Dasuquin with MSM Soft Chews for Large Dogs is a premium joint health supplement that contains the combination of glucosamine hydrochloride, chondroitin sulfate and avocado/soybean unsaponifiables (ASU) to help support your pet’s joints. Each soft chew also contains methylsulfonylmethane (MSM), a source of sulfur, which helps support joint health. Dasuquin joint health supplements are brought to you by Nutramax Laboratories Veterinary Sciences, the #1 veterinarian recommended supplement company. ?Source: Among veterinary brands. Survey conducted among small animal veterinarians who recommended oral joint health supplements. *Source: Survey conducted among small animal veterinarians who recommended animal supplements.