Planar Covariation of Hindlimb and Forelimb Elevation Angles during Terrestrial and Aquatic Locomotion of Dogs

PLoS One. 2015 Jul 28;10(7):e0133936. doi: 10.1371/journal.pone.0133936. eCollection 2015.

Abstract

The rich repertoire of locomotor behaviors in quadrupedal animals requires flexible inter-limb and inter-segmental coordination. Here we studied the kinematic coordination of different gaits (walk, trot, gallop, and swim) of six dogs (Canis lupus familiaris) and, in particular, the planar covariation of limb segment elevation angles. The results showed significant variations in the relative duration of rearward limb movement, amplitude of angular motion, and inter-limb coordination, with gait patterns ranging from a lateral sequence of footfalls during walking to a diagonal sequence in swimming. Despite these differences, the planar law of inter-segmental coordination was maintained across different gaits in both forelimbs and hindlimbs. Notably, phase relationships and orientation of the covariation plane were highly limb specific, consistent with the functional differences in their neural control. Factor analysis of published muscle activity data also demonstrated differences in the characteristic timing of basic activation patterns of the forelimbs and hindlimbs. Overall, the results demonstrate that the planar covariation of inter-segmental coordination has emerged for both fore- and hindlimbs and all gaits, although in a limb-specific manner.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Biomechanical Phenomena
  • Dogs
  • Ecosystem*
  • Environmental Monitoring*
  • Forelimb / physiology*
  • Functional Laterality / physiology*
  • Gait / physiology
  • Hindlimb / physiology*
  • Locomotion / physiology*
  • Male
  • Running / physiology
  • Walking / physiology

Grants and funding

This work was supported by grants from the Italian University Ministry (PRIN project grant 2010MEFNF7_002) and the Italian Space Agency (COREA grant). GC is supported by the PhD program in Neurosciences of the University of Rome Tor Vergata. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.