Haemonchosis Control in Sheep with Duddingtonia flagrans Fungi: Evaluation of the First Commercial Product in Brazil

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The study provides data on the efficacy of the commercial preparation Bioverm®, containing nematophagous fungi, as an alternative and supplement to chemical control of gastrointestinal nematodes in sheep. Given the increasing resistance of gastrointestinal nematodes to standard dewormers, the choice of topic is relevant and I welcome it. However, I feel that the manuscript needs some corrections to improve it and make it more understandable for readers. The authors can find my suggestions below.

The proposed title is attractive, but it is quite general. If it remains as it is, more information on the biological control of helminths should be added in the introduction.

The study is based on the evaluation of three indicators. I propose to call  the second of them "FAMACHA" instead of "SCORE", as this is more correct from a terminological point of view. The name of the indicator should be consistent throughout the manuscript.

Please formulate the purpose of the study given the terminology of the three indicators assessed (lines 54-57).

FAMACHA is a system for assessment of the clinical anaemia in animals with Haemonchus contortus infection. Therefore, please describe in the “Materials and methods” section how the taxonomic composition of gastrointestinal nematodes in the herd was investigated and describe in the “Results” section what was found – which nematodes were identified, what was the prevalence of Haemonchus, etc.

Author Response

First, we express our thanks to the reviewer for the time invested and the suggestions provided. These were undoubtedly fundamental in enriching this manuscript, and all recommendations that could be implemented were addressed. Where we were unable to incorporate them, we have clearly justified the reasons.

 

Comments 1: The proposed title is attractive, but it is quite general. If it remains as it is, more information on the biological control of helminths should be added in the introduction.

Response 1: We have revised the title to better focus on the subject: "Haemonchosis Control in Sheep with Duddingtonia flagrans Fungi: Evaluation of the First Commercial Product in Brazil"

 

Comments 2: The study is based on the evaluation of three indicators. I propose to call  the second of them "FAMACHA" instead of "SCORE", as this is more correct from a terminological point of view. The name of the indicator should be consistent throughout the manuscript.

Please formulate the purpose of the study given the terminology of the three indicators assessed (lines 54-57).

Response 2: We appreciate and agree with the suggestion to replace SCORE with FAMACHA. The necessary changes have been made.

 

Comments 3: FAMACHA is a system for assessment of the clinical anaemia in animals with Haemonchus contortus infection. Therefore, please describe in the “Materials and methods” section how the taxonomic composition of gastrointestinal nematodes in the herd was investigated and describe in the “Results” section what was found – which nematodes were identified, what was the prevalence of Haemonchus, etc.

Response 3: We understand and agree with the reviewer’s recommendation. However, unfortunately, it will not be possible to address this aspect. Nevertheless, we have changed the submission type from "Article" to "Communication."

In this study, conducted on a commercial farm (not in an experimental setting), we did not identify the parasite species but instead focused solely on quantifying the egg counts. The EPG results are therefore quantitative and can only suggest the possible parasite species. Confirming the specific species requires specialized parasitologists using coproculture techniques.

Although FAMACHA only detects Haemonchus (the primary challenge in sheep and goat farming in Brazil), it is well-established that Duddingtonia flagrans is effective against helminths in general (and not solely Haemonchus).

We sincerely appreciate the reviewer’s recommendation, which has been thoroughly noted and will be considered in future studies.

Reviewer 2 Report

Comments and Suggestions for Authors

I congratulate the authors for the work. Biological control is a very relevant topic for animal health and production.

Despite the importance of the topic, I suggest an in-depth review of the manuscript, so that it can be considered for publication:

- Title: it is an interesting title, which arouses curiosity for reading the work. However, it is more appropriate for a review manuscript

- I suggest that the keyword “Arthrobotrys flagrans” be replaced

- Some gaps are observed in the description of the methodology:

• Was feces collected by a veterinarian?
• What is the average age of the animals?
• Regarding the food management systems used during the experimental period: did all the animals receive the same nutritional management (although at different times)?
• Regarding the treatment with Bioverme®: how was it performed? Following the product dosage recommendations? Was it given daily?
• Regarding the EPG: were the analyses individual? How were values ​​below 50 obtained? According to the reference cited in the methodology, for small ruminants the correct calculation would be the multiplication x 100 for each egg visualized

- Why is “A. flagrans” mentioned in the figure caption? In this section, it should be changed to Duddingtonia flagrans (without abbreviating) and the information (Bioverme®) should be added

- Statistical analyses: it would be important to present the coefficient of determination.

Author Response

We would like to begin by thanking the reviewer for the time dedicated and the valuable contributions provided. Without a doubt, these were essential for improving this manuscript, and all feasible suggestions have been implemented. In cases where this was not possible, we have included a justification explaining the reason.

Comments 1: Title: it is an interesting title, which arouses curiosity for reading the work. However, it is more appropriate for a review manuscript

Response 1: We have revised the title to better focus on the subject: "Haemonchosis Control in Sheep with Duddingtonia flagrans Fungi: Evaluation of the First Commercial Product in Brazil"

 

Comments 2: I suggest that the keyword “Arthrobotrys flagrans” be replaced

Response 2: Our goal with the keywords is to ensure a greater number of people find the article. Therefore, we included Arthrobotrys flagrans because some recent studies have suggested changing Duddingtonia to Arthrobotrys. We maintained the nomenclature Duddingtonia flagrans since it is used in the product registration, and most researchers continue to use this name. However, we decided to keep Arthrobotrys flagrans in the keywords to help locate the article if searched for under this terminology.

 

Comments 3: 

Some gaps are observed in the description of the methodology:

Was feces collected by a veterinarian?
What is the average age of the animals?
Regarding the food management systems used during the experimental period: did all the animals receive the same nutritional management (although at different times)?
Regarding the treatment with Bioverme®: how was it performed? Following the product dosage recommendations? Was it given daily?
Regarding the EPG: were the analyses individual? How were values ​​below 50 obtained? According to the reference cited in the methodology, for small ruminants the correct calculation would be the multiplication x 100 for each egg visualized
- Why is “A. flagrans” mentioned in the figure caption? In this section, it should be changed to Duddingtonia flagrans (without abbreviating) and the information (Bioverme®) should be added

- Statistical analyses: it would be important to present the coefficient of determination.

Response 3: 

All the necessary information has been supplemented and is now included in the methodology section. We appreciate the reviewer’s attention to these points, which were indeed critical and required inclusion.

Regarding the EPG: the multiplication factor is x50 when 4g of feces are used. This information has now been added.

 

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The authors have responded to my questions and suggestions. I agree with the corrections to the text, the change of title and the type of publication and believe that the manuscript has been significantly improved in this form.

Author Response

Once again, we appreciate the attention and time this reviewer devoted to our manuscript.

Reviewer 2 Report

Comments and Suggestions for Authors

Some points to improve:

Material and Methods:
*Line 77: "ad libitum" - italics
*Lines 90-91: please translate to english the sentence

Author Response

Comments:Material and Methods:
*Line 77: "ad libitum" - italics
*Lines 90-91: please translate to english the sentence

Response: We appreciate the attention to both details, both corrected, and the time this reviewer dedicated to our manuscript.