Journal of Cytology & Histology

Histomorphometric Density Measurement of Bone Marrow Cellularity in Broiler Chickens

Abstract

Floyd D. Wilson*, Lanny Pace and Frederic J. Hoerr

Routine 5 μm H&E-stained histologic bone sections were utilized to investigate the capability of histomorphometry for determining bone marrow cellularity in commercial broiler chickens. Bone marrow mean pixel density was measured using the NIH ImageJ software program and the results for binary digital images were compared to corresponding results for actual bone marrow cell counts and cellular density scoring. A total of 220 bone marrow samples from femur and tibia obtained from broiler chickens, aged from hatch to 42 days were investigated. The average and standard deviation for all density measurements was 117 ± 26 pixels, for all cell counts 312 ± 124 cells per grid field and for all density scores 3.4 ± 0.8. Bone marrow density measurements from binary digital images and cellularity counts were highly correlated (correlation coefficient +0.83). Although more subjective semi quantitative density scoring procedures produced similar and significant age-associated profiles, the scoring results had a lower correlation with density (+0.59) and with cell counts (correlation +0.64). The density method provides a rapid approach for the evaluation of bone marrow cellularity using routine bone marrow histologic sections, standard microscopy, free software, and archived specimens. New bone marrow data are reported on age-associated changes occurring in the bone marrow of broiler chickens raised in a commercial environment.