The second animal experiment assessed the long-term efficacy of BVCARHAdV5-PUMA during 21 days compared to HAdV5-PUMA alone (both 109 PFU per joint; n = 7 per group). The clinical parameters monitored during these experiments, including articular index, mobility index, ankle circumference and body weight. Articular index scores were recorded for each hind joint by a consistent observer blinded to the treatment regimen and then averaged for each animal. Scoring was performed on a 0–4 scale where 0 = no swelling or erythema, 1 = slight swelling and/or erythema, 2 = low-to-moderate oedema, 3 = pronounced oedema with limited joint usage and 4 = excess oedema with joint rigidity. Mobility index were also recorded in the same way and provided limb function with a scale from 0 to 4 where 0 = regular mobility, 1 = gait irregularities, intermittent lameness, 2 = continuous lameness, with use of the forefoot only, 3 = continuous lameness, use of the top of the paw by bending the metatarsals, and 4 = loss of function, no use of the paw. Ankle circumferences were evaluated as the perimeter calculated after antero-posterior and latero-lateral ankle measurement with digital caliper.