I used to play tennis and my knees started to hurt. An old timer told me to try cod liver oil. I didn't believe him and a physical therapist friend asked if it Lubed the Joints. It may. One cap would relieve the pain in 15min, and it wouldn't come back till I stressed my knees, twisting while carrying something heavy, usually a few weeks.
I often wondered what the cod did. I read a NE Journal of Med newsletter around the time and they were doing a study on arthritis and giving Fish Oil Caps. 20/day, and geting 30% improvement. I thought to myself. Use Cod!!) Years later i saw a forensic show about a woman who was shot in the knee. Because of the location they left the bullet in. Weeks later she died of Lead Poisoning. They said, the Synovial fluid that Lubes the joints displved the bullet. I looked up the fluid and it has Vit A in it. Cod is A & D.
I had a dog who I believe had a heat stroke. He couldn't back up without falling. It was a Sunday nite so I gave him a cod cap And some Ephedrine, since i knew that could strengthen muscles. I only gave one of each and he was at least stable for 2 yrs till he died at 14.
I have had different knee pains since and the cod didn't help. I tried glucosamine and That Didn't help. I heard about MSM and tried that. The first brand, Nature's Bounty, cured a chronic sinus problem I had, but Not my knee pain, I figured I would need more so picked up my fav brand at the time, Sundown, and that cured a muscle pain problem I got from a chemical exposure injury. Still having the knee pains I bought every brand of MSM I found. The 3rd one, Natrol took my knee pain away in an hr. I didn't realize the glucosamine was needed with it since I had stoped it the day before. 4mo later when the pain came back, the MSM didn't help. I remembered I had stoped the Glucos. so took it. An hr later the pain left. I have had to take them after 6, 10, 16, 18 mo, and recently 2 yrs between pains. I added Hyaluronic acid since the last time with lifting weights, I was geting a Different twinge, and Something cured it... for now. Not sure what I have since each problem the Different things cured has been Different. A friend who Had surgery insisted that I Needed it. Not when I can find a cure...
Whether pets or humans, The last thing I would take or give are drugs, and the Very Very last would be surgery.