This is an interesting and important area for review, but there are a number of issues around the methodology and how the paper is presented that needs addressing. Most importantly, this needs to follow the PRISMA format, as it is currently confusing as to where some of the information came from, and why you are using data from excluded publications.
Abstract -aim - should be in past tense not present. Please change to : 'The purpose of this scoping review was to explore'
Abstract should follow PRISMA guidelines and include eligibility criteria, sources of evidence and charting methods
Line 83-83 - the authors say they used the Prisma guidelines, but the paper does not follow these and does not use the subtitles and sections as outlined. The PRISMA checklist included shows that several key steps and sections were not completed.
No information provided on protocol and registration. Dates of searches should be given not just month. Information on charting and critical appraisal should be included.

Additional specific details:
Google searches included terms which were not used in the database searches (racetrack, competition and endurance), and unclear why these terms were used and not others, e.g. racehorse, dressage, showjumping, eventing
Lines 129-163 needs rewriting in methods and results. If these papers were excluded, then it is not clear why they were read and analysed. If the original inclusion criteria need revising, then this should be done, and a new search and inclusion criteria defined and the results redone. It is not currently clear here whether the papers listed were included or excluded, and if they were excluded, how you have then presented data from them
Line 137 'Firstly, the ethics of using horses in sport was identified.' - these were your search terms, so it does not make sense to describe this as a theme that emerged from analysis. The areas identified in live 137-162 is essentially a list of ethical concerns, and if this section is rewritten and included, these would be better presented as a table.
Results is excessively long, currently includes discussion, and instead needs to present findings in a logical order, as indicated by the PRISMA guidelines. Lines 165-66 and 174-175, for example are discussion. Lines 175-178 are characteristics of sources of evidence, which should be presented before the critical appraisal, and include more detail, for example the number of studies from each country. This section needs restructuring into the PRISMA format.
Supplementary item 1 - please include date of publication. Listing by alphabetical paper title does not seem that logical - would suggest restructuring by publication type first, and then author name
I would encourage the authors to go back to the PRISMA guidelines and checklist and review and reformat this into a conventional manner, which clearly outlines, charts and maps the evidence in this area. This would make a significant contribution to this area of veterinary literature when reformatted.

Thank you for submitting this revision, and the revised paper now follows the PRISMA format and sections. The only remaining minor changes that I think now need doing is the formatting of the references - some journals / conference proceedings are written out in full, and some are abbreviated. EVJ uses the abbreviate format, so these need checking and amending.