Barrels of Monkeys: Effects of Long‐term Ethanol Storage on Volar Fat Pad Morphology

Museum fluid collections preserve tissues from endangered and protected species for study. Tissues are often fixed in 10% buffered formalin to halt metabolic activities and transferred to a solution of ethanol for long term storage. This process, however, forces water from the tissues and has been shown to alter the morphology of preserved specimens in ways that may influence the biological interpretation of results. The degree to which fluid preservation alters morphology is linked to multiple biological and methodological factors and should therefore be examined prior to functional analysis. This study was conducted as part of an evaluation of mammalian volar pad morphology and comprises two analyses. In the first, a sample of rats ( Rattus norvegicus ) is utilized to evaluate longitudinal changes in the dimensions of the volar pads across fixation in 10% buffered formalin and preservation in 70% ethanol for one year. In the second, a cross‐sectional sample of fresh primate volar pads from varying species is compared to a corresponding sample from museum specimens fixed in 10% buffered formalin and preserved in 70% ethanol. No significant changes to the measured dimensions of the volar pads are present across stages of fixation and preservation, nor are significant differences evident between fresh and preserved specimen groups. These findings are likely related to the anhydrous nature of the volar fat pads and their confined position between major joints. Support or Funding Information This work was funded by NSF Doctoral Dissertation Improvement Grant #1128861. This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal .