Comparative Physiological Profiling of Abalone (Haliotis iris): Insights from Wild and Aquaculture Broodstock

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Overall this is an interesting paper. My comments are relatively minor and will be identified by referring to specific lines in the mss.

Line 45 - a map showing specific locations would be useful

Line 55 - I am not convinced by the use of the word "iconic"

Figure 1 - does not make it clear whether males and females were analysed separately

I do not think it necessary to give the country of manufacture of each piece of equipment used (e.g. Line 195 and 214)

There is inconsistency in referencing - sometimes references are identified by number and sometimes by author's name. Please use consistent method.

Line 462 +++ The fact that the spawning condition of the animals under investigation was not known, is a major problem with this section. Obviously, several of the measurements made in this section would be affected by spawning condition and, as this was not known, authors should state this limitation more strongly. 

Line 510- 527 The information presented on buccal cavity microflora is very generalised because the specific food composition of each group is not presented. It should be made more clear, therefore, that these statements are of a general nature, and do not refer specifically to the experimental groups.

Author Response

REVIEWER 1

Overall, this is an interesting paper. My comments are relatively minor and will be identified by referring to specific lines in the mss.

 

Reviewer #1:    Line 45 - a map showing specific locations would be useful

Response:       We thank the reviewer for the suggestion. Specific collection locations are publicly available on the Fisheries New Zealand website (https://fs.fish.govt.nz/Page.aspx?pk=7&tk=100&sc=PAU) and can be accessed by readers, where of interest.

 

Reviewer #1:    Line 55 - I am not convinced by the use of the word "iconic"

Response:       The word iconic was removed from the main text.

 

Reviewer #1:    Figure 1 - does not make it clear whether males and females were analysed separately.

Response:       The figure has been updated to clearly indicate that male and female abalone were analysed separately. This information has also been added to the figure caption for clarity.

 

Reviewer #1:    I do not think it necessary to give the country of manufacture of each piece of equipment used (e.g. Line 195 and 214).

Response:       We thank the reviewer for this suggestion. The country of manufacture has been removed from the manuscript for all equipment references.

 

Reviewer #1:    There is inconsistency in referencing - sometimes references are identified by number and sometimes by author's name. Please use consistent method.

Response:       Thank you for noting this. All references have now been formatted consistently according to journal requirements.

 

Reviewer #1:    Line 462 +++ The fact that the spawning condition of the animals under investigation was not known, is a major problem with this section. Obviously, several of the measurements made in this section would be affected by spawning condition and, as this was not known, authors should state this limitation more strongly.

Response:       We agree. Unfortunately, this information from wild stocks is not available. This has been noted as a limitation of the study (lines 468–469).

 

Reviewer #1:    Line 510- 527 The information presented on buccal cavity microflora is very generalised because the specific food composition of each group is not presented. It should be made clearer, therefore, that these statements are of a general nature, and do not refer specifically to the experimental groups.

Response:       Th We appreciate the reviewer’s observation. The statements regarding potential dietary influences on the buccal cavity microbiota were intended as general context rather than specific conclusions about the diets of the experimental groups. To clarify this, we have revised the paragraph to explicitly state that dietary composition was not characterised and that the discussion of diet–microbiota relationships should be considered general in nature.

Reviewer 2 Report

Comments and Suggestions for Authors

This is a baseline physiological and health assessment of farmed and wild caught Haliotis iris in New Zealand.

1. The research is well justified as the knowledge base for this abalone species needs to expand to support aquaculture techniques.

2. The overall experimental approach uses many biomarkers for the assessment which is commendable. One question is about the low number of animals used and seasonal variability is not included in the study.

3. The histology did not include all tissues, especially muscle and ganglia for a more complete health assessment.

4. There was no apparent sedation or anaesthesia used for humane euthanasia of the experimental animals.

5. The results are well presented and clear, easy to understand and follow.

6. The conclusions are generally well supported and suggestions for future work on this abalone are appropriate.

7. The paper is suitable for publications after minor revisions.

Comments for author File: Comments.pdf

Author Response

REVIEWER 2

This is a baseline physiological and health assessment of farmed and wild caught Haliotis iris in New Zealand. The research is well justified as the knowledge base for this abalone species needs to expand to support aquaculture techniques. The paper is suitable for publications after minor revisions.

 

Reviewer #2:    What is the statistic power of this sample number? What are the assumptions about the baseline variability of the parameters to be measured, which may require a higher sampling number to see statistical differences between the 2 groups of abalone studied?

Response:       We thank the reviewer for this valuable comment. The number of animals analysed in this study was determined by the availability of representative individuals from each population at the time of sampling. The statistical analyses applied were appropriate for the data structure, and variance within groups was considered in all tests performed. The sample size used provided sufficient replication for the comparative analyses undertaken and aligns with the replication commonly applied in comparable metabolomics and microbiota studies on Haliotis species [(Nguyen, et al (2025). A multi-platform metabolomics approach to investigate the effects of acute thermal stress on New Zealand black-footed abalone (Haliotis iris). Fisheries Research, 287, 107426 & Bullon et al. (2025). Expanding the menu for New Zealand farmed abalone: dietary inclusion of insect meal and grape marc (effects on gastrointestinal microbiome, digestive morphology, and muscle metabolome). New Zealand Journal of Marine and Freshwater Research, 59(1), 31-60]. We agree that larger sample numbers can increase confidence in statistical comparisons.

 

Reviewer #2:    Was an anaesthetic agent used to euthanase the abalone before dissection? 

Response:       No, the animals were not anaesthetised prior to dissection. Anaesthetic agents are known to alter metabolite profiles, as demonstrated in our previous work on mussels (Azizan et al. (2021). Beyond relaxed: magnesium chloride anaesthesia alters the circulatory metabolome of a marine mollusc (Perna canaliculus). Metabolomics, 17(8), 73). To avoid introducing such artefacts, abalone were dissected immediately using standardised and published procedures (Nguyen et al. (2022). Investigating the biochemical effects of heat stress and sample quenching approach on the metabolic profiling of abalone (Haliotis iris). Metabolomics, 18(1), 7), in accordance with institutional animal handling standards.

 

Reviewer #2:    Were adductor muscle and peripheral nerves or ganglia not included for histology? Abalone Viral Ganglioneuritis (AVG) is a significant abalone disease to consider as a baseline health parameter for culture of abalone, and muscle/ganglia are important histological tissues to examine.

Response:       Yes, a full histological assessment was performed on the abalone under study. A range of tissues, including the midgut, digestive gland, gills, gonad, kidneys, hypobranchial gland, nervous tissue (ganglia), and muscle, were examined histologically for signs of pathology or infection. No abnormalities or differences were observed between the farmed and wild populations. Additional information has now been incorporated into the manuscript to confirm the absence of pathogens, parasites or diseases in both populations.

 

Reviewer #2:    Baseline only. More animal would need to be examined for a comprehensive assessment, also any variability across seasons, taking into account spawning activity

Response:       Agreed, the comprehensive have been replaced with baseline in this instance to accurately reflect the actions of the study. The limitations of animal size, lack of spawning data and seasonal variability is now highlighted in the manuscript.

 

Reviewer #2:    More tissues to be sampled including muscle and ganglia for a comprehensive health assessment.

Response:       We agree that a more comprehensive assessment, including additional tissues such as ganglia, would provide further insight into abalone health and could be incorporated in future studies. Examination of ganglia, however, falls outside the primary scope of the present study. Muscle tissue was assessed in the current work, primarily in the context of overall condition, which is directly relevant to aquaculture performance.

 

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

Responses from authors accepted.