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Home / Equine Research Bank / Animals (Basel) / Morphometric Characteristics of the Skull in Horses and Donk...
Animals : an open access journal from MDPI2020; 10(6); 1002; doi: 10.3390/ani10061002

Morphometric Characteristics of the Skull in Horses and Donkeys-A Pilot Study.

Abstract: Horses and donkeys belong to the genus Equus, but important differences exist between the species, many of which affect their management and welfare. This study compared skull morphology between horses and donkeys. Horse ( = 14) and donkey ( = 16) heads were obtained post-mortem, sectioned sagittally close to the midline, and photographed for subsequent measurement of various skull structures. Skull, cranial, nasal, and profile indices were calculated for topographical comparisons between the species. The olfactory bulb area (OBA), OB pitch (the angle between the hard palate and the OB axis), and whorl location (WL) were also measured. A General Linear Model determined the main effect of species with Sidak's multiple comparisons of species' differences among the various measurements. There was no species difference in cranial or nasal indices ( > 0.13), but donkeys had a larger cranial profile than horses ( < 0.04). Donkeys had a smaller OBA ( < 0.05) and a steeper OB pitch ( < 0.02) than horses. The WL corresponded to the level of the OB in horses but was extremely rostral in donkeys ( < 0.0001). These results show clear differentiation in skull morphology between horses and donkeys. This may be useful in validating other physiological and behavioural differences between horses and donkeys.
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Publication Date: 2020-06-08 PubMed ID: 32521777PubMed Central: PMC7341236DOI: 10.3390/ani10061002Google Scholar: Lookup
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Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research article is a comparative study which investigates the differences in skull morphology between horses and donkeys, highlighting the distinct characteristics between the two species that are both from the genus Equus.

Study Design and Procedures

  • In this study, the researchers used 14 horse heads and 16 donkey heads, which were obtained post-mortem.
  • The heads were sectioned sagittally, which is a vertical cut, close to the midline and then photographed for further measurements.
  • Different parts of the skull, including cranial, nasal, and profile characteristics were measured and their indices were calculated for comparison between the species.
  • Additionally, other measurements like the olfactory bulb area (OBA), the olfactory bulb (OB) pitch, and whorl location (WL) were also taken. The OBA is the area of the brain involved in the sense of smell, while the OB pitch refers to the angle between the hard palate and the axis of the OB. The WL refers to the specific positioning of hair whorls, which is a pattern in which hair grows from a point.
  • A General Linear Model was used to determine the species’ main effects, and Sidak’s multiple comparisons were used to identify specific differences between the species.

Key Findings

  • There were no significant differences identified in the cranial or nasal indices between horses and donkeys.
  • However, donkeys were found to have a larger cranial profile compared to horses.
  • Donkeys also had a smaller olfactory bulb area and a steeper OB pitch compared to horses.
  • In the case of the whorl location, it was found to align with the level of the olfactory bulb in horses, but it was much further forward in donkeys.

Significance and Potential Applications

  • The research provides clear evidence of differentiation in skull morphology between horses and donkeys.
  • These findings could be used to validate other physiological and behavioural differences between the two species.
  • This could be significant for effective management and welfare of horses and donkeys, and may provide important insights for veterinary and animal behavioural studies.

Cite This Article

APA
Merkies K, Paraschou G, McGreevy PD. (2020). Morphometric Characteristics of the Skull in Horses and Donkeys-A Pilot Study. Animals (Basel), 10(6), 1002. https://doi.org/10.3390/ani10061002

Publication

Animals : an open access journal from MDPI
ISSN: 2076-2615
NlmUniqueID: 101635614
Country: Switzerland
Language: English
Volume: 10
Issue: 6
PII: 1002

Researcher Affiliations

Merkies, Katrina
  • Department of Animal Biosciences, University of Guelph, Guelph, N1G 2W1 ON, Canada.
  • Campbell Centre for the Study of Animal Welfare, University of Guelph, Guelph, N1G 2W1 ON, Canada.
Paraschou, George
  • The Donkey Sanctuary, Sidmouth, Devon EX10 0NU, UK.
McGreevy, Paul Damien
  • Sydney School of Veterinary Science, Faculty of Science, University of Sydney, Sydney, NSW 2006, Australia.

Conflict of Interest Statement

The authors declare no conflict of interest.

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Citations

This article has been cited 5 times.
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