overstatement could be corrected to accurately reflect the statistical findings. Also, there's a small typo "ACTR" which should be "ATCR."
• 3.3. Automatic teat cup removal and daily milking frequency: correctly identifies milking frequency as a key factor. The distinction between twice- and thrice-daily milking recommendations for ATCR is well-made. It's interesting to note the reference to "modern dairy cow breeds (European breeds)"; this could be expanded upon slightly, perhaps mentioning if other breeds might have different optimal settings.
• 3.4. Automatic teat cup removal and lactation number: discusses the influence of lactation number. The statement "Thus, it was found that parity has no influence on milk yield or milking time" directly contradicts the initial sentence of the subsection which states "milk yield and milking time were higher in early lactation... than in first lactation". This needs clarification or reconciliation. In the discussion around Table 2, the phrasing "the parameters studied provided better results in terms of milk quality and udder health at an ACTR of 0.2 kg.min⁻¹ than at an ATCR of 0.4 kg.min⁻¹" should be re-evaluated as some of the differences in Table 2 are noted as "NS" (not significant). This overstatement could be corrected to accurately reflect the statistical findings. Also, there's a small typo "ACTR" which should be "ATCR."
• 3.5. Automatic teat cup removal and stage of lactation: a brief section but makes a clear point about early versus late lactation.
• 3.6. Uncontrolled change in the setting for automatic teat cup removal: This section brings up an important practical concern about farmers manually overriding ATCR settings. The description of teat damage due to "blind milking" and high negative pressure is vivid and well-explained. The discussion of hyperkeratosis in this context is also very relevant.

I recommend that the authors consider discussing the dissemination of their findings to the broader public through modern platforms like social media. This proactive approach is crucial for counteracting misinformation prevalent in animal science and fostering wider understanding.

In a parallel vein, a study focused on utilizing Instagram illustrates how social media can serve as an effective tool (10.3168/jds.2024-25347). This study underscores the power of social media in conveying complex topics, such as the optimal settings for automatic teat cup removal and their impact on udder health and milk quality, to a broad audience. Such initiatives complement the role of influencers in accurate dairy farming communication by providing tangible examples of how digital platforms can foster community engagement and awareness in specialized areas.

4. Conclusions

summarize the key recommendations effectively, especially the specific ATCR settings based on vacuum levels and milking frequency. However, like the abstract, the conclusions still sound more like a summary of general findings rather than specific outcomes of this technical report. It reinforces the earlier observation that the paper needs to clarify its scope and unique contribution. The mention of "cow grouping" as a factor in the conclusion wasn't explicitly discussed in the main body, so it feels a little out of place here. It might be better to either integrate it into the discussion or remove it from the conclusions

mentions "cow grouping" as a factor, but this topic was not explicitly detailed in the main body of the report. If it's a relevant factor, a brief discussion should be included earlier, or this mention might be removed from the conclusions to avoid introducing new information. The overall tone of the conclusion is quite informative, but some sentences, such as "Udder health is the most important factor in the success of dairy farms," could be rephrased to flow more smoothly within the scientific context.

 

Author Response

Comments 1: Comments and Suggestions for Authors

Paper, titled "Factors influencing the setting of automatic teat cup removal at the end of machine milking in dairy cows Technical report", addresses an important and timely topic. I found the subject matter of the article fascinating and read the manuscript with great interest. The paper aligns well with the scope of the journal. However, I believe that in its current form, it has several shortcomings.

Response 1: Thank you for your comments, which are very important for the manuscript.

 

Comments 2: Simple Summary

(1): is quite detailed, almost replicating parts of the abstract. While it gives a good overview of the practical recommendations, it could be more concise and perhaps highlight the "why" behind these recommendations more clearly for a general audience. For example, stating that "milking time is an important aspect of dairy farming" is a bit of an understatement, perhaps elaborating why it's important would be better. Also, the repetition of the recommended ATCR values here and in the abstract and conclusions feels a bit much.

(2): phrase "Increased milk production per cow has led to longer milking times in recent decades" could be slightly rephrased for conciseness, perhaps "Rising milk production per cow has extended milking times in recent decades." The concluding sentence of the summary, "However, if the milking machine uses a higher vacuum, it is possible to program a higher ATCR at a milk flow of up to 0.5 kg/min⁻¹" could be a bit clearer on why a higher vacuum allows for a higher ATCR.

Response 2: (1): Thank you for your comments. Since this simple summary is intended to contain some results, some results should be presented in a similar way to the results presented in the Abstract. However, I have changed a few things in the simple summary. See the edited manuscript.  (2): It is done. You can see the change in the text.

