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Animals : an open access journal from MDPI2023; 13(10); 1672; doi: 10.3390/ani13101672

Morphology of the Ventral Process of the Sixth Cervical Vertebra in Extinct and Extant Equus: Functional Implications.

Abstract: In this study, we examined the ventral process of C6 in extinct and extant (sister taxa to only) with the purpose of describing normal morphology and identifying anomalous variations relevant to recent studies describing a congenital malformation in . Overall, 83 specimens from 9 museums and 3 research/educational facilities were examined, totalling 71 extinct specimens from 12 species and 12 extant specimens from 5 species. The lateral view revealed that a large convexity exists in the ventral process between the cranial ventral tubercle (CrVT) and the caudal ventral tubercle (CVT) in the earliest ancestor, , from 55 mya, which receded throughout the millennia to become a smaller convexity in and the sister taxa. The CrVT is visibly shorter and narrower than the CVT, with a constricted section directly ventral to the transverse process, essentially demarcating the CrVT and CVT. No congenital malformations were evident. As the ventral process of C6 is an integral component for muscle attachment in supporting the head/neck during posture and locomotion, this would indicate that the caudal module in the cervical column might be compromised when a partial or complete absence of the CVT is detected via radiographs in modern .
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Publication Date: 2023-05-17 PubMed ID: 37238101PubMed Central: PMC10215204DOI: 10.3390/ani13101672Google Scholar: Lookup
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  • Journal Article

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 discusses the examination of a particular bone structure in extinct and presently existing species of a group of animals. The focus is to understand changes in the bone structure over time and any abnormalities that may be associated with certain health conditions.

Introduction and Purpose of the Study

  • The research focuses on investigating the ventral process of C6, a part of the cervical vertebral column, in both extinct and extant species of Equus.
  • The purpose of this investigation is to describe the normal bone structure and identify any anomalous variations that might be related to a congenital malformation previously reported in recent studies. Here, Equus is a genus of animals that includes horses and similar species.

Data and Study Method

  • The study analyzed a total of 83 specimens from 9 different museums and 3 research or educational facilities. This includes 71 extinct species from 12 different species and 12 specimens from 5 extant species.

Findings of the Study

  • A dent or large convexity was found in the ventral process between the cranial ventral tubercle (CrVT) and the caudal ventral tubercle (CVT) in the earliest ancestor from 55 million years ago. This convexity receded over time to become a smaller dent in the currently existing species.
  • The cranial ventral tubercle (CrVT) is visibly shorter and narrower than the caudal ventral tubercle (CVT), with a constricted section directly below the transverse process, essentially marking the difference between the CrVT and CVT.
  • The examination of the samples did not reveal any congenital malformations.

Implications and Interpretations

  • Due to the role of the ventral process of the C6 vertebra in muscle attachment and support for the head and neck during movements, its abnormality or absence might result in compromised movement and posture. This also indicates that the caudal module in the cervical column might be disrupted when a partial or complete absence of the CVT is detected using X-rays in modern specimens.

Cite This Article

APA
May-Davis S, Hunter R, White R. (2023). Morphology of the Ventral Process of the Sixth Cervical Vertebra in Extinct and Extant Equus: Functional Implications. Animals (Basel), 13(10), 1672. https://doi.org/10.3390/ani13101672

Publication

Animals : an open access journal from MDPI
ISSN: 2076-2615
NlmUniqueID: 101635614
Country: Switzerland
Language: English
Volume: 13
Issue: 10
PII: 1672

Researcher Affiliations

May-Davis, Sharon
  • Canine and Equine Research Group, University of New England, Armidale, NSW 2351, Australia.
Hunter, Robert
  • Canine and Equine Research Group, University of New England, Armidale, NSW 2351, Australia.
White, Richard
  • Mammoth Site, Hot Springs, SD 57747, USA.

Conflict of Interest Statement

The authors declare no conflict of interest.

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Citations

This article has been cited 4 times.
  1. May-Davis S, Dzingle D, Saber E, Blades Eckelbarger P. Characterization of the Caudal Ventral Tubercle in the Sixth Cervical Vertebra in Modern Equus ferus caballus. Animals (Basel) 2023 Jul 22;13(14).
    doi: 10.3390/ani13142384pubmed: 37508161google scholar: lookup
  2. DeClue A, Workman K, May-Davis S. Identifying by Radiograph Grade 4 Aplasia of the Caudal Lamina Ventralis in the Equine Sixth Cervical Vertebra and Three Coinciding Morphological Variations. Animals (Basel) 2026 Feb 4;16(3).
    doi: 10.3390/ani16030482pubmed: 41681463google scholar: lookup
  3. May-Davis S, Eckelbarger PB, Dzingle D, Saber E. Characterization and Association of the Missing Ventral Tubercle(s) from the Sixth Cervical Vertebra and Transpositions on the Ventral Surface of the Seventh Cervical Vertebra in Modern Equus ferus caballus. Animals (Basel) 2024 Jun 20;14(12).
    doi: 10.3390/ani14121830pubmed: 38929448google scholar: lookup
  4. Zimmermann E, Ros KB, Pfarrer C, Distl O. Historic Horse Family Displaying Malformations of the Cervicothoracic Junction and Their Connection to Modern German Warmblood Horses. Animals (Basel) 2023 Nov 3;13(21).
    doi: 10.3390/ani13213415pubmed: 37958170google scholar: lookup
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