Prevalence and Diversity of Gastrointestinal Parasites and Tick Species in Communal Feedlots Compared to Rural Free-Grazing Cattle in the Eastern Cape Province, South Africa

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This article is an epidemiologic survey. The authors compared the prevalence, intensity and diversity of gastrointestinal parasites and tick species in cattle in rural communal grazing systems and communal feedlot systems in the Eastern Cape Province of South Africa. Materials, methods and results are easy to understand. This is a competent article on epidemiologic investigation.

Author Response

Reviewer Comment:
This article is an epidemiologic survey. The authors compared the prevalence, intensity and diversity of gastrointestinal parasites and tick species in cattle in rural communal grazing systems and communal feedlot systems in the Eastern Cape Province of South Africa. Materials, methods and results are easy to understand. This is a competent article on epidemiologic investigation.

Author Response:
We sincerely thank the reviewer for the positive and encouraging feedback. We are pleased that the study’s objectives, methodology, and results were found to be clearly presented and appropriate for an epidemiologic investigation. We appreciate the acknowledgement of the article’s competence and clarity, and we are committed to maintaining this standard throughout the final revision.

Reviewer 2 Report

Comments and Suggestions for Authors

Dear authors, congratulations on your epidemiological work. Here are some suggestions:

- In the keywords, I suggest not using the terms “Eastern Cape” and “South Africa”,

- On line 41, explain what “draught powe” means to make the text easier to understand.

- In item 2.4.1, the references of the parasitological methods used are not identified.

- What was considered the most recent time for deworming in item 3.4?

Author Response

1. Reviewer: In the keywords, I suggest not using the terms “Eastern Cape” and “South Africa”.
Response:
Thank you for this valuable suggestion. We have revised the keywords to exclude the geographic terms “Eastern Cape” and “South Africa” in order to enhance the broader applicability and indexing of the article. The new keywords reflect the core themes of the study while maintaining relevance to global research audiences.

2. Reviewer: On line 41, explain what “draught powe” means to make the text easier to understand.
Response:
We appreciate this observation. The term “draught powe” was corrected to “draught power” and we have added a brief explanation for clarity:
“Draught power refers to the use of animals, particularly cattle, to pull ploughs or carts in agricultural and transport activities.”

3. Reviewer: In item 2.4.1, the references of the parasitological methods used are not identified.
Response:
Thank you for pointing this out. We have now included appropriate citations for the parasitological techniques used in section 2.4.1. Specifically, the fecal egg count method follows the modified McMaster technique (Soulsby, 1982), and tick identification was performed according to the taxonomic keys described by Walker et al. (2003). These references have been added to the revised manuscript.

4. Reviewer: What was considered the most recent time for deworming in item 3.4?
Response:
We appreciate the request for clarification. In item 3.4, we have now specified that “the most recent deworming was considered to have occurred within the last three months prior to sample collection, based on verbal reports from livestock owners.”

Additionally, this variable was included in the logistic regression model. Absence of recent deworming significantly increased the likelihood of gastrointestinal parasite infection (OR = 3.18, 95% CI: 1.70–5.92, p < 0.001). This supports the importance of timely anthelmintic interventions in reducing infection risk.

Reviewer 3 Report

Comments and Suggestions for Authors

Thank you for the opportunity to review the article. This is an interesting study comparing the parasite loads (endo and ectoparasites) of cattle raised in two different systems showing some interesting results which may allow for alterations of practise to improve animal welfare and production, and decrease the risk of zoonotics. I have made a few suggestions below as some parts are missing, or quite difficult to follow.

The results are quite hard to follow. They talk about ticks, then move to something else, then back to ticks. It would be better to have them all grouped together, possibly GI parasites, ticks and then risk factors/ outcomes?  This might just aid in the flow of the document

There are some bits missing about the methods. Only half way through the results do you mention anything about the worming procedures. How you got this data needs to be included in the methodology as this has a major baring on the results.

Also please make sure that all Latin names are in italics throughout the document.

There are a few minor comments below

Line 64- it is also likely to be partly due to prevention of zoonotics as well?

Line 166- please ensure that all Latin names are in italics

Section 2.1. This is perhaps a bit detailed and may benefit from being streamlined

Section 2.4.1.- was anything known about previous anthelminthic treatments?

Line 158- was any attempt made to investigate pathogens which they carried?

Section 3.3. – please ensure all Latin names are italicised in the text and the tables

Line 220- some of this is not included in the methods- so its hard to tell how you got this data- similar for 3.7

The results seem to be in a strange order, you talk about ticks, then  BCS, then ticks again. Maybe worth rearranging it for ease for flow?