 

Comments 3: Abstract

(1): does a reasonable job outlining the problem of overmilking and the importance of ATCR. However, the stated "aim of this study was to describe the factors influencing automatic teat cup removal (ATCR) at the end of mechanical milking and to demonstrate its importance for udder health, milk production, and milk quality" is more of a review objective rather than a specific research aim. It would be strengthened by clearly stating if any original data or novel analyses were conducted to support the conclusions, as it currently seems to be a synthesis of existing studies. (2): The vacuum levels are mentioned, but it's not immediately clear if these were tested in this study or are just generalized observations. (3): The conclusion section of the abstract also feels a bit too long, almost a mini-conclusion section for the entire paper, and it also repeats the recommended ATCR values again.

(4): Check for consistency in the use of units; for instance, "kg/min" and "kg·min⁻¹" are both used. While technically the same, sticking to one format would be cleaner. (5): The sentence "The optimum ATCR settings are often defined by the milk flow rate at which the cluster detaches from the udder" might benefit from slightly stronger phrasing, such as "Optimal ATCR settings are typically defined by the milk flow rate..."

Response 3:

(1): Thank you for your comments on the abstract. What you wrote is correct: "This study is more of a review objective rather than a specific research aim." It is an overview of the problem through the collection and review of a literature study. Therefore, the subject of the manuscript was changed from “Technical report” to “Overview”. See the edited manuscript. (2): These vacuum values were determined by the milking machine manufacturer and we have taken this information from published studies. (3): You are right, the conclusion is too long. It was shortened. See the edited manuscript. (4): It is done for the use of one unit in this study. (5): It is done. See the revised manuscript.

 

Comments 4: Introduction

(1): provides a good historical context for ATCR. It effectively sets up the debate surrounding optimal ATCR settings, acknowledging conflicting views on emptying the udder completely versus reducing overmilking. However, I believe the paper would benefit from a broader initial context. It would be highly valuable if the authors could include a more general introduction to Precision Livestock Farming (PLF), discussing its overall significance and benefits in modern dairy farming. (2) Furthermore, an overview of various technologies used in PLF, beyond just Automatic Milking Systems (AMS), would be beneficial. This could encompass other relevant tools such as collars (10.3390/ani15030458), ear tags (10.3389/fanim.2025.1547395), cameras (10.3168/jds.2008-1218 and 10.3168/jds.2020-18867), scales ( 10.3168/jds.2020-19912), urine analysis (10.29261/pakvetj/2020.067) and autofeeders (10.3168/jds.2020-19951), illustrating how ATCR fits within this wider technological landscape. (3): Finally, the final sentence stating the objective of the study is, again, phrased as a descriptive review rather than an investigation. If this is indeed a review paper, it should be explicitly stated from the beginning. If it's a technical report, there needs to be a clearer statement of the specific technical contribution or new insights.

(4): the second paragraph, the sentence "Mechanical milking has undergone continuous innovation since its introduction in the early 20th century" could be more precise with "early 20th century" or perhaps "since its widespread adoption in the early 20th century." The phrasing "reducing the milking process" is a bit awkward; "reducing the milking duration" or "optimizing the milking process" might fit better.

Response 4:

Thank you for your comments in this section. (1): We focused on the factors that influence automatic teat cup removal at the end of machine milking of dairy cows to achieve a practical ideal value for the ATCR. It is not possible to describe all modern technical devices used on dairy farms in one scientific paper.  (2): The goal of this study is to provide a clear overview of the ATCR at the end of mechanical milking. Therefore, we focused on this topic. The use of modern and advanced technologies on dairy farms is crucial but was not addressed in this study because it is not our objective. (3): Yes, you are right. This is an overview presentation. It was corrected in the manuscript. (4): Yes, that is true. This process shortens milking time and thus improves milking efficiency. See the edited manuscript.

 

Comments 5: Importance of automatic teat cup removal

(1): discusses the importance of ATCR for udder health, milk yield, and quality, which is central to the paper's theme. (2): The inclusion of Table 1 showing parameters from a commercial dairy farm using MultiLactor is a nice touch, but its specific relevance to this technical report's contribution should be elaborated. Is this an example from a system the author is associated with? If so, it needs to be clearly stated and any potential conflicts of interest explicitly declared. (3): The figures are quite useful in illustrating the points, but Figure 1 could use a bit more explanation in the text regarding what "a" and "b" signify statistically beyond the caption. (4): Also, there's a reference to "Figure 2" well before it appears in the text, which is a bit jarring.

