RESUMEN
There is a paucity of scientific data on the effect of shoeing on equine neck and back kinematics during locomotion over commonly used sand training surfaces. A better appreciation of how alterations at hoof-ground interface influence equine upper body movements is relevant for improving horse's health and performance. Our objectives were to determine the effects of different shoeing conditions on equine neck and back kinematics at walk and trot in straight line over sand. Two-dimensional kinematic video analysis was performed under seven shoeing conditions: front feet shod with aluminum shoes and hind feet with steel racehorse shoes (REFSHOD), front aluminum shoe and hind feet unshod (FORESHOD), front feet unshod and hind steel race shoes (HINDSHOD), all four feet unshod (UNSHOD), front feet shod in combination with hind egg bar shoes (hEGGBAR), hind wide toe shoes (hTOE) and hind reverse shoes (hREVERSE). Data indicated that joint angles in the cervicothoracic junction were four times more likely to be significantly affected by the shoeing condition than in the back and sacrum. FORESHOD largely modifies the kinematics in comparison to REFSHOD or UNSHOD, with respectively a 6-11±1-2° (P<0.001) increased cervicothoracic extension at walk and trot, and a 3-4±1° (P<0.05) increased thoracolumbar flexion at trot. In comparison to REFSHOD, hEGGBAR, hTOE and hREVERSE induce a 5-7±1-2° (P<0.05) increased cervicothoracic extension at trot and walk respectively, and UNSHOD induced cervicothoracic flexion at trot (6±2°, P<0.05). In conclusion, shoeing conditions impact equine neck and back position, which should be considered during clinical examination, rehabilitation and training.
RESUMEN
The global decline of freshwater mussels and their crucial ecological services highlight the need to understand their phylogeny, phylogeography and patterns of genetic diversity to guide conservation efforts. Such knowledge is urgently needed for Unio crassus, a highly imperilled species originally widespread throughout Europe and southwest Asia. Recent studies have resurrected several species from synonymy based on mitochondrial data, revealing U. crassus to be a complex of cryptic species. To address long-standing taxonomic uncertainties hindering effective conservation, we integrate morphometric, phylogenetic, and phylogeographic analyses to examine species diversity within the U. crassus complex across its entire range. Phylogenetic analyses were performed using cytochrome c oxidase subunit I (815 specimens from 182 populations) and, for selected specimens, whole mitogenome sequences and Anchored Hybrid Enrichment (AHE) data on â¼ 600 nuclear loci. Mito-nuclear discordance was detected, consistent with mitochondrial DNA gene flow between some species during the Pliocene and Pleistocene. Fossil-calibrated phylogenies based on AHE data support a Mediterranean origin for the U. crassus complex in the Early Miocene. The results of our integrative approach support 12 species in the group: the previously recognised Unio bruguierianus, Unio carneus, Unio crassus, Unio damascensis, Unio ionicus, Unio sesirmensis, and Unio tumidiformis, and the reinstatement of five nominal taxa: Unio desectusstat. rev., Unio gontieriistat. rev., Unio mardinensisstat. rev., Unio nanusstat. rev., and Unio vicariusstat. rev. Morphometric analyses of shell contours reveal important morphospace overlaps among these species, highlighting cryptic, but geographically structured, diversity. The distribution, taxonomy, phylogeography, and conservation of each species are succinctly described.