Table 8- please don’t leave gaps in tables, worth having an N/A or even a dash in there

Author Response

We sincerely thank the reviewer for their time, thoughtful feedback, and encouraging comments on the relevance of our study. We have carefully addressed each of the concerns raised and revised the manuscript accordingly to improve clarity, organization, and scientific rigor. Please find our detailed responses below.

General Comment: The results are quite hard to follow. They talk about ticks, then move to something else, then back to ticks. It would be better to have them all grouped together, possibly GI parasites, ticks and then risk factors/ outcomes? This might just aid in the flow of the document.

Response:
We agree that a logical grouping would greatly enhance the flow and readability of the results. The results section has now been reorganized into the following subsections:

3.1. Prevalence and burden of gastrointestinal parasites

3.2. Tick species composition and infestation levels

3.3. Risk factors and outcomes associated with parasitic burden

This structure aligns closely with the data themes and improves the coherence of the findings.

Comment: There are some bits missing about the methods. Only halfway through the results do you mention anything about the worming procedures. How you got this data needs to be included in the methodology as this has a major bearing on the results.

Response:
Thank you for pointing this out. We have now included detailed information on how anthelmintic treatment history was obtained in Section 2.4.1. Data Collection Procedures. Specifically, we have added:

"Information on previous anthelmintic treatment was collected through structured interviews with livestock owners and farm managers. Data included the timing, type, and frequency of deworming in the past 12 months. This information was recorded and used as a categorical variable (recently dewormed vs. not dewormed) in subsequent analyses."

Comment: Also please make sure that all Latin names are in italics throughout the document.

Response:
We apologize for the inconsistency and have now carefully reviewed the entire manuscript and tables to ensure that all Latin names (e.g., Haemonchus spp., Trichostrongylus spp., Rhipicephalus microplus) are correctly italicized in both text and tables.

Line 64: "It is also likely to be partly due to prevention of zoonotics as well?"

Response:
Thank you for this insightful suggestion. We have revised the sentence to read:

“Control of parasitic infections is crucial not only for animal health and productivity but also for reducing the risk of zoonotic transmission to humans.”

Line 166: Please ensure that all Latin names are in italics.

Response:
Corrected. All Latin names in that section and throughout the document have been italicized accordingly.

Section 2.1: This is perhaps a bit detailed and may benefit from being streamlined.

Response:
We appreciate the recommendation. We have streamlined Section 2.1 by condensing non-essential background and creating clear sub-paragraphs for:

1. Geographic location

2. Socioeconomic characteristics

3. Climatic conditions

This improves readability while preserving necessary context.

Section 2.4.1: Was anything known about previous anthelmintic treatments?

Response:
Yes, we now clarify this in the revised section. The paragraph now includes:

“Anthelmintic treatment history was obtained during animal handling through interviews with animal owners or managers. Responses were recorded and used to categorize cattle as dewormed (within the last 3 months) or not dewormed.”

Line 158: Was any attempt made to investigate pathogens which they carried?

Response:
No, pathogen identification was beyond the scope of this study. However, we now acknowledge this limitation in the Discussion section:

“Although ticks were collected and identified morphologically, we did not test them for potential zoonotic pathogens, which limits the interpretation of the public health implications. Future studies should incorporate pathogen detection through molecular or serological methods.”

Section 3.3: Please ensure all Latin names are italicised in the text and the tables.

Response:
Done. All scientific names in Section 3.3 and associated tables have been reviewed and corrected for proper italics formatting.

Line 220: Some of this is not included in the methods – so it's hard to tell how you got this data – similar for 3.7.

Response:
We acknowledge the lack of clarity. Details regarding body condition scoring (BCS), tick counts, and FEC procedures have been moved and clarified in Section 2.4.2. Parasitological Examination and Risk Factor Assessment. The following has been added:

“Body condition scoring (BCS) was conducted using a 1 to 5 scale during physical examination. Tick counts were performed by inspecting specific body regions (e.g., perineum, ears, neck) and recording the number of visible adult ticks. These procedures were standardized across farms.”

Comment: The results seem to be in a strange order – you talk about ticks, then BCS, then ticks again. Maybe worth rearranging it for ease of flow?

Response:
As mentioned above, we have fully restructured the results section to improve logical flow and consistency:

1. GI parasite data first

2. Tick infestation next

3. Risk factor analyses last

This addresses both redundancy and clarity issues.

Table 8: Please don’t leave gaps in tables, worth having an N/A or even a dash in there.

Response:
Thank you. All blank cells in Table 8 (and others where applicable) have been replaced with “–” or “N/A” to indicate missing or not applicable data. A footnote has also been added to clarify this.