(5): caption for Figure 1 mentions "a" and "b" without immediately clear definitions within the caption itself; perhaps explicitly state "where 'a' represents X and 'b' represents Y" for instant clarity. (6): In the paragraph referring to Figure 2, it is mentioned before Figure 2 actually appears, which could confuse the reader. Consider moving the text referencing Figure 2 to follow its appearance.

Response 5:

(1): Thank you for your comment in this part. (2): It is always a good idea to include tables and figures in a scientific paper, as they provide a simple overview of the work. In this study, the tables and figures were taken from previously published international research papers. Therefore, there is no conflict in this regard. (3): Yes, that is right. That was done in the edited manuscript. (4): It is done. See the revised manuscript. (5): It is done. See the revised manuscript. (6): It is done. See the revised manuscript.

 

Comments 6: Factors influencing automatic teat cup removal

Automatic teat cup removal and degree of udder emptying: (1): makes strong points about the impact of incomplete milking on milk synthesis and udder health. Figure 2 is valuable, though the legend for the lines (solid vs. dashed) could be a little clearer in the main text, not just the caption. (2): The discussion of "blind milking" is good, but it might be helpful to briefly define it earlier for readers less familiar with the term. (3): The argument about weighing potential milk loss against reduced milking time is a practical and relevant point. (4): The sentence "Milk left in the udder, also called residual milk, has been shown to reduce milk synthesis during the subsequent milking" could be slightly rephrased to avoid the passive voice, for instance, "Residual milk in the udder has been shown to reduce milk synthesis. (5): " The term "blind milking" is used several times; a very brief, perhaps parenthetical, explanation upon its first use would be helpful for non-specialist readers.

Response 6:

Thank you for your comments in this chapter. (1): Thank you for your comment. (2): Thank you for this comment. The term "blind milking" was provided as a definition in the text. (3): Yes, that's right, thanks for this comment. (4): It is done. See the revised manuscript. (5): The term "blind milking" was provided as a definition in the text.

 

Comments 7: Automatic teat cup removal and udder health: (1): nicely elaborates on the health implications of ATCR settings, connecting it to mastitis risk and teat condition. The discussion about forequarters and hindquarters having different milk yields and the challenge this poses for uniform ATCR is interesting and important. (2): Table 2 is particularly informative, showing actual data on milking parameters. However, the interpretation of the table "the parameters studied provided better results in terms of milk quality and udder health at an ACTR of 0.2 kg.min¹ than at an ATCR of 0.4 kg.min¹" seems to oversimplify the results, as SCC and fat yield were "NS" (not significant). (3): This needs to be rephrased for accuracy, acknowledging where no significant difference was found. (4): Also, the reference to "ACTR" instead of "ATCR" in that sentence is a small but noticeable typo. (5): Figure 3 illustrating hyperkeratosis is very useful for practical application. (6): In the discussion around Table 2, the phrasing "the parameters studied provided better results in terms of milk quality and udder health at an ACTR of 0.2 kg.min⁻¹ than at an ATCR of 0.4 kg.min⁻¹" should be re-evaluated as some of the differences in Table 2 are noted as "NS" (not significant). This overstatement could be corrected to accurately reflect the statistical findings. (7): Also, there's a small typo "ACTR" which should be "ATCR."

Response 7: Thank you for your comments in this part. (1): Yes, that is very interesting. (2): Yes, that is correct, but although the ATCR is narrowly between 0.2 kg.min^-1 and 0.4 kg.min^-1, differences can be seen in milking time, post-milking strip yield and daily milk protein yield. (3): Yes, that is right, see the edited manuscript. (4): Yes, it has been corrected. (5): Yes, it is very important. (6): Yes, it is done in the edited manuscript. (7): Yes, it has been corrected.

 

Comments 8: Automatic teat cup removal and daily milking frequency: (1): correctly identifies milking frequency as a key factor. (2): The distinction between twice- and thrice-daily milking recommendations for ATCR is well-made. (3): It is interesting to note the reference to "modern dairy cow breeds (European breeds)"; this could be expanded upon slightly, perhaps mentioning if other breeds might have different optimal settings.

Response 8: Thank you for your comment. (1): Yes, sure. (2): Thank you very much for this comment. (3): It is done in the edited manuscript.

