A randomized, double-blind, controlled study on the efficacy of an oral dietary supplement containing fish oil, ASU and phytotherapeutic extracts in canine osteoarthritis

Osteoarthritis (OA) is a common musculoskeletal disorder in canines, characterized by discomfort, lameness, and reduced mobility. Because of the inconsistent efficacy of available treatments, and that a definitive resolution can be achieved only in a small number of cases, OA remains a major challenge in veterinary orthopedics. The current strategy is usually a multimodal approach involving systemic administration of anti-inflammatory drugs, intra-articular therapies, physiotherapy, dietary modifications, and nutraceuticals. The main goals are to slow progression, preserve joint function, and alleviate pain and inflammation. Although non-steroidal anti-inflammatory drugs (NSAIDs) are effective agents for controlling OA signs, their long-term use is associated with adverse effects. Therefore, in recent years, growing attention has been directed toward nutraceutical compounds. Thanks to their natural origin and safety, these products have shown promising results in reducing pain and inflammation in dogs with spontaneous osteoarthritis, representing a valuable alternative or complementary option. The aim of this study was to evaluate the efficacy of a nutraceutical formulation, mainly composed of fish oil, unsaponificable fraction from Avocado and Soy seeds, Turmeric extract, Devil's Claw, Boswellia, <i>Salix alba</i> extract, <i>Piper nigrum</i>, <i>Haematococcus pluvialis</i>, Magnesium salt of stearic acid, maltodextrin (Asudyn^®), by comparing its short- and mid-term clinical, radiographic, and cytological outcomes with those obtained from treatment with mavacoxib (Trocoxil^®), a selective COX-2 inhibitor. Twenty dogs were enrolled and randomly assigned into two groups. Group A received oral administration of Asudyn^® for 90 consecutive days, whereas Group B was treated with Trocoxil^® at T0, T15, T45, and T75. Clinical evaluations were conducted at baseline (T0) and at 30, 60, and 180 days after treatment initiation. Lameness was assessed using the Numerical Rating Scale (NRS), pain with the Canine Brief Pain Inventory (CBPI) and Visual Analog Scale (VAS). Additional parameters included limb circumference (CRF), Total Pressure Index (TPI %), and Gait Lameness Score (GLS %). Synovial fluid sampling and radiographic examinations were performed at T0, T30, and T60. The results showed that Asudyn^® had efficacy comparable to Trocoxil^® in reducing pain, improving lameness, and enhancing synovial fluid quality. Overall, Asudyn^® proved as effective as, and sometimes superior to, mavacoxib in managing canine OA.