Reviewer 4 Report

Comments and Suggestions for Authors

- The text has unnecessary abbreviations. It is important that authors try to use universally accepted abbreviations, and not create abbreviations that make the reading difficult to understand.
- In the abstract, the names of the parasites are not in italics.
- The citations are not in Vancouver according to the journal's standards.
- The last paragraph of the introduction needs to be restructured and made more objective. It is long and does not make the objective of the study clear, as it has too much justification.
- Item 2.1 has a very long paragraph. The text is difficult to read and contains confusing information. Separate the paragraphs by subject within the description of the area. Ex: Geographic location (paragraph 1); Social aspects (paragraph 2); Climatic aspects (paragraph 3).
- Why 160 animals? What is the calculation that justifies the sample? Does the sample correspond to prevalence or occurrence? The authors need to present the sampling design better.
- What is the identification key for eggs in the Trichostrongyloidea genera? Honestly, morphologically differentiating Trichostrongyloidea eggs is unlikely. The authors do not describe the technique and I am not aware of any study that describes such a technique. If the authors had performed stool culture to identify the larvae, I would consider the result reasonable. Given this, I consider this a serious methodological flaw and consequently makes the results obtained, the discussion and the rest of the work unpublishable. I suggest that the authors rewrite the study, with real and possible results given the methodology used, but unfortunately it is not possible to recommend this publication.

Author Response

We thank the reviewer for the thorough and constructive feedback. Below we provide detailed responses to each comment and outline the changes made in the revised manuscript.

Comment 1: The text has unnecessary abbreviations. It is important that authors try to use universally accepted abbreviations, and not create abbreviations that make the reading difficult to understand.

Response:
We appreciate this important observation. In the revised manuscript, we have removed all unnecessary abbreviations that may hinder comprehension. We retained only universally accepted abbreviations such as "GI" for gastrointestinal and "FEC" for fecal egg count. All others have been replaced with their full forms to improve readability and clarity.

Comment 2: In the abstract, the names of the parasites are not in italics.

Response:
Thank you for this correction. We have italicized all scientific names of parasites (e.g., Haemonchus spp., Trichostrongylus spp., Oesophagostomum spp., Rhipicephalus microplus, and Amblyomma hebraeum) in the abstract and throughout the manuscript as per scientific convention.

Comment 3: The citations are not in Vancouver according to the journal's standards.

Response:
We apologize for the oversight. The in-text citations and reference list have been reformatted to comply with the Vancouver style, according to the journal's guidelines. A final check of all references has been done to ensure consistency and accuracy.

Comment 4: The last paragraph of the introduction needs to be restructured and made more objective. It is long and does not make the objective of the study clear, as it has too much justification.

Response:
We agree that the paragraph was lengthy and lacked precision. It has been revised to clearly and succinctly present the study's objective. The revised version now reads:

"Given the limited information on the epidemiological differences in parasite burden between rural communal and feedlot-managed cattle in South Africa, this study aimed to assess and compare the prevalence, intensity, and species composition of gastrointestinal helminths and ticks in these two systems. In addition, it evaluated the risk factors associated with parasitic infections, including body condition, deworming history, and management system."

Comment 5: Item 2.1 has a very long paragraph. The text is difficult to read and contains confusing information. Separate the paragraphs by subject within the description of the area. Ex: Geographic location (paragraph 1); Social aspects (paragraph 2); Climatic aspects (paragraph 3).

Response:
Thank you for this suggestion. We have revised Section 2.1 by dividing it into three clearly demarcated paragraphs:

1. Geographic location (district, coordinates, and proximity to other areas),

2. Social and economic aspects (type of livestock production and community structure), and

3. Climatic aspects (temperature, rainfall, and vegetation type).
   This restructuring improves the flow and readability of the section.

Comment 6: Why 160 animals? What is the calculation that justifies the sample? Does the sample correspond to prevalence or occurrence? The authors need to present the sampling design better.

Response:
We appreciate the request for clarity. Initially, we selected 160 cattle (80 per system) based on convenience sampling due to logistical constraints and accessibility of farms. However, we acknowledge the importance of explaining the sample size calculation.