 

Comments 9: Automatic teat cup removal and lactation number:  discusses the influence of lactation number. (1): The statement "Thus, it was found that parity has no influence on milk yield or milking time" directly contradicts the initial sentence of the subsection which states "milk yield and milking time were higher in early lactation... than in first lactation". This needs clarification or reconciliation. (2): In the discussion around Table 2, the phrasing "the parameters studied provided better results in terms of milk quality and udder health at an ACTR of 0.2 kg.min⁻¹ than at an ATCR of 0.4 kg.min⁻¹" should be re-evaluated as some of the differences in Table 2 are noted as "NS" (not significant). This overstatement could be corrected to accurately reflect the statistical findings. (3): Also, there's a small typo "ACTR" which should be "ATCR."

Response 9: Thank you for your comment. (1): Yes, you are right, this section has been restructured. See the revised manuscript. (2): Yes, it is done in the edited manuscript. (3): Yes, it has been corrected

 

Comment 10: Automatic teat cup removal and stage of lactation: a brief section but makes a clear point about early versus late lactation.

Response 10: Thank you for your comment.

 

Comments 11: Uncontrolled change in the setting for automatic teat cup removal: (1): This section brings up an important practical concern about farmers manually overriding ATCR settings. The description of teat damage due to "blind milking" and high negative pressure is vivid and well-explained. The discussion of hyperkeratosis in this context is also very relevant.

(2): I recommend that the authors consider discussing the dissemination of their findings to the broader public through modern platforms like social media. This proactive approach is crucial for counteracting misinformation prevalent in animal science and fostering wider understanding.

(3): In a parallel vein, a study focused on utilizing Instagram illustrates how social media can serve as an effective tool (10.3168/jds.2024-25347). This study underscores the power of social media in conveying complex topics, such as the optimal settings for automatic teat cup removal and their impact on udder health and milk quality, to a broad audience. Such initiatives complement the role of influencers in accurate dairy farming communication by providing tangible examples of how digital platforms can foster community engagement and awareness in specialized areas.

Response 11: (1): Thank you for your comment. (2): We would appreciate your recommendation to publish such scientific information on social media. (3): Yes, social media has a tremendous impact on people all over the world.

 

Comments 12: Conclusions

(1): summarize the key recommendations effectively, especially the specific ATCR settings based on vacuum levels and milking frequency. However, like the abstract, the conclusions still sound more like a summary of general findings rather than specific outcomes of this technical report. It reinforces the earlier observation that the paper needs to clarify its scope and unique contribution. (2): The mention of "cow grouping" as a factor in the conclusion wasn't explicitly discussed in the main body, so it feels a little out of place here. It might be better to either integrate it into the discussion or remove it from the conclusions.

mentions "cow grouping" as a factor, but this topic was not explicitly detailed in the main body of the report. If it's a relevant factor, a brief discussion should be included earlier, or this mention might be removed from the conclusions to avoid introducing new information. (3): The overall tone of the conclusion is quite informative, but some sentences, such as "Udder health is the most important factor in the success of dairy farms," could be rephrased to flow more smoothly within the scientific context.

Response 12: (1): Thank you for your comment. (2): You are right, this conclusion has been removed. (3): This comment has been considered, see the revised manuscript.

Reviewer 2 Report

Comments and Suggestions for Authors

Dear author and editor, this work is well-designed, organized, and easy to read. I have some suggestions.

Lines 101-104: As a suggestion, this paragraph should be placed before Table 1, avoiding the phrase "above-mentioned good results."
Lines 199-200: "It was observed that there was a significant difference in milk yield between forequarters and hindquarters, and the difference was approximately 1 kg of milk." In this study, which quarter produces more?
Lines 278-285: Suggestion: Move this paragraph related to Table 2 before it.
Points 3.3 and 3.4: I would like more details on the studies cited in these points or additional studies.

Author Response

Comments and Suggestions for Authors

Dear author and editor, this work is well-designed, organized, and easy to read. I have some suggestions.

Comment 1: Lines 101-104: As a suggestion, this paragraph should be placed before Table 1, avoiding the phrase "above-mentioned good results."

Response 1: Thank you for your comment. It is done, see the edited manuscript.

Comment 2: Lines 199-200: "It was observed that there was a significant difference in milk yield between forequarters and hindquarters, and the difference was approximately 1 kg of milk." In this study, which quarter produces more?

Response 2: Thank you for your comment. It is done, see the edited manuscript.

Comment 3: Lines 278-285: Suggestion: Move this paragraph related to Table 2 before it.

Responsr 3: Thank you for your comment. It is done, see the edited manuscript.

Comment 4: Points 3.3 and 3.4: I would like more details on the studies cited in these points or additional studies.

Response 4: Unfortunately, there are very few studies on these two factors “automatic teat cup removal and lactation number and automatic teat cup removal and lactation stage” and we would like to investigate these factors in more detail in the future.

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

the paper is fine