I have always used the Omega Alpha products on my performance horses, some of my favourites being the Biotic 8, and Stasis. Recently my sister won a prize basket full of Omega Alpha products for dogs and in the basket was a bottle of Pet Vitality - Senior Formula. I have a 10-year-old Blue Heeler/ Border Collie that has struggled with some hip mobility issues over the past 2 years. I've tried recommendations from my Vet and other over-the-counter products that didn't make a huge difference (especially after a day of hiking or hard playing) Tuff has been on the Pet Vitality formula for just over a month and I am blown away with how well it has worked. He is able to play fetch for hours again without getting sore (typical heeler) he's more comfortable on long truck rides and I feel like I don't have to worry about him being able to stand up by himself at the end of a long day. I am so grateful to have my little traveling companion back to his normal self and I hope we can enjoy many more adventures over the coming years. Thank you Omega Alpha for formulating such incredible products that actually work. Taylor, Tuff and the "Herd"