I used to give my bitch SA37, but can't seem to get hold of it half the time. So having read on the Dorwest website about the "37 minerals" in Kelp, the penny dropped.... ....and I bought some Keepers Mix, which is powdered kelp, plus other stuff..
Early days yet, but her coat looks at least as good, in fact maybe a bit better already, on Keepers Mix as opposed to the other stuff, and she definitely eats it much better, she used to be a bit sniffy about the other powder on her food.
Anyway I'd sooner support a British family business than a multi national pharmacist........
Y