RESUMO
Inheritance of vertical fiber hide defect (VFHD), a structural defect in collagen fiber orientation that causes weakness and reduced value of leather, was examined using histological data on hide biopsies obtained from 465 Hereford cattle by 65 sires. The data set included 44 offspring-dam pairs, for which VFHD phenotypes had been diagnosed on both the offspring and dam. Examination of offspring and parental frequency distributions indicated that inheritance of the condition was likely to be due to an autosomal recessive. In a subsequent experiment, a Hereford bull with a known VFHD phenotype was mated to Hereford cows with known VFHD phenotypes and to Angus cows not showing the defect. Angus were chosen because the defect has never been observed in the breed. All offspring (5) resulting from VFHD X VFHD matings expressed the defect, while no offspring (12) out of VFHD X non-VFHD matings (Angus cows) expressed the defect. It was concluded that VFHD is inherited as an autosomal recessive. The role that selection and alternative crossbreeding systems can play reducing phenotypic frequency of the defect is discussed.
