Evaluation of avocado and soybean unsaponifiable extracts for treatment of horses with experimentally induced osteoarthritis

Am J Vet Res. 2007 Jun;68(6):598-604. doi: 10.2460/ajvr.68.6.598.


Objective: To evaluate the use of a combination of avocado and soybean unsaponifiable (ASU) extracts for the treatment of experimentally induced osteoarthritis in horses.

Animals: 16 horses.

Procedures: Osteoarthritis was induced via osteochondral fragmentation in 1 middle carpal joint of each horse; the other joint underwent a sham operation. Horses were randomly allocated to receive oral treatment with ASU extracts (1:2 [avocado-to-soybean] ratio mixed in 6 mL of molasses; n = 8) or molasses (6 mL) alone (placebo treatment; 8) once daily from days 0 to 70. Lameness, response to joint flexion, synovial effusion, gross and histologic joint assessments, and serum and synovial fluid biochemical data were compared between treatment groups to identify effects of treatment.

Results: Osteochondral fragmentation induced significant increases in various variables indicative of joint pain and disease. Treatment with ASU extracts did not have an effect on signs of pain or lameness; however, there was a significant reduction in severity of articular cartilage erosion and synovial hemorrhage (assessed grossly) and significant increase in articular cartilage glycosaminoglycan synthesis, compared with placebo-treated horses.

Conclusions and clinical relevance: Although treatment with ASU extracts did not decrease clinical signs of pain in horses with experimentally induced osteoarthritis, there did appear to be a disease-modifying effect of treatment, compared with findings in placebo-treated horses. These objective data support the use of ASU extracts as a disease-modifying treatment for management of osteoarthritis in horses.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Horse Diseases / drug therapy*
  • Horses
  • Osteoarthritis / drug therapy
  • Osteoarthritis / veterinary*
  • Persea / chemistry*
  • Plant Extracts / therapeutic use
  • Soybeans / chemistry*
  • Time Factors


  • Plant Extracts