Quantification of vertical-fiber defect in cattle hide by small-angle light scattering.

Vertical-fiber defect (VFD), an abnormal arrangement of collagen fibers in hides of certain cattle breeds, is still not fully understood. Prior work has been limited to subjective histological examinations from hide biopsies. A device using small angle light scattering (SALS) was used to quantify the collagen fiber orientation of sections taken from hide biopsies. Sections were chosen from the Hereford cattle breed and classified by conventional observation as belonging to either the normal, intermediate, or vertical phenotypes. The vertical fibers occur only in the upper reticular dermis, with the fibers in the lower reticular dermis lying parallel to the plane of the hide in all phenotypes. By SALS the vertical phenotype was found to be significantly different from the normal phenotype, whilst the intermediate phenotype was found to be structurally indistinguishable from the vertical one. No evidence was found for the existence of other phenotypes.