First Coprological Survey of Semiferal Goat (Capra hircus) Parasites in Relation to Environmental Factors on the Island of Socotra, Yemen

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The Authors report the results of parasitological analysis on fecal samples obtained from adult goats living in Socotra island (Yemen) in two different seasons (dry and rainy) and at different altitudes (highland and lowland). The analysis were conducted in Brno (Czech Republic) some months after collecting, keeping the samples fixed in 10% formalin. I have some doubts about the scientific importance of the paper considering that the parasites observed are commonly present in goats worldwide and the various results are almost costantly in line with other previous studies or  - at the end – naturally explained by the biological cycle of each parasite; innovative aspect would be the demostration of the only data in contrast with the past knowledge, in other words the greater risk of strongyle infestation during dry season, but like for other points (see lines 228-229; here 242-243; 270-271, 289-290) the Authors give only a suggestion of further inquiry with a list of mere hypothesis taken fron the bibliography and not from a specific and deep field study. For some data, especially in materials and methods, there is a severe discrepancy and the list of references (91) appears excessive in relation to the results obtained. For the above reasons and to enhance better the work done on this limited geographical area and number of samples (406), I suggest strongly to present the study in a more summary form, in other words by a brief report or a communication type paper.

Following my specific comments and suggestions (with some questions).

Line 74 (here and everywhere in the text, for example line 263, 293, etc): write the name of first Author when using the statement like “in accordance with…” or “as demonstrated by”; in this case "in accordance with Bezdek et al. [20]". 

Line 77 and farther: there is a discrepancy between 406 goats stated in line 75 and the summa of 176 and 223 (total 399) and also in the Table 1 (total 399). Check the samples.

Lines 82-87: respect the temporal sequence in the description of sampling. 1) time, site and mode of sampling (lines 84-85-86); 2) packaging and fixing of the samples (lines 82-83); 3) storage of samples (line 86). Move line 86-87 ("The analysis was conducted…) at the beginning of paragraph 2.4.

A question: why you put samples in the refrigerator if they were already fixed in formalin?

Line 104: check the word. Probably “the tube was emptied” (or the supernatant thrown away); and not the mixture (mixture is the summa of supernatant and sediment);

Line 105: give the composition of Sheather’s sugar solution.

Line 112: a question (I suggest to change the sentence to avoid doubts about the performances of the method used). If formalin can destroy the eggs, probably the results obtained are not reliable? Why flotation is damaging? If the centrifugation is the reason, the samples have been already centrifugated as stated in line 93 and so it seem that they are disappeared  at the moment of sedimentation.

Line 149: check the data. 361 infected and 45 not infected here but in  Figure 1 is reported "43 nothing".

Line 157: I suggest to consolidate (here and everywhere in the text)  the data about Muellerius spp with undetermined Protostrongylidae (they are the same group) like  you made for other parasite groups (Strongyloides spp, Strongylids, etc) among which you don’t deserve a particular attention to a specific species.

From line 159 to 205: describe the data obtained about  the parasites groups in decreasing order of prevalence (Eimeria followed by Strongylids, Trichuris….etc)

Line 215 and Figure 2: correct “nulltiple”. (the word doesnt’ exist).

Figure 2: 363 goats infected but before in line 149 they were 361. Check the data.

Line 219: the percentage 66% is referred to samples or goats? But in Figure 2, 227 multiple infected goats are 55% on 406 total goats  or 62.5 % on 363 infected goats. Please, check and describe better the data.

Line 232: a question about the season exclusivity of these parasites. After rainy season the goats in Socotra are treated against the parasites? If not, why Protostrongylidae, Muellerius sp and Trichuris are not be found in goats during dry season considering that they can persist for months without a treatment?

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

This study investigates the prevalence and seasonal patterns of gastrointestinal parasites in goats on Socotra Island, Yemen, marking the first research of its kind in the region. Using fecal samples from 406 adult goats across various locations and seasons, coprological examination revealed a high infection rate with Eimeria spp. being the most prevalent. Co-infections were common, and parasitism varied seasonally: Protostrongylidae, Muellerius spp., and Trichuris spp. were more common during the rainy season, while Eimeria spp. and gastrointestinal strongylids predominated in the dry season. This study provides essential insights for developing strategies to manage goat parasite infections in Socotra's unique environment.

The manuscript is well-prepared but requires minor revisions as outlined below.

 

Introduction

The Introduction provides sufficient and relevant information to support the manuscript's context and objectives.

Material and methods

The Materials and Methods section is adequately explained.

Results and discussion

- The authors compare the prevalence of infection in their study with that of other studies but do not discuss the reasons behind the similarities or differences observed.

- It would be beneficial if the authors explained the results by grouping the parasites based on their routes of infection, such as soil-transmitted, food-borne, or vector-borne, and provided a discussion related to these groupings.

- The authors state, 'It can be concluded that goats on Socotra Island have a lower prevalence of several parasite species compared to other studies. The reason for this requires further investigation.' I believe it is crucial to discuss this point further within the manuscript, as it could provide valuable insights into the factors influencing parasite prevalence.

- Lines 265-271 also require further discussion. The finding that Strongyloides is present throughout the year, while it is typically not observed in other regions, is particularly interesting and warrants more in-depth discussion regarding the differences in ecosystems.

Conclusion

The conclusion would benefit from stronger information regarding how the ecosystem of the studied areas influences parasitic infections in goats.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

Thanks to the Authors for addressing almost all comments and suggestions given in the report 1 (especially them related to some uncorrect data)  and also for the willingness to discuss the most doubtful passages or statements. Regarding the storage of formalinized samples in the refrigerator, as it is an uncommon practice in developed countries, I still suggest to specify in the text (line 89) the reasons related to high temperatures of Socotra island and the real risk of evaporation as you kindly explained (I hope that my request will help to improve the understanding of the method for all readers worldwide).

Author Response

Comments 1: Thanks to the Authors for addressing almost all comments and suggestions given in the report 1 (especially them related to some uncorrect data)  and also for the willingness to discuss the most doubtful passages or statements. Regarding the storage of formalinized samples in the refrigerator, as it is an uncommon practice in developed countries, I still suggest to specify in the text (line 89) the reasons related to high temperatures of Socotra island and the real risk of evaporation as you kindly explained (I hope that my request will help to improve the understanding of the method for all readers worldwide).

Response 1: We appreciate your recommendation. The inclusion of this information to the text as we believe that its inclusion will be useful for improving the methodology and other researchers in the field.