Committee: Cássio Ricardo Auada Ferrigno (USP), João Eduardo Wallau Schossler (UFSM), Carlos Afonso de Castro Beck (UFRGS) Cats with orthopedic conditions are a prominent part of the clinical work of veterinary traumatologists. Conditions such as comminuted fractures of the long bones, bone cancers and non-unions or unions that repeatedly fracture are often difficult to repair surgically and may require the use of bone grafts or implants for successful treatment. This study evaluated cortical bone allografts preserved in honey, frozen at-70°C or lyophilized for correcting 3cm long bone defects created in the diaphysis of the right femur of adult domestic cats (n=24). In the control group (n=6), the defect was repaired using the autologous bone following removal of the periosteum, endosteum and bone marrow. In the remaining animals (n=6/group), the defect was repaired with cortical bone allografts preserved in honey, frozen or lyophilized. Success of implant incorporation and length of time for consolidation were assessed through clinical, radiographic and histological evaluations performed up to 180 days after surgery. In the control, frozen, honey and lyophylized groups, respectively, success of implant incorporation was 91.6%, 83.3%, 75%, and 25%, with corresponding mean length of time for consolidation of 83.1, 78, 105 and 120 days. Consolidation percentage in the lyophilized group was significantly lower than in the frozen and control groups. Length of time for consolidation was not different between the groups. Brevibacterium spp. was isolated from one of the implants preserved in honey. In conclusion, bone grafts preserved in honey or frozen at-70°C were effective for repairing cortical defects in the femurs of adult cats as compared to autologous bone. Lyophilized implants require more evaluation of resistance and immunogenicity before they can be considered a viable option for bone repair in cats.