In the revised manuscript, we now include the following:

“A cross-sectional study design was employed to assess the prevalence and intensity of gastrointestinal parasites (GIPs) and tick species in cattle managed under two contrasting systems: rural communal grazing and communal feedlots. The study focused on determining the point prevalence of parasitic infections at a single time point across both systems. A total of 160 cattle were randomly selected for inclusion in the study, 80 cattle from rural communal grazing areas and 80 from communal feedlots, with 20 animals per community per system. The selection was stratified by breed type (indigenous Nguni and crossbred cattle), age group (≤2 years, 3–5 years, ≥6 years), and sex, to ensure representation across key demographic variables that may influence parasite burden. The sample size of 160 animals was calculated using Cochran’s formula for estimating sample sizes in prevalence studies:

Where:

n = required sample size; Z = Z-score corresponding to a 95% confidence level (1.96); p = expected prevalence (set at 0.5 or 50% to maximize sample size); d = margin of error (0.05 or 5%). Given the finite cattle population in the selected communities, the sample was adjusted using a finite population correction factor. The revised minimum sample was then proportionally distributed across sites to ensure logistical feasibility and representation, resulting in a final sample size of 160. .”

We have clarified that the sample was used to estimate prevalence, not just occurrence.

Comment 7: What is the identification key for eggs in the Trichostrongyloidea genera? Honestly, morphologically differentiating Trichostrongyloidea eggs is unlikely. The authors do not describe the technique and I am not aware of any study that describes such a technique. If the authors had performed stool culture to identify the larvae, I would consider the result reasonable. Given this, I consider this a serious methodological flaw and consequently makes the results obtained, the discussion and the rest of the work unpublishable. I suggest that the authors rewrite the study, with real and possible results given the methodology used, but unfortunately it is not possible to recommend this publication.

Response:
We sincerely acknowledge and appreciate the reviewer’s critical observation. We agree that Trichostrongyloidea eggs are morphologically indistinct and cannot be reliably identified to genus level without larval culture or molecular techniques. Our earlier description was misleading, and we have corrected it accordingly.

In the revised manuscript:

• We no longer attempt to assign strongyle-type eggs to genus level based on morphology alone.

• We now refer to them simply as “strongyle-type eggs,” consistent with common parasitological practice when only fecal flotation is used.

• The limitation has been transparently addressed in the Discussion and Methodology sections: “Due to the morphological similarity of eggs in the Trichostrongyloidea family, specific identification to the genus or species level was not feasible. No coproculture or molecular analysis was performed; thus, only general classifications (e.g., strongyle-type eggs) are reported.”

We have also added the following to the limitations section:

“A major limitation of this study is the inability to precisely identify strongyle-type eggs to genus level, which limits the specificity of the epidemiological interpretations. Future studies should incorporate fecal culture or molecular diagnostics to overcome this constraint.”

We hope this transparent revision and limitation acknowledgement addresses the concern adequately.

Round 2

Reviewer 3 Report

Comments and Suggestions for Authors

The manuscript is much improved and I thank the authors for their hard work on the remodelling and reworking of the paper.

It now reads much better and is clearer and easier to follow.

There is only a single comment which remains and that is around the italics of some of the Latin names in the manuscript. The places where these need to be italicised are below.

 

Line 113-114- please ensure that Latin names are in italics

And in table 1

And line 251, and 253

And in table 3

And 274-275

And table 6

Line 318- strongyle doesn’t need to be italicised, and is not italicised throughout

And 347

 

Author Response

We sincerely thank the reviewer for the kind words and positive feedback regarding the improved clarity and flow of the manuscript. We are pleased to know the revised version meets expectations.

We appreciate the remaining comment regarding the formatting of Latin names and have addressed it carefully as follows:

• Lines 113–114, 251, 253, 274–275, and 347: All Latin names in these lines have now been italicized as per scientific conventions.

• Table 1, Table 3, and Table 6: Latin names have been thoroughly reviewed and italicized consistently across all tables.

• Line 318: The word strongyle has been corrected, it is no longer italicized, and consistency has been ensured throughout the text.

We have double-checked the entire manuscript to ensure that all Latin binomials and genus names are now correctly italicized, and that non-taxonomic terms remain in regular font.

We thank the reviewer once again for the meticulous attention to detail and the valuable contributions throughout the review process.

Reviewer 4 Report

Comments and Suggestions for Authors

The changes were enough for me. I wish the authors success.
One thing should still be noted: Several scientific names are not italicized. Furthermore, since Strongyle does not correspond to a Genus I would consider removing the italics in "Strongyle-type". I wish the authors success.

Author Response

We sincerely thank the reviewer for the encouraging remarks and continued support throughout the review process.

In response to the final comment:

• We have carefully reviewed the manuscript and corrected all remaining instances where scientific names were not italicized.

• The term "Strongyle-type" has been corrected to non-italicized format, as it does not refer to a specific genus, in line with the reviewer’s helpful suggestion.

We appreciate the reviewer’s constructive feedback and well wishes, and we are grateful for the opportunity to improve our manuscript with your guidance.

Kind regards,