The effect of housing environment on bone healing in a critical radius defect in New Zealand White rabbits

Abstract

In animal studies on bone healing, the effect of housing space and physical activity are seldom taken into account. Bone formation was evaluated in New Zealand White rabbits (mean +/- SEM BW: 3.9 +/- 0.11 kg) with a critical bone defect after 12 weeks of rehabilitation in pair-housing in 3 m(2) large floor pens (Floor, n = 10) or standard single housing in 0.43 m(2) cages (Cage, n = 10). In the randomised full-factorial study, a bone replica of calcium phosphate cement (CPC, n = 10) or autologous bone (AB, n = 10) was implanted in the unilateral 20 mm radius defect. Post-mortem, the oxidative capacity was measured by citrate synthase (CS) activity in M. quadriceps and the defect filling volume and density evaluated by microcomputer tomography (mu- CT). Histology sections were evaluated by subjective scoring and histomorphometry. Fourteen rabbits remained until the end of the study. Group Floor (n = 7; 3 CPC + 4 AB) had a higher CS activity and a larger bone defect filling volume and lower density by mu- CT measurements than group Cage (n = 7; 3 CPC + 4 AB). Three out of four rabbits in AB-Floor presented fusion of the defect with reorganisation of trabecular bone, whereas three of four in AB-Cage showed areas of incomplete healing. Floor rabbits had a higher score of bony fusion between the radius and ulna than Cage rabbits. There were no differences between groups in histomorphometry. The study found that a larger housing space increased physical activity and promoted bone formation.

Published in

PLoS ONE
2020, volume: 15, number: 5, article number: e0233530
Publisher: PUBLIC LIBRARY SCIENCE

SLU Authors

• Hedenqvist, Patricia

  • Department of Clinical Sciences, Swedish University of Agricultural Sciences
    

• Manell, Elin

  • Department of Clinical Sciences, Swedish University of Agricultural Sciences
    

• Ekman, Stina

  • Department of Clinical Sciences, Swedish University of Agricultural Sciences
    

• Ley, Cecilia

  • Department of Animal Biosciences, Swedish University of Agricultural Sciences
    

• Jensen Waern, Marianne

  • Department of Clinical Sciences, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Animal and Dairy Science

Publication identifier

• DOI: https://doi.org/10.1371/journal.pone.0233530

Permanent link to this page (URI)

https://res.slu.se/id/publ/106643